Re: [MBZ] Hard start problem returns- Update
That is a possibility that I didn't want to contemplate. It's in the bottom of the valley and not a fun job to get to. It does have a bit more then the usually heard about 100,000 miles on the pump. I guess I may have to ask about that the next time I go to Jacksonville. Manfred Date: Sun, 20 Jun 2010 17:59:39 -0500 (GMT-05:00) From: Peter Frederick psf...@earthlink.net Subject: Re: [MBZ] Hard start problem returns- Update Message-ID: Check with a diesel injection service -- I'm not familiar with this particular pump, but a failed pressure valve or a worn rotor will give this problem, along with low power warm. You should NOT be able to get vapor lock, as the injection lines should be holding pressure up to the pop pressure of the injectors! 1500 psi is typical, now way the fuel can get hot enough to boil unless the pressure isn't holding in the lines. Might be time for a pump overhaul, those distributor pumps often require lubrication supplement with ultra low sulfur fuel or they wear fast. My old Volvo pump had to be rebuilt for this reason. Peter ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Hard start problem returns- Update
The injection pump is a distributor type pump, the same one that is used on the 6.2 just turned up a bit. It doesn't have any air leaks. There is a small valve on top of the final filter that never has any air under it unless I have just changed the filters. The supply pump is an electric unit that I installed right next to the tank so the whole supply line except two connections and about 6 of hose is under pressure. The pump starts when the key is turned and you can hear the tone change when the pressure in the system is up to the limit that the pump can push which is about 7-8 lbs. That is the same amount as the original engine mounted pump did. I replaced it to make bleeding the filters easier after replacement and because the engine mounted pump has a habit of leaking fuel into the oil when the diaphragm goes bad. A bit of oil smoke after starting cold but it still starts right when you turn the key after the glow plugs cycle. No turning over to speak of just turn to start and it starts right now. The only thing that matches the problem is a vapor lock problem. It changes with the fuel supply and outside temp and if you have ever seen a big block in a van then you know about the clearance and heat issues in the engine compartment. The 6.5 is the same size as a big block. The other thing is that I remember it as starting back when they started with this super low sulfur fuel. Manfred Date: Sat, 19 Jun 2010 20:04:29 -0500 From: Peter Frederick psf...@earthlink.net Subject: Re: [MBZ] Hard start problem returns- Update Mid to late 70's Chevy V8s were terrible about roasting starters. As noted, this won't be the case if you have vapor lock in the injection lines. I'd lean toward a leak on the suction side of the fuel system. I'm not familiar with that particular engine, does it have a distributor type pump or an in-line? If it has unit injectors, you definitely have an air leak or a bad supply pump. I doubt it could be a compression problem, as that would give you fits starting cold, not hot, and would produce copious white smoke as you cranked and it did not start. No smoke, it's a fuel supply issue somewhere. Peter ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Hard start problem returns- Update
Check with a diesel injection service -- I'm not familiar with this particular pump, but a failed pressure valve or a worn rotor will give this problem, along with low power warm. You should NOT be able to get vapor lock, as the injection lines should be holding pressure up to the pop pressure of the injectors! 1500 psi is typical, now way the fuel can get hot enough to boil unless the pressure isn't holding in the lines. Might be time for a pump overhaul, those distributor pumps often require lubrication supplement with ultra low sulfur fuel or they wear fast. My old Volvo pump had to be rebuilt for this reason. Peter -Original Message- From: MG trainpain2...@yahoo.com Sent: Jun 20, 2010 5:20 PM To: Mercedes Discussion List mercedes@okiebenz.com Subject: Re: [MBZ] Hard start problem returns- Update The injection pump is a distributor type pump, the same one that is used on the 6.2 just turned up a bit. It doesn't have any air leaks. There is a small valve on top of the final filter that never has any air under it unless I have just changed the filters. The supply pump is an electric unit that I installed right next to the tank so the whole supply line except two connections and about 6 of hose is under pressure. The pump starts when the key is turned and you can hear the tone change when the pressure in the system is up to the limit that the pump can push which is about 7-8 lbs. That is the same amount as the original engine mounted pump did. I replaced it to make bleeding the filters easier after replacement and because the engine mounted pump has a habit of leaking fuel into the oil when the diaphragm goes bad. A bit of oil smoke after starting cold but it still starts right when you turn the key after the glow plugs cycle. No turning over to speak of just turn to start and it starts right now. The only thing that matches the problem is a vapor lock problem. It changes with the fuel supply and outside temp and if you have ever seen a big block in a van then you know about the clearance and heat issues in the engine compartment. The 6.5 is the same size as a big block. The other thing is that I remember it as starting back when they started with this super low sulfur fuel. Manfred Date: Sat, 19 Jun 2010 20:04:29 -0500 From: Peter Frederick psf...@earthlink.net Subject: Re: [MBZ] Hard start problem returns- Update Mid to late 70's Chevy V8s were terrible about roasting starters. As noted, this won't be the case if you have vapor lock in the injection lines. I'd lean toward a leak on the suction side of the fuel system. I'm not familiar with that particular engine, does it have a distributor type pump or an in-line? If it has unit injectors, you definitely have an air leak or a bad supply pump. I doubt it could be a compression problem, as that would give you fits starting cold, not hot, and would produce copious white smoke as you cranked and it did not start. No smoke, it's a fuel supply issue somewhere. Peter ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Hard start problem returns- Update
Peter, It took me a while to get to this due to computer problems. I guess this was meant for me with the mention of the Chevy. The van has a new starter. I replaced it and installed the heat shield that was missing as I also thought that might be one of the problems. To some extent the starter helped with starting in general as the new one turns the engine over a lot faster. Still doesn't change the hot start after the engine has been off for about 15 to 20 min. Before that its fine though you do notice that it takes longer to start the longer it sits, heat soaking. After about 2-3 hours it's fine again. No increase in the oil level or thinning of the oil. Still it also changes with the almost every fill up. With one tank of fuel it may do it and the next it won't. I try to stay away from Shell as that seems to be one that has done it more often then others. There have been other no name stations that have also had fuel with the same problem. All that said I think that compression may be part of the problem as it is a rather high mileage engine for a 6.5. It has over 200,000 miles on it and people that I have talked to around here seem to think that is more then I can expect from one of those. Anyway I only use it now and then when I have to pull a heavy trailer. Lately it has been the 'small' 1/2 ton military trailer usually with about 3000lbs of sand on it. :-) The 300D doesn't seem to be able to manage that quite as well and the hitch on it is a bit too low anyway. In any case I'm too lazy to do a compression check on the engine as I am getting to the point where the contortions needed to do that are just too much just to find out if that's the problem. I'll just keep going with it till it dies and then get rid of it. Manfred Date: Wed, 16 Jun 2010 22:12:51 -0500 From: Peter Frederick psf...@earthlink.net Subject: Re: [MBZ] Hard start problem returns- Update You should also check the current draw on the starter when hot. When the windings go bad, they get high resistance, and that excess resistance goes way up with temperature, so when you crank with a bad starter that is already hot, it won't turn the engine fast enough to start. 100 rpm minimum, anything less and the compression leaks down too low for it to fire even with glow plugs. Worth a check, as this condition will give you the same problems (although it won't respond to bleeding the lines). GM was famous for roasted starters, especially Chevy, since the starter was less than an inch from the exhaust manifold! It's also possible that you have an internal leak in the IP -- you aren't making oil are you? check for fuel in the oil, of present time to fined a used IP. Peter ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Hard start problem returns- Update
Mid to late 70's Chevy V8s were terrible about roasting starters. As noted, this won't be the case if you have vapor lock in the injection lines. I'd lean toward a leak on the suction side of the fuel system. I'm not familiar with that particular engine, does it have a distributor type pump or an in-line? If it has unit injectors, you definitely have an air leak or a bad supply pump. I doubt it could be a compression problem, as that would give you fits starting cold, not hot, and would produce copious white smoke as you cranked and it did not start. No smoke, it's a fuel supply issue somewhere. Peter ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Hard start problem returns- Update
I don't know of a mechanism that would cause the system to lose prime when hot but then regain prime after it cooled off. That's not to say that it doesn't exist, but I'd love to hear how that works. Let me restate your problem to make sure I understand. 123 turbo diesel - OM617.952 engine. Cold engine - fires right up with no priming and 'normal' cranking. Hot engine - no start unless you operate the priming pump. Once running there are no other symptoms (power is fine, mileage is normal, idle is smooth). History of the problem - it has existed for years. Seasonal influence - problem is worse in warm months. Have I got it right? -Max -Original Message- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Mike Esh Sent: Wednesday, June 16, 2010 7:20 PM To: Mercedes Discussion List Subject: Re: [MBZ] Hard start problem returns- Update Steel pipes and car are very good condition with minimal rust. I checked all connections on filter assembly and made sure all fittings had both washers. O-rings are new on the bolt for the filter. There are two of them, the lower one is smaller than the upper one. I hear nothing when operating pump manually. Could this be allowing fuel to return when the engine is hot and correct itself as the engine cools? No rising oil, I usually add a quart between changes. Thanks for the input, Mike On Jun 16, 2010, at 6:26 PM, Dieselhead wrote: Assuming that all the steel pipes are not rusted. .. Some fuel filters have o-rings on the bolt that holds the filter in place, older ones have an aluminum seal under the head of the bolt. I think yours has orings. Maybe someone else can say for sure. Air can leak in at these orings. Any loose banjo fitting at the filter can leak. The banjo fittings into the IP and out of the IP can leak. All banjo fittings are supposed to have an aluminum ring under the bolt head and under the fitting. Absence of any aluminum seal ring can allow air in the lines. There is a check valve on the backside of the IP at the exit line banjo fitting. It is possible somebody removed this. When it is very quiet, you can hear the check valve operating when you pump the hand primer pump. Do you have a rising oil level? It is possible, but very rare, for the IP shaft to leak fuel into the crankcase. I checked/replaced all connections and hoses and cannot determine where anything is leaking. Everything is dry and clean. I can actually see the fuel level in the clear filter level drop. I appears to be draining toward the spin on filter. Is there check valve somewhere that is allowing the fuel to drain back when it is hot. Is the injection pump going bad? I am getting so frustrated. Anyone within 200 miles of Whitehall, MI that has knowledge of how to fix the issue? I would be willing to travel to solve this. Thanks, Mike On Jun 11, 2010, at 3:21 PM, John Reames wrote: Check to see if your vent line is plugged... Either fighting to pull the filler cap or hearing air go in. I had an 84 sd that was taking on air until I blew out the vent line... -- John W Reames jwrea...@comcast.net Home: +14106646986 Mobile: +14437915905 On Jun 11, 2010, at 14:05, Dieselhead 126die...@gmail.com wrote: A stream of bubbles in the clear filter only indicates an air leak in the suction line. An air leak after the clear filter, in lines, transfer pump, filter, IP, or return lines do not indicate by bubbles in the clear filter. You can use the presence or absence of bubbles to focus your efforts before, or after the prefilter. If the hoses are old, OFTEN, there are multiple air leaks. If the hoses are all less than 2-3 years old, it is likely to be a clamp that is not tight. It is a good idea to change all the fuel hoses every 5 years or so. (yes the original hoses lasted 10-20 years.) I have not had MB replacements last that long. FLAPS hose is usually good for 5 years. I only use OE or OEM radiator hoses. They are still noticeably better than any third party hoses. Also note that the hand priming pump only moves fuel into the injection pump, NOT out the injection lines to the injectors. You operate the priming pump about 50 to 70 times to prime the injection pump; you will know that it is primed when the noise changes and the pump action firms up. How does the car run once you get it started? Can you reach top speed or does it lose power at highway speeds? Watch the clear in- line filter - is there a stream of bubbles entering? -Max -Original Message- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Dieselhead Sent: Friday, June 11, 2010 12:58 PM To: Mercedes Discussion List Subject: Re: [MBZ] Hard start problem returns Try bleeding the fuel system at the filter (Top bolt, or line out) while you pump the primer. It sounds like air is getting
Re: [MBZ] Hard start problem returns- Update
Yes that is correct only the problem started about a year ago. Who is still looking for rusty lines and leaks in the system. Mike On Jun 17, 2010, at 6:39 AM, Dillon, Meade M CIV SPAWARSYSCEN- ATLANTIC, 53310 wrote: I don't know of a mechanism that would cause the system to lose prime when hot but then regain prime after it cooled off. That's not to say that it doesn't exist, but I'd love to hear how that works. Let me restate your problem to make sure I understand. 123 turbo diesel - OM617.952 engine. Cold engine - fires right up with no priming and 'normal' cranking. Hot engine - no start unless you operate the priming pump. Once running there are no other symptoms (power is fine, mileage is normal, idle is smooth). History of the problem - it has existed for years. Seasonal influence - problem is worse in warm months. Have I got it right? -Max -Original Message- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Mike Esh Sent: Wednesday, June 16, 2010 7:20 PM To: Mercedes Discussion List Subject: Re: [MBZ] Hard start problem returns- Update Steel pipes and car are very good condition with minimal rust. I checked all connections on filter assembly and made sure all fittings had both washers. O-rings are new on the bolt for the filter. There are two of them, the lower one is smaller than the upper one. I hear nothing when operating pump manually. Could this be allowing fuel to return when the engine is hot and correct itself as the engine cools? No rising oil, I usually add a quart between changes. Thanks for the input, Mike On Jun 16, 2010, at 6:26 PM, Dieselhead wrote: Assuming that all the steel pipes are not rusted. .. Some fuel filters have o-rings on the bolt that holds the filter in place, older ones have an aluminum seal under the head of the bolt. I think yours has orings. Maybe someone else can say for sure. Air can leak in at these orings. Any loose banjo fitting at the filter can leak. The banjo fittings into the IP and out of the IP can leak. All banjo fittings are supposed to have an aluminum ring under the bolt head and under the fitting. Absence of any aluminum seal ring can allow air in the lines. There is a check valve on the backside of the IP at the exit line banjo fitting. It is possible somebody removed this. When it is very quiet, you can hear the check valve operating when you pump the hand primer pump. Do you have a rising oil level? It is possible, but very rare, for the IP shaft to leak fuel into the crankcase. I checked/replaced all connections and hoses and cannot determine where anything is leaking. Everything is dry and clean. I can actually see the fuel level in the clear filter level drop. I appears to be draining toward the spin on filter. Is there check valve somewhere that is allowing the fuel to drain back when it is hot. Is the injection pump going bad? I am getting so frustrated. Anyone within 200 miles of Whitehall, MI that has knowledge of how to fix the issue? I would be willing to travel to solve this. Thanks, Mike On Jun 11, 2010, at 3:21 PM, John Reames wrote: Check to see if your vent line is plugged... Either fighting to pull the filler cap or hearing air go in. I had an 84 sd that was taking on air until I blew out the vent line... -- John W Reames jwrea...@comcast.net Home: +14106646986 Mobile: +14437915905 On Jun 11, 2010, at 14:05, Dieselhead 126die...@gmail.com wrote: A stream of bubbles in the clear filter only indicates an air leak in the suction line. An air leak after the clear filter, in lines, transfer pump, filter, IP, or return lines do not indicate by bubbles in the clear filter. You can use the presence or absence of bubbles to focus your efforts before, or after the prefilter. If the hoses are old, OFTEN, there are multiple air leaks. If the hoses are all less than 2-3 years old, it is likely to be a clamp that is not tight. It is a good idea to change all the fuel hoses every 5 years or so. (yes the original hoses lasted 10-20 years.) I have not had MB replacements last that long. FLAPS hose is usually good for 5 years. I only use OE or OEM radiator hoses. They are still noticeably better than any third party hoses. Also note that the hand priming pump only moves fuel into the injection pump, NOT out the injection lines to the injectors. You operate the priming pump about 50 to 70 times to prime the injection pump; you will know that it is primed when the noise changes and the pump action firms up. How does the car run once you get it started? Can you reach top speed or does it lose power at highway speeds? Watch the clear in- line filter - is there a stream of bubbles entering? -Max -Original Message- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Dieselhead Sent: Friday, June 11, 2010 12:58 PM To: Mercedes Discussion
Re: [MBZ] Hard start problem returns- Update
I think the idea of the checkvalve failing and allowing it to leak down is worth pursuing, although I don't see how it would fix itself when cold. Maybe run a can if Diesel Purge to clean off the seat of said check valve? -Max -Original Message- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Mike Esh Sent: Thursday, June 17, 2010 9:02 AM To: Mercedes Discussion List Subject: Re: [MBZ] Hard start problem returns- Update Yes that is correct only the problem started about a year ago. Who is still looking for rusty lines and leaks in the system. Mike On Jun 17, 2010, at 6:39 AM, Dillon, Meade M CIV SPAWARSYSCEN- ATLANTIC, 53310 wrote: I don't know of a mechanism that would cause the system to lose prime when hot but then regain prime after it cooled off. That's not to say that it doesn't exist, but I'd love to hear how that works. Let me restate your problem to make sure I understand. 123 turbo diesel - OM617.952 engine. Cold engine - fires right up with no priming and 'normal' cranking. Hot engine - no start unless you operate the priming pump. Once running there are no other symptoms (power is fine, mileage is normal, idle is smooth). History of the problem - it has existed for years. Seasonal influence - problem is worse in warm months. Have I got it right? -Max -Original Message- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Mike Esh Sent: Wednesday, June 16, 2010 7:20 PM To: Mercedes Discussion List Subject: Re: [MBZ] Hard start problem returns- Update Steel pipes and car are very good condition with minimal rust. I checked all connections on filter assembly and made sure all fittings had both washers. O-rings are new on the bolt for the filter. There are two of them, the lower one is smaller than the upper one. I hear nothing when operating pump manually. Could this be allowing fuel to return when the engine is hot and correct itself as the engine cools? No rising oil, I usually add a quart between changes. Thanks for the input, Mike On Jun 16, 2010, at 6:26 PM, Dieselhead wrote: Assuming that all the steel pipes are not rusted. .. Some fuel filters have o-rings on the bolt that holds the filter in place, older ones have an aluminum seal under the head of the bolt. I think yours has orings. Maybe someone else can say for sure. Air can leak in at these orings. Any loose banjo fitting at the filter can leak. The banjo fittings into the IP and out of the IP can leak. All banjo fittings are supposed to have an aluminum ring under the bolt head and under the fitting. Absence of any aluminum seal ring can allow air in the lines. There is a check valve on the backside of the IP at the exit line banjo fitting. It is possible somebody removed this. When it is very quiet, you can hear the check valve operating when you pump the hand primer pump. Do you have a rising oil level? It is possible, but very rare, for the IP shaft to leak fuel into the crankcase. I checked/replaced all connections and hoses and cannot determine where anything is leaking. Everything is dry and clean. I can actually see the fuel level in the clear filter level drop. I appears to be draining toward the spin on filter. Is there check valve somewhere that is allowing the fuel to drain back when it is hot. Is the injection pump going bad? I am getting so frustrated. Anyone within 200 miles of Whitehall, MI that has knowledge of how to fix the issue? I would be willing to travel to solve this. Thanks, Mike On Jun 11, 2010, at 3:21 PM, John Reames wrote: Check to see if your vent line is plugged... Either fighting to pull the filler cap or hearing air go in. I had an 84 sd that was taking on air until I blew out the vent line... -- John W Reames jwrea...@comcast.net Home: +14106646986 Mobile: +14437915905 On Jun 11, 2010, at 14:05, Dieselhead 126die...@gmail.com wrote: A stream of bubbles in the clear filter only indicates an air leak in the suction line. An air leak after the clear filter, in lines, transfer pump, filter, IP, or return lines do not indicate by bubbles in the clear filter. You can use the presence or absence of bubbles to focus your efforts before, or after the prefilter. If the hoses are old, OFTEN, there are multiple air leaks. If the hoses are all less than 2-3 years old, it is likely to be a clamp that is not tight. It is a good idea to change all the fuel hoses every 5 years or so. (yes the original hoses lasted 10-20 years.) I have not had MB replacements last that long. FLAPS hose is usually good for 5 years. I only use OE or OEM radiator hoses. They are still noticeably better than any third party hoses. Also note that the hand priming pump only moves fuel into the injection pump, NOT out the injection lines
Re: [MBZ] Hard start problem returns- Update
I checked/replaced all connections and hoses and cannot determine where anything is leaking. Everything is dry and clean. I can actually see the fuel level in the clear filter level drop. I appears to be draining toward the spin on filter. Is there check valve somewhere that is allowing the fuel to drain back when it is hot. Is the injection pump going bad? I am getting so frustrated. Anyone within 200 miles of Whitehall, MI that has knowledge of how to fix the issue? I would be willing to travel to solve this. Thanks, Mike On Jun 11, 2010, at 3:21 PM, John Reames wrote: Check to see if your vent line is plugged... Either fighting to pull the filler cap or hearing air go in. I had an 84 sd that was taking on air until I blew out the vent line... -- John W Reames jwrea...@comcast.net Home: +14106646986 Mobile: +14437915905 On Jun 11, 2010, at 14:05, Dieselhead 126die...@gmail.com wrote: A stream of bubbles in the clear filter only indicates an air leak in the suction line. An air leak after the clear filter, in lines, transfer pump, filter, IP, or return lines do not indicate by bubbles in the clear filter. You can use the presence or absence of bubbles to focus your efforts before, or after the prefilter. If the hoses are old, OFTEN, there are multiple air leaks. If the hoses are all less than 2-3 years old, it is likely to be a clamp that is not tight. It is a good idea to change all the fuel hoses every 5 years or so. (yes the original hoses lasted 10-20 years.) I have not had MB replacements last that long. FLAPS hose is usually good for 5 years. I only use OE or OEM radiator hoses. They are still noticeably better than any third party hoses. Also note that the hand priming pump only moves fuel into the injection pump, NOT out the injection lines to the injectors. You operate the priming pump about 50 to 70 times to prime the injection pump; you will know that it is primed when the noise changes and the pump action firms up. How does the car run once you get it started? Can you reach top speed or does it lose power at highway speeds? Watch the clear in-line filter - is there a stream of bubbles entering? -Max -Original Message- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Dieselhead Sent: Friday, June 11, 2010 12:58 PM To: Mercedes Discussion List Subject: Re: [MBZ] Hard start problem returns Try bleeding the fuel system at the filter (Top bolt, or line out) while you pump the primer. It sounds like air is getting into the fuel system somewhere. A leak at the filter can cause a leak. Bad copper seals in the delivery valves can cause problems. ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Hard start problem returns- Update
Assuming that all the steel pipes are not rusted. .. Some fuel filters have o-rings on the bolt that holds the filter in place, older ones have an aluminum seal under the head of the bolt. I think yours has orings. Maybe someone else can say for sure. Air can leak in at these orings. Any loose banjo fitting at the filter can leak. The banjo fittings into the IP and out of the IP can leak. All banjo fittings are supposed to have an aluminum ring under the bolt head and under the fitting. Absence of any aluminum seal ring can allow air in the lines. There is a check valve on the backside of the IP at the exit line banjo fitting. It is possible somebody removed this. When it is very quiet, you can hear the check valve operating when you pump the hand primer pump. Do you have a rising oil level? It is possible, but very rare, for the IP shaft to leak fuel into the crankcase. I checked/replaced all connections and hoses and cannot determine where anything is leaking. Everything is dry and clean. I can actually see the fuel level in the clear filter level drop. I appears to be draining toward the spin on filter. Is there check valve somewhere that is allowing the fuel to drain back when it is hot. Is the injection pump going bad? I am getting so frustrated. Anyone within 200 miles of Whitehall, MI that has knowledge of how to fix the issue? I would be willing to travel to solve this. Thanks, Mike On Jun 11, 2010, at 3:21 PM, John Reames wrote: Check to see if your vent line is plugged... Either fighting to pull the filler cap or hearing air go in. I had an 84 sd that was taking on air until I blew out the vent line... -- John W Reames jwrea...@comcast.net Home: +14106646986 Mobile: +14437915905 On Jun 11, 2010, at 14:05, Dieselhead 126die...@gmail.com wrote: A stream of bubbles in the clear filter only indicates an air leak in the suction line. An air leak after the clear filter, in lines, transfer pump, filter, IP, or return lines do not indicate by bubbles in the clear filter. You can use the presence or absence of bubbles to focus your efforts before, or after the prefilter. If the hoses are old, OFTEN, there are multiple air leaks. If the hoses are all less than 2-3 years old, it is likely to be a clamp that is not tight. It is a good idea to change all the fuel hoses every 5 years or so. (yes the original hoses lasted 10-20 years.) I have not had MB replacements last that long. FLAPS hose is usually good for 5 years. I only use OE or OEM radiator hoses. They are still noticeably better than any third party hoses. Also note that the hand priming pump only moves fuel into the injection pump, NOT out the injection lines to the injectors. You operate the priming pump about 50 to 70 times to prime the injection pump; you will know that it is primed when the noise changes and the pump action firms up. How does the car run once you get it started? Can you reach top speed or does it lose power at highway speeds? Watch the clear in-line filter - is there a stream of bubbles entering? -Max -Original Message- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Dieselhead Sent: Friday, June 11, 2010 12:58 PM To: Mercedes Discussion List Subject: Re: [MBZ] Hard start problem returns Try bleeding the fuel system at the filter (Top bolt, or line out) while you pump the primer. It sounds like air is getting into the fuel system somewhere. A leak at the filter can cause a leak. Bad copper seals in the delivery valves can cause problems. ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Hard start problem returns- Update
Steel pipes and car are very good condition with minimal rust. I checked all connections on filter assembly and made sure all fittings had both washers. O-rings are new on the bolt for the filter. There are two of them, the lower one is smaller than the upper one. I hear nothing when operating pump manually. Could this be allowing fuel to return when the engine is hot and correct itself as the engine cools? No rising oil, I usually add a quart between changes. Thanks for the input, Mike On Jun 16, 2010, at 6:26 PM, Dieselhead wrote: Assuming that all the steel pipes are not rusted. .. Some fuel filters have o-rings on the bolt that holds the filter in place, older ones have an aluminum seal under the head of the bolt. I think yours has orings. Maybe someone else can say for sure. Air can leak in at these orings. Any loose banjo fitting at the filter can leak. The banjo fittings into the IP and out of the IP can leak. All banjo fittings are supposed to have an aluminum ring under the bolt head and under the fitting. Absence of any aluminum seal ring can allow air in the lines. There is a check valve on the backside of the IP at the exit line banjo fitting. It is possible somebody removed this. When it is very quiet, you can hear the check valve operating when you pump the hand primer pump. Do you have a rising oil level? It is possible, but very rare, for the IP shaft to leak fuel into the crankcase. I checked/replaced all connections and hoses and cannot determine where anything is leaking. Everything is dry and clean. I can actually see the fuel level in the clear filter level drop. I appears to be draining toward the spin on filter. Is there check valve somewhere that is allowing the fuel to drain back when it is hot. Is the injection pump going bad? I am getting so frustrated. Anyone within 200 miles of Whitehall, MI that has knowledge of how to fix the issue? I would be willing to travel to solve this. Thanks, Mike On Jun 11, 2010, at 3:21 PM, John Reames wrote: Check to see if your vent line is plugged... Either fighting to pull the filler cap or hearing air go in. I had an 84 sd that was taking on air until I blew out the vent line... -- John W Reames jwrea...@comcast.net Home: +14106646986 Mobile: +14437915905 On Jun 11, 2010, at 14:05, Dieselhead 126die...@gmail.com wrote: A stream of bubbles in the clear filter only indicates an air leak in the suction line. An air leak after the clear filter, in lines, transfer pump, filter, IP, or return lines do not indicate by bubbles in the clear filter. You can use the presence or absence of bubbles to focus your efforts before, or after the prefilter. If the hoses are old, OFTEN, there are multiple air leaks. If the hoses are all less than 2-3 years old, it is likely to be a clamp that is not tight. It is a good idea to change all the fuel hoses every 5 years or so. (yes the original hoses lasted 10-20 years.) I have not had MB replacements last that long. FLAPS hose is usually good for 5 years. I only use OE or OEM radiator hoses. They are still noticeably better than any third party hoses. Also note that the hand priming pump only moves fuel into the injection pump, NOT out the injection lines to the injectors. You operate the priming pump about 50 to 70 times to prime the injection pump; you will know that it is primed when the noise changes and the pump action firms up. How does the car run once you get it started? Can you reach top speed or does it lose power at highway speeds? Watch the clear in- line filter - is there a stream of bubbles entering? -Max -Original Message- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Dieselhead Sent: Friday, June 11, 2010 12:58 PM To: Mercedes Discussion List Subject: Re: [MBZ] Hard start problem returns Try bleeding the fuel system at the filter (Top bolt, or line out) while you pump the primer. It sounds like air is getting into the fuel system somewhere. A leak at the filter can cause a leak. Bad copper seals in the delivery valves can cause problems. ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to:
Re: [MBZ] Hard start problem returns- Update
One 115 chassis 300D I bought a long time ago was sold with a dis-assembled engine because it was hard to start. I transferred the factory re-man engine I had in a rusting out car to it, and surprise - it was suddenly hard to start! I found a small place where the steel fuel line had been rubbing against the frame. I had rubbed a pin hole through the line. I never saw a leak, it was not wet, but was enough to make the car very hard to start after it sat overnight. I cut he section and inserted a few inches of fuel hose, and the problem was solved. I don't know if this can be related to your issue or not, but I'd check every inch of the feed fuel line. On Wed, Jun 16, 2010 at 6:20 PM, Mike Esh michael...@me.com wrote: Steel pipes and car are very good condition with minimal rust. -- OK Don Panic! (the national past time). ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Hard start problem returns- Update
Well stated. I had the same experience with a small rust spot under a clamp. Not wet. Not much rust. but the car started fine after I cut it out. Michaels's observation that the fuel seems to flow to the filter as the air leaks in indicates the return line. One 115 chassis 300D I bought a long time ago was sold with a dis-assembled engine because it was hard to start. I transferred the factory re-man engine I had in a rusting out car to it, and surprise - it was suddenly hard to start! I found a small place where the steel fuel line had been rubbing against the frame. I had rubbed a pin hole through the line. I never saw a leak, it was not wet, but was enough to make the car very hard to start after it sat overnight. I cut he section and inserted a few inches of fuel hose, and the problem was solved. I don't know if this can be related to your issue or not, but I'd check every inch of the feed fuel line. On Wed, Jun 16, 2010 at 6:20 PM, Mike Esh michael...@me.com wrote: Steel pipes and car are very good condition with minimal rust. -- OK Don Panic! (the national past time). ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Hard start problem returns- Update
You should also check the current draw on the starter when hot. When the windings go bad, they get high resistance, and that excess resistance goes way up with temperature, so when you crank with a bad starter that is already hot, it won't turn the engine fast enough to start. 100 rpm minimum, anything less and the compression leaks down too low for it to fire even with glow plugs. Worth a check, as this condition will give you the same problems (although it won't respond to bleeding the lines). GM was famous for roasted starters, especially Chevy, since the starter was less than an inch from the exhaust manifold! It's also possible that you have an internal leak in the IP -- you aren't making oil are you? check for fuel in the oil, of present time to fined a used IP. Peter ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
