I know this may sound crazy but, are you checking the timing on the correct
cylinder? Just a thought. On some older engines (A friends International)
the timing is referenced to number eight instead of number one.
Like I said, just a thought. Other thought.............Stock balancer or
replacement?
----- Original Message -----
From: Doug Clark <dougmclark@hotmail.com>
To: <tigers@autox.team.net>
Sent: Wednesday, January 26, 2000 6:14 PM
Subject: Timing Advance-no tiger content
> Hi Gang,
> A year ago I helped a friend drop a new 225ci V6 into his 67 Jeepster.
> He has heard me brag about the people's knowledge this list and has asked
me
> to forward this question.
>
>
> There are several guys in our group that have a total mystery in our 225
> odd-fire Buick V6 motors. Most of these are in '67-'73 Jeepster
Commandos,
> or early CJ's, but one is even in a boat. To my knowledge this "problem"
> doesn't exist with the Buick 231 either odd or even-fire motors.
>
> The symptom:
> The engine has an initial timing of 30-40 degrees BTDC!! The original
> setting is supposed to be 8-12 degrees.
> If running a points distrib. there is about 12 degrees of vacuuum
advance,
> + 18 degrees of mech. advance. In mine, starting at 37 degrees, this
yields
> a total advance of 67 degrees! I CAN NOT retard below 30 or the engine
will
> stall. HEI conversion yields the same result. The engine seem to run
> fine, with decent mileage, but perhaps the low end power is compromised.
>
> What we've checked:
> Initial thought was that the harmonic balancer is off. Pull the head, set
> to TDC and the piston is squarely at the top.
> Timing chain off a tooth. Nope. Bad cam? Seems unlikely since we have
> different manufacturers, but the guy with the boat degree'd his and says
> it's right on.
> All of these have low restriction exhaust pipes (mine has a flowmaster
going
> into 2 1/2 in pipe instead of a muffler) and the guy with the boat is
> running straight pipes. We thought of backpressure, but these engines
fire
> up immediately and I would assume that this is before any back pressure
> could have an effect. Same would be true for a massive internal vacuum
> leak.
> Plugs look clean and uniform in color. All have spark. Serial numbers
off
> the dist was used to verify correct cap/rotor/points/condensor (there in
an
> even-fire version for the HEI, and several different caps for the Delco or
> Prestolite points setup depending on year).
> If you know about odd-fire motors, you know that if you ran even-fire
> ignition, 2 cylinders would fire at the correct time, 2 a little off and 2
> WAY off. But compression is equal in all cylinders and when I pull the
plug
> wires, I get a drop of 50 RPM from each one. If it were 2 cylinders that
> were firing at the wrong time, I would get less of a drop with some, more
> from others.
> All the motors, to my knowledge are 0.030" over, but there doesn't seem
to
> be a common thread. If anyone has even heard to this happening please let
> me know. I'm no pro, but some very experienced mechanics are stumped
after
> spending MANY hours under the hood (I'm sure no one EVER spends time on a
> Tiger, right? ;-) and at this point we're looking for help.
> Sorry to be off-topic and long-winded, but if you have any ideas I'd love
to
> hear them.
> Thanks,
> Michael
> mderksen@microcide.com
>
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