Re: Stus-List Yamaha 4hp 2 cycle
Josh I took a picture of the carb. Thats my cell below. I can send it to you to discuss however, I think I know where it is. FYI. Carb cleaned, fuel lines tank pickup all replaced. Thanks in advance. David F. Risch (401) 419-4650 From: CnC-List On Behalf Of Josh Muckley via CnC-List Sent: Wednesday, June 10, 2020 11:53 AM To: C List Cc: Josh Muckley Subject: Re: Stus-List Yamaha 4hp 2 cycle Year and serial number would probably help. On Wed, Jun 10, 2020, 11:45 David Risch via CnC-List mailto:cnc-list@cnc-list.com>> wrote: Thanks Josh Yamaha 4hp 2 cycle. I can get serial number if you need more info… David F. Risch (401) 419-4650 From: CnC-List mailto:cnc-list-boun...@cnc-list.com>> On Behalf Of Josh Muckley via CnC-List Sent: Wednesday, June 10, 2020 10:36 AM To: C List mailto:cnc-list@cnc-list.com>> Cc: Josh Muckley mailto:muckl...@gmail.com>> Subject: Re: Stus-List Yamaha 4hp 2 cycle David, There has to be an orifice (jet) or screw. Are you sure a screw isn't hidden under a plastic cowl? Get me an exact make and model so I can do some research. Josh On Wed, Jun 10, 2020, 08:08 David Risch via CnC-List mailto:cnc-list@cnc-list.com>> wrote: Josh and Chuck, Mixture is new with AV gas so no issues there. Only one adjustment screw on carb. Seems to only affect low throttle. As said all good in neutral and good up until ¾ throttle in gear. Chuck mentioned if spark plug grey and chalky, which it is, it is running lean at top end. How does one adjust top end without adjustment screw. Thanks in advance. David F. Risch (401) 419-4650 From: CnC-List mailto:cnc-list-boun...@cnc-list.com>> On Behalf Of Josh Muckley via CnC-List Sent: Sunday, June 7, 2020 10:17 AM To: C List mailto:cnc-list@cnc-list.com>> Cc: Josh Muckley mailto:muckl...@gmail.com>> Subject: Re: Stus-List Yamaha 4hp 2 cycle Follow my carb tuning video. Post back with questions. https://youtu.be/caIdvC8WGDg Sounds like the idle/throttle screw (T) is keeping the butterfly open too far with no throttle applied. It just so happens that in gear there is enough load to slow 'er down. At full throttle is sounds like probably too much fuel (H). I think that if it was too little it would die. Since both of these "symptoms could be a result of too much low throttle fuel (L) you should probably start by dialing it back a bit and see how thing go. By doing this you will lower the fuel at idle AND lower the fuel a full throttle. If you're lucky and my diagnosis is correct then you'll kill too birds with one stone. My advice is based on having 3 adjustment screws H (high throttle), L (low throttle), T (min throttle). If you're missing any one of these then it has a jet which serves in its place. Josh Muckley S/V Sea Hawk 1989 C 37+ Solomons, MD On Sun, Jun 7, 2020, 09:29 David Risch via CnC-List mailto:cnc-list@cnc-list.com>> wrote: So instead of giving it away I rebuilt the carb and half dozen other fixes this winter. Runs and idles great, but at full throttle she bogs down continues to run, but sounds rougher.When out gear it goes right to full throttle. Perhaps overpropped? Sent from my Android. Please forgive typos. Thank you. ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Re: Stus-List Yamaha 4hp 2 cycle
A partially blocked main jet could cause carb to run lean on the top end. Mixture and idle screws don’t adjust anything above the midrange of the power band. A fine wire can be used to clear any debris that could block fuel flow through the jet. Also check the float level. If the float is set too low it could be starving for fuel at higher rpms with full throttle. Chuck > On Jun 10, 2020, at 11:45 AM, David Risch via CnC-List > wrote: > > > Thanks Josh > > Yamaha 4hp 2 cycle. I can get serial number if you need more info… > > David F. Risch > (401) 419-4650 > > From: CnC-List On Behalf Of Josh Muckley via > CnC-List > Sent: Wednesday, June 10, 2020 10:36 AM > To: C List > Cc: Josh Muckley > Subject: Re: Stus-List Yamaha 4hp 2 cycle > > David, > > There has to be an orifice (jet) or screw. Are you sure a screw isn't hidden > under a plastic cowl? > > Get me an exact make and model so I can do some research. > > Josh > > > > On Wed, Jun 10, 2020, 08:08 David Risch via CnC-List > wrote: > Josh and Chuck, > > Mixture is new with AV gas so no issues there. Only one adjustment screw on > carb. Seems to only affect low throttle. As said all good in neutral and > good up until ¾ throttle in gear. Chuck mentioned if spark plug grey and > chalky, which it is, it is running lean at top end. How does one adjust top > end without adjustment screw. > > Thanks in advance. > > David F. Risch > (401) 419-4650 > > From: CnC-List On Behalf Of Josh Muckley via > CnC-List > Sent: Sunday, June 7, 2020 10:17 AM > To: C List > Cc: Josh Muckley > Subject: Re: Stus-List Yamaha 4hp 2 cycle > > Follow my carb tuning video. Post back with questions. > > https://youtu.be/caIdvC8WGDg > > Sounds like the idle/throttle screw (T) is keeping the butterfly open too far > with no throttle applied. It just so happens that in gear there is enough > load to slow 'er down. At full throttle is sounds like probably too much > fuel (H). I think that if it was too little it would die. Since both of > these "symptoms could be a result of too much low throttle fuel (L) you > should probably start by dialing it back a bit and see how thing go. By > doing this you will lower the fuel at idle AND lower the fuel a full > throttle. If you're lucky and my diagnosis is correct then you'll kill too > birds with one stone. > > My advice is based on having 3 adjustment screws H (high throttle), L (low > throttle), T (min throttle). If you're missing any one of these then it has > a jet which serves in its place. > > Josh Muckley > S/V Sea Hawk > 1989 C 37+ > Solomons, MD > > > On Sun, Jun 7, 2020, 09:29 David Risch via CnC-List > wrote: > So instead of giving it away I rebuilt the carb and half dozen other fixes > this winter. > > Runs and idles great, but at full throttle she bogs down continues to run, > but sounds rougher.When out gear it goes right to full throttle. > > Perhaps overpropped? > > Sent from my Android. Please forgive typos. Thank you. > > ___ > > Thanks everyone for supporting this list with your contributions. Each and > every one is greatly appreciated. If you want to support the list - use > PayPal to send contribution -- https://www.paypal.me/stumurray > > ___ > > Thanks everyone for supporting this list with your contributions. Each and > every one is greatly appreciated. If you want to support the list - use > PayPal to send contribution -- https://www.paypal.me/stumurray > > ___ > > Thanks everyone for supporting this list with your contributions. Each and > every one is greatly appreciated. If you want to support the list - use > PayPal to send contribution -- https://www.paypal.me/stumurray > ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Re: Stus-List Yamaha 4hp 2 cycle
I keep a jug of it for my lawnmower. It is amazing how trouble free it is without car gas in it. On the other side of the equation I know someone who decided to use car gas in a seaplane and sure enough it came home one day at the end of a towline. Ethanol defeats the water separators airplanes have – and boats too for that matter ☹ Joe Della Barba Coquina C 35 MK I www.dellabarba.com From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of David Risch via CnC-List Sent: Wednesday, June 10, 2020 11:39 AM To: cnc-list@cnc-list.com Cc: David Risch Subject: [EXTERNAL] Re: Stus-List Yamaha 4hp 2 cycle I use it for the no ethanol component. Hate ethanol… David F. Risch (401) 419-4650 From: CnC-List mailto:cnc-list-boun...@cnc-list.com>> On Behalf Of Della Barba, Joe via CnC-List Sent: Wednesday, June 10, 2020 10:38 AM To: cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com> Cc: Della Barba, Joe mailto:joe.della.ba...@ssa.gov>> Subject: Stus-List Yamaha 4hp 2 cycle Avgas is in 100 octane LL? That will eventually lead foul the spark plug, so you’ll need to check it every so often. On the plus side it doesn’t have stink perfume added to it, so if you spill it on yourself you won’t stink all day. Joe Della Barba Coquina C 35 MK I www.dellabarba.com<https://protect2.fireeye.com/v1/url?k=bda4e16a-e0d7720b-bda4c81d-ac1f6b44e86e-7595699e3fd42846=1=634cda22-0fbd-4e10-8bfc-94fef0baa4a4=http%3A%2F%2Fwww.dellabarba.com%2F> ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Re: Stus-List Yamaha 4hp 2 cycle
Year and serial number would probably help. On Wed, Jun 10, 2020, 11:45 David Risch via CnC-List wrote: > Thanks Josh > > > > Yamaha 4hp 2 cycle. I can get serial number if you need more info… > > > > *David F. Risch* > > *(401) 419-4650* > > > > *From:* CnC-List *On Behalf Of *Josh > Muckley via CnC-List > *Sent:* Wednesday, June 10, 2020 10:36 AM > *To:* C List > *Cc:* Josh Muckley > *Subject:* Re: Stus-List Yamaha 4hp 2 cycle > > > > David, > > > > There has to be an orifice (jet) or screw. Are you sure a screw isn't > hidden under a plastic cowl? > > > > Get me an exact make and model so I can do some research. > > > > Josh > > > > > > > > On Wed, Jun 10, 2020, 08:08 David Risch via CnC-List < > cnc-list@cnc-list.com> wrote: > > Josh and Chuck, > > > > Mixture is new with AV gas so no issues there. Only one adjustment screw > on carb. Seems to only affect low throttle. As said all good in neutral > and good up until ¾ throttle in gear. Chuck mentioned if spark plug grey > and chalky, which it is, it is running lean at top end. How does one > adjust top end without adjustment screw. > > > > Thanks in advance. > > > > *David F. Risch* > > *(401) 419-4650* > > > > *From:* CnC-List *On Behalf Of *Josh > Muckley via CnC-List > *Sent:* Sunday, June 7, 2020 10:17 AM > *To:* C List > *Cc:* Josh Muckley > *Subject:* Re: Stus-List Yamaha 4hp 2 cycle > > > > Follow my carb tuning video. Post back with questions. > > > > https://youtu.be/caIdvC8WGDg > > > > Sounds like the idle/throttle screw (T) is keeping the butterfly open too > far with no throttle applied. It just so happens that in gear there is > enough load to slow 'er down. At full throttle is sounds like probably too > much fuel (H). I think that if it was too little it would die. Since both > of these "symptoms could be a result of too much low throttle fuel (L) you > should probably start by dialing it back a bit and see how thing go. By > doing this you will lower the fuel at idle AND lower the fuel a full > throttle. If you're lucky and my diagnosis is correct then you'll kill too > birds with one stone. > > > > My advice is based on having 3 adjustment screws H (high throttle), L (low > throttle), T (min throttle). If you're missing any one of these then it > has a jet which serves in its place. > > > > Josh Muckley > > S/V Sea Hawk > > 1989 C 37+ > > Solomons, MD > > > > On Sun, Jun 7, 2020, 09:29 David Risch via CnC-List > wrote: > > So instead of giving it away I rebuilt the carb and half dozen other fixes > this winter. > > Runs and idles great, but at full throttle she bogs down continues to run, > but sounds rougher.When out gear it goes right to full throttle. > > Perhaps overpropped? > > Sent from my Android. Please forgive typos. Thank you. > > > > ___ > > Thanks everyone for supporting this list with your contributions. Each > and every one is greatly appreciated. If you want to support the list - > use PayPal to send contribution -- https://www.paypal.me/stumurray > > ___ > > Thanks everyone for supporting this list with your contributions. Each > and every one is greatly appreciated. If you want to support the list - > use PayPal to send contribution -- https://www.paypal.me/stumurray > > ___ > > Thanks everyone for supporting this list with your contributions. Each > and every one is greatly appreciated. If you want to support the list - > use PayPal to send contribution -- https://www.paypal.me/stumurray > > ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Re: Stus-List Yamaha 4hp 2 cycle
Thanks Josh Yamaha 4hp 2 cycle. I can get serial number if you need more info… David F. Risch (401) 419-4650 From: CnC-List On Behalf Of Josh Muckley via CnC-List Sent: Wednesday, June 10, 2020 10:36 AM To: C List Cc: Josh Muckley Subject: Re: Stus-List Yamaha 4hp 2 cycle David, There has to be an orifice (jet) or screw. Are you sure a screw isn't hidden under a plastic cowl? Get me an exact make and model so I can do some research. Josh On Wed, Jun 10, 2020, 08:08 David Risch via CnC-List mailto:cnc-list@cnc-list.com>> wrote: Josh and Chuck, Mixture is new with AV gas so no issues there. Only one adjustment screw on carb. Seems to only affect low throttle. As said all good in neutral and good up until ¾ throttle in gear. Chuck mentioned if spark plug grey and chalky, which it is, it is running lean at top end. How does one adjust top end without adjustment screw. Thanks in advance. David F. Risch (401) 419-4650 From: CnC-List mailto:cnc-list-boun...@cnc-list.com>> On Behalf Of Josh Muckley via CnC-List Sent: Sunday, June 7, 2020 10:17 AM To: C List mailto:cnc-list@cnc-list.com>> Cc: Josh Muckley mailto:muckl...@gmail.com>> Subject: Re: Stus-List Yamaha 4hp 2 cycle Follow my carb tuning video. Post back with questions. https://youtu.be/caIdvC8WGDg Sounds like the idle/throttle screw (T) is keeping the butterfly open too far with no throttle applied. It just so happens that in gear there is enough load to slow 'er down. At full throttle is sounds like probably too much fuel (H). I think that if it was too little it would die. Since both of these "symptoms could be a result of too much low throttle fuel (L) you should probably start by dialing it back a bit and see how thing go. By doing this you will lower the fuel at idle AND lower the fuel a full throttle. If you're lucky and my diagnosis is correct then you'll kill too birds with one stone. My advice is based on having 3 adjustment screws H (high throttle), L (low throttle), T (min throttle). If you're missing any one of these then it has a jet which serves in its place. Josh Muckley S/V Sea Hawk 1989 C 37+ Solomons, MD On Sun, Jun 7, 2020, 09:29 David Risch via CnC-List mailto:cnc-list@cnc-list.com>> wrote: So instead of giving it away I rebuilt the carb and half dozen other fixes this winter. Runs and idles great, but at full throttle she bogs down continues to run, but sounds rougher.When out gear it goes right to full throttle. Perhaps overpropped? Sent from my Android. Please forgive typos. Thank you. ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Re: Stus-List Yamaha 4hp 2 cycle
I use it for the no ethanol component. Hate ethanol… David F. Risch (401) 419-4650 From: CnC-List On Behalf Of Della Barba, Joe via CnC-List Sent: Wednesday, June 10, 2020 10:38 AM To: cnc-list@cnc-list.com Cc: Della Barba, Joe Subject: Stus-List Yamaha 4hp 2 cycle Avgas is in 100 octane LL? That will eventually lead foul the spark plug, so you’ll need to check it every so often. On the plus side it doesn’t have stink perfume added to it, so if you spill it on yourself you won’t stink all day. Joe Della Barba Coquina C 35 MK I www.dellabarba.com<http://www.dellabarba.com> From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Francois Rivard via CnC-List Sent: Wednesday, June 10, 2020 10:20 AM To: David mailto:davidrisc...@msn.com>> Cc: Francois Rivard mailto:jeanfrancoisriv...@gmail.com>>; cnc-list mailto:cnc-list@cnc-list.com>> Subject: [EXTERNAL] Stus-List Yamaha 4hp 2 cycle Hi David, It does sound like it's running lean on the high end. The solution is likely to be related to a fuel flow problem like a clogged carburetor jet or obstruction / air leak / weak point in the fuel delivery system such as a clogged filter / fuel pickup / regulator / missing gasket / dried-up diaphragm, etc. A constructed flow problem won't manifest itself on the low end as the engine only needs a trickle of fuel to idle correctly, however when you open the throttle the trickle has to turn into a stream... Filters and hoses are easy and cheap / carburetor rebuild kits with diaphragms and gaskets cost about 15-20 bucks and take about 30 minutes to install. Good luck! -Francois 1990 34+ "Take Five" Josh and Chuck, Mixture is new with AV gas so no issues there. Only one adjustment screw on carb. Seems to only affect low throttle. As said all good in neutral and good up until ? throttle in gear. Chuck mentioned if spark plug grey and chalky, which it is, it is running lean at top end. How does one adjust top end without adjustment screw. Thanks in advance. David F. Risch (401) 419-4650 ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Stus-List Yamaha 4hp 2 cycle
Avgas is in 100 octane LL? That will eventually lead foul the spark plug, so you’ll need to check it every so often. On the plus side it doesn’t have stink perfume added to it, so if you spill it on yourself you won’t stink all day. Joe Della Barba Coquina C 35 MK I www.dellabarba.com From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Francois Rivard via CnC-List Sent: Wednesday, June 10, 2020 10:20 AM To: David Cc: Francois Rivard ; cnc-list Subject: [EXTERNAL] Stus-List Yamaha 4hp 2 cycle Hi David, It does sound like it's running lean on the high end. The solution is likely to be related to a fuel flow problem like a clogged carburetor jet or obstruction / air leak / weak point in the fuel delivery system such as a clogged filter / fuel pickup / regulator / missing gasket / dried-up diaphragm, etc. A constructed flow problem won't manifest itself on the low end as the engine only needs a trickle of fuel to idle correctly, however when you open the throttle the trickle has to turn into a stream... Filters and hoses are easy and cheap / carburetor rebuild kits with diaphragms and gaskets cost about 15-20 bucks and take about 30 minutes to install. Good luck! -Francois 1990 34+ "Take Five" Josh and Chuck, Mixture is new with AV gas so no issues there. Only one adjustment screw on carb. Seems to only affect low throttle. As said all good in neutral and good up until ? throttle in gear. Chuck mentioned if spark plug grey and chalky, which it is, it is running lean at top end. How does one adjust top end without adjustment screw. Thanks in advance. David F. Risch (401) 419-4650 ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Re: Stus-List Yamaha 4hp 2 cycle
David, There has to be an orifice (jet) or screw. Are you sure a screw isn't hidden under a plastic cowl? Get me an exact make and model so I can do some research. Josh On Wed, Jun 10, 2020, 08:08 David Risch via CnC-List wrote: > Josh and Chuck, > > > > Mixture is new with AV gas so no issues there. Only one adjustment screw > on carb. Seems to only affect low throttle. As said all good in neutral > and good up until ¾ throttle in gear. Chuck mentioned if spark plug grey > and chalky, which it is, it is running lean at top end. How does one > adjust top end without adjustment screw. > > > > Thanks in advance. > > > > *David F. Risch* > > *(401) 419-4650* > > > > *From:* CnC-List *On Behalf Of *Josh > Muckley via CnC-List > *Sent:* Sunday, June 7, 2020 10:17 AM > *To:* C List > *Cc:* Josh Muckley > *Subject:* Re: Stus-List Yamaha 4hp 2 cycle > > > > Follow my carb tuning video. Post back with questions. > > > > https://youtu.be/caIdvC8WGDg > > > > Sounds like the idle/throttle screw (T) is keeping the butterfly open too > far with no throttle applied. It just so happens that in gear there is > enough load to slow 'er down. At full throttle is sounds like probably too > much fuel (H). I think that if it was too little it would die. Since both > of these "symptoms could be a result of too much low throttle fuel (L) you > should probably start by dialing it back a bit and see how thing go. By > doing this you will lower the fuel at idle AND lower the fuel a full > throttle. If you're lucky and my diagnosis is correct then you'll kill too > birds with one stone. > > > > My advice is based on having 3 adjustment screws H (high throttle), L (low > throttle), T (min throttle). If you're missing any one of these then it > has a jet which serves in its place. > > > > Josh Muckley > > S/V Sea Hawk > > 1989 C 37+ > > Solomons, MD > > > > On Sun, Jun 7, 2020, 09:29 David Risch via CnC-List > wrote: > > So instead of giving it away I rebuilt the carb and half dozen other fixes > this winter. > > Runs and idles great, but at full throttle she bogs down continues to run, > but sounds rougher.When out gear it goes right to full throttle. > > Perhaps overpropped? > > Sent from my Android. Please forgive typos. Thank you. > > > > ___ > > Thanks everyone for supporting this list with your contributions. Each > and every one is greatly appreciated. If you want to support the list - > use PayPal to send contribution -- https://www.paypal.me/stumurray > > ___ > > Thanks everyone for supporting this list with your contributions. Each > and every one is greatly appreciated. If you want to support the list - > use PayPal to send contribution -- https://www.paypal.me/stumurray > > ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Stus-List Yamaha 4hp 2 cycle
Hi David, It does sound like it's running lean on the high end. The solution is likely to be related to a fuel flow problem like a clogged carburetor jet or obstruction / air leak / weak point in the fuel delivery system such as a clogged filter / fuel pickup / regulator / missing gasket / dried-up diaphragm, etc. A constructed flow problem won't manifest itself on the low end as the engine only needs a trickle of fuel to idle correctly, however when you open the throttle the trickle has to turn into a stream... Filters and hoses are easy and cheap / carburetor rebuild kits with diaphragms and gaskets cost about 15-20 bucks and take about 30 minutes to install. Good luck! -Francois 1990 34+ "Take Five" Josh and Chuck, Mixture is new with AV gas so no issues there. Only one adjustment screw on carb. Seems to only affect low throttle. As said all good in neutral and good up until ? throttle in gear. Chuck mentioned if spark plug grey and chalky, which it is, it is running lean at top end. How does one adjust top end without adjustment screw. Thanks in advance. David F. Risch (401) 419-4650 ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Re: Stus-List Yamaha 4hp 2 cycle
Josh and Chuck, Mixture is new with AV gas so no issues there. Only one adjustment screw on carb. Seems to only affect low throttle. As said all good in neutral and good up until ¾ throttle in gear. Chuck mentioned if spark plug grey and chalky, which it is, it is running lean at top end. How does one adjust top end without adjustment screw. Thanks in advance. David F. Risch (401) 419-4650 From: CnC-List On Behalf Of Josh Muckley via CnC-List Sent: Sunday, June 7, 2020 10:17 AM To: C List Cc: Josh Muckley Subject: Re: Stus-List Yamaha 4hp 2 cycle Follow my carb tuning video. Post back with questions. https://youtu.be/caIdvC8WGDg Sounds like the idle/throttle screw (T) is keeping the butterfly open too far with no throttle applied. It just so happens that in gear there is enough load to slow 'er down. At full throttle is sounds like probably too much fuel (H). I think that if it was too little it would die. Since both of these "symptoms could be a result of too much low throttle fuel (L) you should probably start by dialing it back a bit and see how thing go. By doing this you will lower the fuel at idle AND lower the fuel a full throttle. If you're lucky and my diagnosis is correct then you'll kill too birds with one stone. My advice is based on having 3 adjustment screws H (high throttle), L (low throttle), T (min throttle). If you're missing any one of these then it has a jet which serves in its place. Josh Muckley S/V Sea Hawk 1989 C 37+ Solomons, MD On Sun, Jun 7, 2020, 09:29 David Risch via CnC-List mailto:cnc-list@cnc-list.com>> wrote: So instead of giving it away I rebuilt the carb and half dozen other fixes this winter. Runs and idles great, but at full throttle she bogs down continues to run, but sounds rougher.When out gear it goes right to full throttle. Perhaps overpropped? Sent from my Android. Please forgive typos. Thank you. ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Re: Stus-List Yamaha 4hp 2 cycle
If it seems to lose power on the top end, that a good indicator that the engine is running lean. If your oil/ fuel mixture ratio is off with too much oil, your “fuel” may not have enough gas to mix with oxygen to provide enough power. A good way to determine a lean burn is 1. Check the spark plug color. If it looks gray or chalky, you might be too lean and 2.when you run the engine at full throttle and back off the throttle a touch and the engine speeds up, it is too lean on the top end. Check for leaks around the carb and intake manifold. Spray a little starter fluid Near the manifold and if the eNgine speeds up, you have an air leak. Should you find the plug to be black and Sooty, you have the opposite problem, too rich. Again , check mixture ratio. Not enough oil in the premix can make a difference, causing incomplete combustion at full throttle. Finally, modern gasoline doesn’t mix well with oil and alcohol tends to separate the oil from the gasoline. That can mess with your fuel as well, making part of the fuel storage critical to a good running motor. Aren’t engines fun? Chuck Gilchrest Half Magic Padanaram MA Sent from my iPhone > On Jun 7, 2020, at 9:29 AM, David Risch via CnC-List > wrote: > > > So instead of giving it away I rebuilt the carb and half dozen other fixes > this winter. > > Runs and idles great, but at full throttle she bogs down continues to run, > but sounds rougher.When out gear it goes right to full throttle. > > Perhaps overpropped? > > Sent from my Android. Please forgive typos. Thank you. > > ___ > > Thanks everyone for supporting this list with your contributions. Each and > every one is greatly appreciated. If you want to support the list - use > PayPal to send contribution -- https://www.paypal.me/stumurray > ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Re: Stus-List Yamaha 4hp 2 cycle
Follow my carb tuning video. Post back with questions. https://youtu.be/caIdvC8WGDg Sounds like the idle/throttle screw (T) is keeping the butterfly open too far with no throttle applied. It just so happens that in gear there is enough load to slow 'er down. At full throttle is sounds like probably too much fuel (H). I think that if it was too little it would die. Since both of these "symptoms could be a result of too much low throttle fuel (L) you should probably start by dialing it back a bit and see how thing go. By doing this you will lower the fuel at idle AND lower the fuel a full throttle. If you're lucky and my diagnosis is correct then you'll kill too birds with one stone. My advice is based on having 3 adjustment screws H (high throttle), L (low throttle), T (min throttle). If you're missing any one of these then it has a jet which serves in its place. Josh Muckley S/V Sea Hawk 1989 C 37+ Solomons, MD On Sun, Jun 7, 2020, 09:29 David Risch via CnC-List wrote: > So instead of giving it away I rebuilt the carb and half dozen other fixes > this winter. > > Runs and idles great, but at full throttle she bogs down continues to run, > but sounds rougher.When out gear it goes right to full throttle. > > Perhaps overpropped? > > Sent from my Android. Please forgive typos. Thank you. > > ___ > > Thanks everyone for supporting this list with your contributions. Each > and every one is greatly appreciated. If you want to support the list - > use PayPal to send contribution -- https://www.paypal.me/stumurray > > ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
Stus-List Yamaha 4hp 2 cycle
So instead of giving it away I rebuilt the carb and half dozen other fixes this winter. Runs and idles great, but at full throttle she bogs down continues to run, but sounds rougher.When out gear it goes right to full throttle. Perhaps overpropped? Sent from my Android. Please forgive typos. Thank you. ___ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
