Date: Wed, 18 Jul 2012 20:24:36 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Emissions: Vacuum Leak ID'd 82 aircooled westy
In-Reply-To: <CACynUEN451dKtGgYe5YU7BWPLioT7WsiOy8cFz0Z_iaM08v1cg@mail.gmail.com>
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It is rare for the intake gaskets to leak if the correct ones are used. I
have seen leaks where the tubes join into the castings. Check for leaks at
the injector.
As for the failure limits the 220 ppm is already a real gross failure and is
common limit for vehicles that age in most inspection programs. If all is
well the reading should be near zero. Even without a cat a healthy engine
should run near 50 or better.
A sizeable vacuum leak near one cylinder can cause that cylinder to run lean
leading to a burned valve or piston. The air cooled engines have little
tolerance for these types of problems. The installation should have included
thorough test and set up including cylinder performance/balance testing.
Recently I meet a person at a camp out with a recently acquired camper.
Supposedly the engine only had 7,000 miles on it. When he showed it off to
me I explained that I though the engine sounded terrible and that it really
needed servicing right away. He left the campout a few hours before me. I
met him on the side of the expressway on my way home. The engine overheated
to the point it stopped running. Got it towed home for him. He removed the
engine himself and tore it down. Signs of heads and pistons melted. Yes it
can happen that quick.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Ken Wyatt
Sent: Wednesday, July 18, 2012 4:05 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Emissions: Vacuum Leak ID'd 82 aircooled westy
Greetings Vanagonauts,
I've been having trouble meeting the hydrocarbon standard on my AFC
2.0 l aircooled engine here in Salt Lake City, UT. Its a fairly new engine
with only about 6000 miles. It's hydrocarbon output is about 4 times higher
than it should be at 800 ppm instead of 220 ppm or lower., The emission guy
said he thought it was a vacuum leak near the right head looking forward.
(He sprayed carb cleaner around the
engine I guess) So in my efforts to achieve emission compliance, I
have isolated a slight vacuum leak at the #4 intake manifold right at
the cylinder head. It revs slightly when I hit it with starting
fluid. I tried to simply tighten the intake manifold bolts a bit but that
didn't do the trick. I'm wondering if others have had such a leak and would
new gaskets likely solve this issue or is it perhaps more complicated than
it appears like as warped head or something.
Thought??
TIA
Cheers
Ken Wyatt
82 westy
SLC, Utah
(where emission stds rival CA I think!)