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wolfej1
Samba Member
Joined: August 15, 2005
Posts: 679
Location: North Royalton, Ohio
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 Posted: Tue Nov 17, 2009 9:48 am Post subject: Any thoughts on this one? |
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My 82 Westy had been sitting for a while without being started. Normally it has to be cranked a bit to get it started, it idles rough with some hunting, smells rich, and the idle will kick up if I rapidly depress the brake pedal. Once it warms up it is better but I still get sub optimal fuel economy.
So I will get to the point now. 2 days ago I went to start it up and it kicked over like a new car, idled good, was not rich - but the valves were clacking away loudly - and the weather was a bit colder than the last time I started it. In essence it was great except for the sound. So i drove it a while and the valves quieted down and it ran great.
Next day I go to start it and the valves are quiet but it is the exact same condition as described in the first paragraph. The weather was essentially the same.
Wondering if there is some connection between the valves being loud and the good startup/idle performance.
Anyone experienced anything like this?
Regards...
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1982 Westy
2004 KDX200
2008 Kawasaki KLR 650
1979 Yamaha DT 175
1995 Toyota 4Runner |
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j_dirge
Samba Member
Joined: August 08, 2007
Posts: 4641
Location: Twain Harte, CA
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| Posted: Tue Nov 17, 2009 10:03 am Post subject: Re: Any thoughts on this one? |
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| wolfej1 wrote: |
Anyone experienced anything like this?
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Yes.. in fact, I'd suggest the cold start after sitting valve noise is more the norm than the exception on high miles WBXers.
If I let my van sit for more than a day or two, it starts with noisy valves.. quieting down as it gets warmed. If I drive it regularly the starter works hard but it runs like a top from the get go.
There's been a fair bit written on the valve noise subject.. lots of folks blame the oil filter (personally I don't belive it makes a difference which filter you use)..
But I think 10cent explained it best. There was a thread some 1.5-2 yrs ago on this.
Try a search.
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-89 GL Westy, SVX.. finally.
-57 pan f/g buggy with a 67 pancake Type 3 "S"
"Jimi Hendrix owned one. Richard Nixon did not"
-Grand Tour, Season 1, episodes 4 and 5
| danfromsyr wrote: |
those are straight line runs with light weight race cars for only 1/4mile at a time..
not pushing a loaded brick up a mountain pass with a family of 4+ inside expecting to have an event free vacation..
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wolfej1
Samba Member
Joined: August 15, 2005
Posts: 679
Location: North Royalton, Ohio
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| Posted: Tue Nov 17, 2009 10:56 am Post subject: Re: Any thoughts on this one? |
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| j_dirge wrote: |
| wolfej1 wrote: |
Anyone experienced anything like this?
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Yes.. in fact, I'd suggest the cold start after sitting valve noise is more the norm than the exception on high miles WBXers.
If I let my van sit for more than a day or two, it starts with noisy valves.. quieting down as it gets warmed. If I drive it regularly the starter works hard but it runs like a top from the get go.
There's been a fair bit written on the valve noise subject.. lots of folks blame the oil filter (personally I don't belive it makes a difference which filter you use)..
But I think 10cent explained it best. There was a thread some 1.5-2 yrs ago on this.
Try a search. |
Thanks for the info...i appreciate it but my issue is not the noise, What I am wondering if there is any corrolation between noise and starting and idling performance. Like I originally stated, when it makes noise it starts and idles better, but when it doesn't it idles and starts like crap.
I am thinking that the valves being airlocked are somehow making it idle and start better - which would indicate something with the valve adjustment........strange...
_________________
1982 Westy
2004 KDX200
2008 Kawasaki KLR 650
1979 Yamaha DT 175
1995 Toyota 4Runner |
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MarkWard
Samba Member
Joined: February 09, 2005
Posts: 18754
Location: Retired South Florida
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| Posted: Tue Nov 17, 2009 11:05 am Post subject: |
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| This is a stretch, but if the valves are clacking, they are sitting on their seats longer. The valve clearance has lowered the lift and duration. More time for the compression to build. Easier starting. So yes, it is a stretch, but loose valves could help it start. On my 68 Type 2, I would run the exhaust valves at .008". My reasoning was that the exhaust valves would sit on the seat a little longer to dissipate the heat better. More of a peace of mind than anything I could prove. |
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reluctantartist
Samba Member
Joined: August 13, 2006
Posts: 1929
Location: Bloomington, IN
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| Posted: Tue Nov 17, 2009 12:41 pm Post subject: |
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When hydraulic valves sit for a while they will make noise when you start up as they pump back up (this is normal you do not want clacking valves after they pump up). It still sounds like you have a vacuum leak ...the brake pedal pressure is a good indicator of it. It could be the brake boost, the vacuum canister on the distributor, decel valve, crack in a hose or air intake boot, PCV valve, leaking gasket, etc. Is your one way valve for the brake boost working correctly?
Too bad you are not closer. I would hook up my air hose and pressurize the vacuum system and find what is leaking.
Good luck.
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1982 Westy, 1974 412 Variant... Yes, Aircooled's are great! Oh and I do have modern computer controlled vehicles too, but I just don't care about them. |
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FNGRUVN
Samba Member
Joined: October 27, 2007
Posts: 2237
Location: Fort Collins, CO
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| Posted: Tue Nov 17, 2009 9:05 pm Post subject: |
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What are you getting for MPG? My '80 Westy gets about 18. Have you done all the checks and tests on the FI system that's outlined in the Bentley and VW Pro Training manuals, adjusted the valves, compression test and all the other basics? I would think a vacuum leak would cause it to run lean if anything. My van runs good whether the valves are noisy or not.
Do those tests and I bet it pinpoints your problem. Could be as simple as a broken wire in the engine harness.
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"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." - Benjamin Franklin |
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Wildthings
Samba Member
Joined: March 13, 2005
Posts: 52338
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| Posted: Tue Nov 17, 2009 9:14 pm Post subject: |
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| I think you have a mixture problem. When you get extra air like when you put your foot on the brakes, you are affecting the already messed up mixture and getting a change in idle speed. The same with the engine running with the valves leaked down, this too is affecting the mixture and compounding your other mixture problems. |
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