What if there was a little varnish or other debris on the check valve in the tappet. The varnish would allow the tappet to function "normally" when fed pressurized oil but would "leak down" fairly easy thus creating the clatter after a hot start. Just conjecture but interesting to think about.
On Mar 15, 9:41 pm, Dennis Hammerl <[email protected]> wrote: > If the adjuster had failed, no amount of oil pressure would make it SHUT UP. > If yours quiets down some times, what do you think ? > > --- On Sun, 3/15/09, tharrisn <[email protected]> wrote: > From: tharrisn <[email protected]> > Subject: [Nighthawk Lovers] Re: NOISE cont. > To: "Nighthawk Motorcycle Lovers!" <[email protected]> > Date: Sunday, March 15, 2009, 9:08 PM > > Ok, it's get the oil pressure checked first. > > It's gonna take me a bit to get back to this project. I'm helping > escort a group of teenagers on a back packing trip. Should be fun...I > think I'm the token old guy? <grin> > > On Mar 14, 11:33 pm, Dennis Hammerl <[email protected]> wrote:> A great > question. Before we get into that, I would call your attention to > > the location of the oil pressure sending unit and the fact that the upper end > (cams, etc) are the last to get oil. That's why I'm so aghast at gonzo > RPM starts. With that in mind, it's not too difficult to see that the light > can go off (oil pressure good) long before the critical upper end parts get > lube. Many years ago we would start a cold CB450 in the garage with no radio > on and the door closed. At exactly 58 seconds after start-up, it would > suddenly > get very quiet. It took that long to oil the upper end ! Lets not speculate on > any damage without a real pressure check first. I know that going anywhere > near > a dealer is like being condemned to hell, but suck it up and take this > variable > out of the equation. In the end you may have to remove the head cover just to > examine the problem. Not yet. > > > --- On Sat, 3/14/09, tharrisn <[email protected]> wrote: > > From: tharrisn <[email protected]> > > Subject: [Nighthawk Lovers] Re: NOISE cont. > > To: "Nighthawk Motorcycle Lovers!" > > <[email protected]>> Date: Saturday, March 14, 2009, 11:02 PM > > > Would low oil pressure cause other noticeable problems besides the > > tappet noise? > > > I know "idiot" lights on cars are notoriously bad at indicating > > problems but what about our bikes? I ask because the light comes on as > > it should when turning the ignition on but promptly goes off when the > > engine starts. > > > On Mar 14, 2:06 pm, Dennis Hammerl <[email protected]> wrote:> > > This is starting to sound like > > an oil pressure leakback, caused by #1 thin oil (from heat) or that #2 > > the Sea Foam has loosened up some grunge that is unable to escape from that part of the system since a I described, is not open-ended. Now on the #1 cause, I'd get a dealer to check its real oil pressure when hot. There is a screw in gauge that dealers have to do this. > > Shouldn't cost much to check. Low oil pressure can be many things. Don't panic. Since you didn't use anything on the second oil change we can't accuse anything of diluting the oil. > > > > > > --- On Sat, 3/14/09, tharrisn <[email protected]> wrote: > > > From: tharrisn <[email protected]> > > > Subject: [Nighthawk Lovers] Re: NOISE cont. > > > To: "Nighthawk Motorcycle Lovers!" > > > <[email protected]>> Date: Saturday, March 14, > 2009, 11:17 AM > > > > Doesn't sound like all the tappets are noisy but a few and not > all the > > > time. They are the loudest after the bike is hot and sets for ten minutes > or so. > > I can almost guarantee when I start it back up and take off the noise will > be > > very pronounced until it eventually quiets back down after a mile or two > > (quicker if I rev it a bit). They'll stay quiet until it idles for > some time > > or I shut if off and start it again while still hot. I've changed > oil and > > filter twice now in 800 miles. The first change I added SeaFoam (1/3 can). > > Second change straight engine oil (Shell 5W-40 Rotella-T). I'll make > the > > next change using Marvel Mystery Oil. I've never used MM Oil before. > How > > much can I safely put in the engine of this 83 650, or just follow > directions on > > can? Will it hurt anything if I continue to "soup up" the > engine oil > > at each change with MM Oil no matter how long it takes to stop the tappet > noise? > > If I change oil at say 300 to 500 miles the next several> times do > > I need to change the oil filter too or can I skip to every > > > > > other change while working on this problem? I'm going to give the > engine > > every opportunity to purge it's little gremlins before taking more > drastic > > measures like pulling the cylinder head cover. But, I'm collecting > some > > spare parts should I need to dig deeper. You have helped a bunch! Thank > you. > > On Mar 13, 10:42 pm, Dennis Hammerl <[email protected]> wrote: > > I > > guess I stirred something up. I did check parts sites and found no new > parts > > available. (that puzzles me, I never used any) They don't wear out and > you > > can purge them. There is a tool for purging the air that you don't > need, > > just makes it easier. Let's start here; do they (one or more) tap all > the > > time, some of the time, once in awhile ? For the always and often cases, > you may > > have to remove and purge. For the once in awhile, CHANGE OIL... then > change it > > again. Get the nasties out. The 3K RPM deal is to force out the> > > particle. In practice, consider the adjuster like an oil pressure gauge. > > > > > It's a dead-end that reacts to pressure. They do leak some out of the > bore > > and back into circulation. I change my oil every thousand miles. Comes out > like > > it went in. Seems a shame but the alternative would be more so. My one > 700s > > started to tap on a trip and without any option, I continued to ride it > home. It > > stopped some miles later and I changed the oil next day. > Never > heard from > > again. Any top-end work and I remove them and place right-side up till I > > reinstall. Somebody once tipped over a few and I had to purge them before > > replacing in motor. If the problem persists and needs attention, the > offending > > ones are easy to identify. To save time, use a screwdriver as a > stethoscope and > > get a good idea of it's general location. There should be no clearance > at > > any valve. Since they retain oil, the ones that are really hard to push > down are > > good. Without oil, you are pushing against> a spring only. (still, a > > tough one) Now removing it is a chore. As I am > > > > > want to do, I recommend to degree in the cams on any bike with high > mileage if > > you have any reason to remove them. The results are well worth it. > Bleeding the > > air out of an adjuster is a simple process where you insert an object into > the > > hole in the end and while holding it under in a bowl of oil, work the > piston > > till the bubbles stop coming out. Hold upright and install. > I once > got a > > Hawk in that had been laying on it's side for a long time... uh oh. It > > started and rapped like mad for about 3~4 minutes. Once it quieted down, > we > > changed oil and filter, sent it on it's way. You have to make the call > as to > > what you want to do / can do for your problem. Everybody has thier own > snake > > oil, I'm going to recommend Marvel Mystery Oil added to whatever you > use. > > It's quite good at cleaning. One pint in my '86 700s does it for > me. > > (that year has the largest sump) It is possible one could> fail, they > > are after all a mechanical device. That one would feel > > > > > "not right" when purging. As in sticky, not smooth.Or a broken > spring > > inside. > Any of this rambling help ? --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en -~----------~----~----~----~------~----~------~--~---
