Date: Thu, 26 Sep 2002 15:09:21 -0400
Reply-To: dr <dxrobertson@NETSCAPE.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: dr <dxrobertson@NETSCAPE.NET>
Subject: Re: Bad Valve Issues/Question, Opinion sought.
Content-Type: text/plain; charset=us-ascii; format=flowed
I am not sure how they determine that the valves are bad, by just
disconnecting the plug wires. It could be the injectors in those 2
cylinders are bad. I just went through this myself, on my 82 air cooled.
I didnt have the hot start problem you have, but I was just checking the
plugs and injectors. Here is what I did-
I disconnect each plug wire individually and the rpm would drop about
500 for each.
I then disconnected each injector plug, and got about the same results.
I then removed each injector pair from the intake a side at a time,
leaving the wire and fuel hose attached, placed a plastic peanutbutter
jar (just happened to be a good size) under each injector. Disconnect
the coil wire. Then ran the starter to watch the injector pattern. I
found that one injector was barely emitting any fuel at all, and one was
streaming out with fuel, even after shut off.
My point is that even though I disconnect the plugs and injectors, and
got an rpm drop; I had, in my opinion, 2 bad injectors. I never would
have known this unless watching the spray pattern of the injectors.
Your compression is better than mine; I have one cylinder at 98. The
others around range 105 up to 120. Not real good, but it runs.
For hot start problems, make sure your injectors are not leaking after
you shut down (including your cold start injector - it shouldnt run at
all at hot start), check your fuel pressure after you shut down, is it
bleeding off?
david
Jeff Strickrott wrote:
> Hi All:
>
> I have a question regarding testing for bad vales. Here is the history.
>
> I have an 82 Vanagon with 50k original miles. As I have been
> reconditioning it, I have been battling a hot start problem. That is the
> engine must be turned over for about 8-11 sec's and the gas peddle used
> to get it started when the engine has warmed up. I have gone through all
> the Bentley's checks on the fuel injection components and have found
> nothing wrong. In the process I have replaced all the gaskets/hoses
> around the air distributor. My engine vacuum is 14.5-15 inHg @ 850 rpms.
> It has new points/plugs/cap/rotor. Old plug wires and coil, but the coil
> and engine spark seem to be strong enough.
>
> I finally gave up and took the car this morning to a local garage that
> works on bugs/buses (first time visit) to see if they could solve the
> problem. Their opinion was that the car was not running on cylinders 1&2
> because if they removed the ignition wires on 1&2 it did not effect the
> idle of the engine. They did a compression test on these cylinders and
> got 100 psi. They also checked the FI and concurred that the system
> seemed to be working. Their conclusion is that the valves are bad on
> cylinders 1 &2.
>
> Not ever having driven an air cooled van in its prime, I have nothing to
> compare the performance/power of the engine to. But I think I would have
> noticed if it was only running on two cylinders. The car seems to have
> enough power to get up to speed on the highway (65) and to handle hills.
> How could I double check their diagnosis? Could someone explain what
> would make the valves go bad so early in the engines life? Was this
> normal?
>
> Thanks in advance for the opinions.
>
> Regards,
> --Jeff Strickrott
> 82 Westy, South Florida