Re: Perhaps you could provide some insights?

["Melissa & Jim" <jadney@vwtype3.org>]

>From your description I don't think you are on the Type 3 list.  
Perhaps you should be.  So everyone can get in on this question I am 
posting it back to the list as well as to you.

On  7 Dec 97, Brant E. Herman wrote:

> From the brief bio in your piece on the Type III web page, I was hoping
> you could spare a few minutes reading about my plight.  I own a '69
> squareback and am suffering from excessive smoking.  It all started a
> month ago when the engine was running very haphazardly and power was
> minimal and randomly occurring.  I took it in to the shop and they put
> in a used temperature sensor which connects to the ECU.  That fixed it
> for a few minutes until the sensor got screwed up and I had to give it
> back to them so they could put a new temp. sensor in.  They did this and
> the car was still smoking, but running better.  What the mechanic told
> me was that when the sensor was busted, excess fuel went into the
> combustion chamber and did not ignite, thereby flowing around the piston
> into the cylinder.  My mech. told me that this may have washed the oil
> off the inside of the cylinder and allowed the engine to wear away the
> hatchmarks on the inside of the cylinder.  I just got back from talking
> to him about this further and he reccomended that I change the oil to a
> higher weight.  I put in 50w oil to see if that filled the gaps in the
> cylinders.  Still a good deal of smoke when the throttle is depressed. 
> They also suggested using "magic dust."  Putting Comet cleanser, less
> than a tablespoon into the air intake butterfly valve while the engine
> was running.  They said this sometimes scratches new grooves in the
> cylinders, reducing the smoking.  So that is where I stand at this
> point.  With a car that runs well, sounds good and looks just fine, but
> smokes like a chimney. 
> I was hoping you could spend some time thinking about the possible cause
> of this smoke.  You could say that I am willing to change the piston
> rings and have the cylinders machined again.  Would that be the key or
> are there cheaper ways to check other potential problems.  

> brantherman@earthlink.net

Excessive smoking is usually caused by excessive richness.  There are 
many causes, and the excess gas CAN cause abnormal wear on the 
cylinder walls (loss of the crosshatching, etc.)  However, I have 
never heard of anyone suggesting that it would be a good idea to try 
fix this by pouring a bit of Comet down it's throat.  I would suggest 
that you RUN, don't walk, but RUN as fast as you can in search of a 
better mechanic.

I think it is quite likely that you have a FI problem.  There is no 
point in worrying about the cylinder walls before you fix the FI.  
You need to find someone that still remembers Bosch D-Jetronix fuel 
injection; it was last used in new cars over 20 years ago.  

Have you studied the Bentley manual?

Volkswagen Official Service Manual
Type 3 Fastback and Squareback 1968-1973
published by Robert Bentley, Cambridge, Mass, 1974
ISBN 0-8376-0057-X / LPV 997 383 / VSQU
(excellent book, complete and well written)

join the T3 list: send email to:

gregm@umich.edu, 
subject subscribe T3 list

You need to explain the depth of your expertise and where you are 
located.  Perhaps you are close to someone on the list who can help.  
It is almost impossible to diagnose without good data via email.

A couple things to check.

Is it using oil?  Or does the oil level seem to be rising as the 
excess gas dilutes it?

Check the charging system regulating voltage at fast idle.  It should 
be 14.1-14.4 V.  If it is below 13.5 V replace the voltage regulator; 
low system voltage will make the EFI run rich.

Your experience with the temp sensor has demonstrated that the sensor 
is not at fault.  Which sensor was it?  (there are two temp sensors.)

Do you have gas that spills out from behind the right front wheel if 
you fill up the tank all the way?  If so your overflow hose is 
cracked and there is a good chance that you have a fair amount of 
water and dirt in the tank.  Replace the hose, 311-201-179A, I stock 
these.  It is important!

Join the list.  Give us more details.

Jim
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       Melissa Kepner                                    Jim Adney
                             Laura Kepner-Adney
                         jadney@vwtype3.org      
                             Madison, Wisconsin
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