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Subject:Re: Ping/Knock/Detonation
From:John Rodgers
Date:Sat, 20 Jan 2007 20:39:17 -0600

Jake, that method sounds interesting. Would you please expand on it a
bit. I have  a small ping in a certain range under load as in climbing a
big hill. Have nto been able to get rid of it. This might do it.

Thanks,

John Rodgers
88 GL Driver

Jake de Villiers wrote:
> You might try the total timing method Michael.
>
> Set the timing with an advance timing light to the total required
> advance at
> 2500-3000 RPM and treat the resultant advance at idle as an artifact.
>
> I've used this method on many modified engines over the years to good
> effect.
>
> Jake
>
> On 1/20/07, Michael Diehr <md03@xochi.com> wrote:
>>
>> The rebuild & install was done by a shop (who I won't name but I hear
>> is of extremely dubious reputation I'm told -- I was aware of that
>> going in but a move forced my hand) and I have no idea what they did
>> or did not do when installing the 2.1 into my 85.    I believe that
>> when I got the rebuild home, I measured the timing at idle as per
>> bently (DIS disconnected etc.) and it was spot on.   However, that
>> was 4000 miles ago.
>>
>> Anyone on the list have an opinion as to how much total time pinging
>> it would take to fry my engine?   1 second?  10 seconds?  10
>> minutes?     Should I just assume the engine is toast, find a new
>> mechanic, drop the van off, and fly home?   :-)  Anyone know when the
>> Zetec conversion will be CARB approved?
>>
>> On Jan 20, 2007, at 11:10 AM, Dennis Haynes wrote:
>>
>> > Did you convert to the cooling system with the oil cooler to also
>> > cool the
>> > pistons? Detonation is extremely speed and load over time
>> > sensitive. The 1.9
>> > FI system should not be a problem, both use the same injectors. Is the
>> > timing set to spec or slightly advanced? Get it set back down. Make
>> > sure the
>> > vacuum retard on the distributor is working to reduce the timing
>> > during part
>> > load to reduce the peak flame temperatures. Pinging actually occurs
>> > long
>> > before you hear it. While pinging, you working at busting rings,
>> > melting
>> > pistons, and burning valves or even cracking heads. This is where
>> > EGR could
>> > be helpful but the Vanagon does not have it.
>> >
>> > Dennis
>> >
>> >
>> > -----Original Message-----
>> > From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
>> > Behalf Of
>> > Michael Diehr
>> > Sent: Saturday, January 20, 2007 1:02 PM
>> > To: vanagon@GERRY.VANAGON.COM
>> > Subject: Ping/Knock/Detonation
>> >
>> > I'm finishing up a long (3K miles) road trip and the van has been
>> > running like a champ (for the first time ever, wahoo!).   However,
>> > I've noticed a problem with pinging (aka knock aka detonation).
>> > It's very particular -- it only happens at 1/2 throttle or higher at
>> > 3200 thru 3500 rpm, even on 91 or 92 octane gas.   Happens most of
>> > the time -- only exception seems to be at temperatures of 30F and
>> > lower at 3000F altitude or higher, which seems very consistent with
>> > it being ping (heat & pressure related).
>> >
>> > As far as I know, the timing of the engine is good at idle, but I
>> > doubt that the advance has ever been tested.
>> >
>> > This is a 85 westy automatic with a newly rebuilt 2.1L block
>> > installed (about 5k miles post rebuild).  It has the stock 1.9FI
>> > system, including a rebuilt computer & distributor & afm.
>> >
>> > It seems weird to me that the RPM range is so specific -- it really
>> > only does it at that particular RPM range.  Any ideas?   Bad
>> > distributor advance?   Flat spot in the AFM?   1.9L FI system not
>> > well matched to a 2.1L block?
>>
>
>
>
> --
> Jake
> 1984 Vanagon GL
> 1986 Westy Weekender "Dixie"
> www.crescentbeachguitar.com
>
>