Date: Mon, 11 Apr 1994 12:37:50 EDT
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: cchubb@ida.org (Chris Chubb)
Subject: Truoble Tuning Mixed up engine! (long)
I am having some trouble getting a good tune with the mixed-up
engine that I now have. Because of the fire I had in Feb., I
have the following setup:
1600 DP. 1971 Type II version.
Pure-Vacuum distributor (from a '69 Bug, I think) (No mechanical advance)
30-PICT-2 carb.
I have all the parts installed, and am having a hell of a time
getting them all tuned up. When I timed the distributor, I put it
right on the notch on the pully. But Looking at the book, it lists this
notch as being 7 degrees ADTC (Because of the vacuum retard that was
standard with this model) So TDC is a little to the RIGHT of this notch.
Correct? The distributor comes from a Bug that wants to be either
5 or 0 degrees BTDC. So which timing mark should I use? (No degree
wheel on the pully, so I have to measure everything.) I time it
dynamically with no vaccuum hoses hooked.
When I had the notch on the seam, it ran terrible, could not get it
to go over 3000 RPM, and when I hit the gas, even a little, it wanted
to die until it sped up to 2000, then it was smooth. So I checked the
timing diagrams and discovered the above disparity in timings. So now
I have about 3-4 degrees BTDC timed in there. As best as I can tell.
That makes it run a little better, but now it is getting real hot.
The gauge creeped up with just a little 2 minute ride. Heat
from bad tuneup is usually either timing or bad mixture. So that
brings me to the carb. (dwell is 50 degrees)
The 30 PICT 2 is harder for me to tune than the 34-PICT-3. I dont know
how far out the one screw should be to be mixed about right. I tried the
turn in (slows down) turn out, (til fastest), then a turn more. But at
this level, the engine is just running too fast, no matter where the
throttle positioner is. (like 1000 rpm) I am afraid that if I turn the
mixture valve in enough to slow it down, I will lean out the mix and
fry the engine. The mix doesent feel too lean (I decelerated down a steep
hill in first at 15 MPH, foot off the throttle, and no popping or backfire.)
But the manual shows a much smaller main jet in the 30 PICT 2 than in the
32PICT (on there before the fire) or the 34-PICT-3 (stock).
So the next step was to question the distributor. So I decided to try the
old one that was on there from before the fire. I rummaged around and came
up with another set of points, and old condensor, and an ancient cap and rotor.
Put all the parts back on as well as I could, checked the vacuum and centrifigul
operation, and tried putting it back in. I tried the center wire, andI was
getting plenty of spark. But then I could not get the car
to even start. I timed it as well as I could statically, and set the dwell to
be 50 degrees, as per the dwell meter. (indespensible tool) But when I time it
statically and take the cap off, the rotor is smack dab between the two wires.
When I swap Cyl #1 wire between the two that is is between, it either backfires,
postdetonates, or just does not start. So back in went the pure-vacuum dist.
I am now in a serious quandary. I dont know what to do about tuning up the
engine. I have never had this much trouble with getting something to
run passably.
Should I keep trying with the old distributor? (Why is the rotor BETWEEN plugwires?)
Should I blow $50 to get a 009, even with the tiny carb? Does someone have
a rebuildable 34-PICT-3? (Local Bug Man wants $85 for one off the pile, $150 for
a rebuilt one, what a ripoff) I just want my cheap, dependable, slow
transportation back, dammit. I used to be able to jaunt off to Florida,
from Washington DC, without a worry. Now I had to arrange a chase car
just to escort me to the gas station. FRUSTRATING!
--- Chris Chubb (cchubb@ida.org)
__________________________________________________________________________
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\for Defense Analyses, the US Government, or anyone else. \
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