[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]

Re: [T3] Dumb Ass Thing to do


On 10 Dec 99, at 9:08, Chris Picknally wrote:

> (This is the dumb ass part) It broke off! Yes that's right, as the piston
> was coming up to the top it broke off about 3 inches (guess) of the "FXXXing
> stick"!  The portion of the stick in the cylinder is about 1/8" tapering to
> 1/16" it is very brittle as I found out. Due to the angle it wedged itself
> and broke  I guess.

Sorry, I guess I should have warned you about that. It's best to get 
close to TDC before you stick your probe in there, or just watch the 
probe all the time and make sure that it stays horizontal, or 
sometimes I use a screwdriver and the weight of the handle keeps it 
level, but if you manage to jam a metal probe in there you risk 
damaging the spark plug threads.

> What do I do now? Do I run it in hopes of it breaking up and getting
> expelled out the exhaust?

I doubt if your situation is as bad as it seems right now. I would be 
tempted to see if you could fish the wood bit out by some clever 
trick, like feeding something sticky in there and pulling it out. 
Just be sure that you don't run anything in there that has any 
possibility of not coming back out, and you probably don't want to 
transfer any sticky stuff to the cylinder walls Can you turn that cyl 
past TDC? If so, then I doubt that there is any problem with just 
starting up the engine (with that spark plug out) and letting it 
digest the wood. They seem not to have any problem with the brass 
throttle pump jets, after all. 

I suggest leaving the spark plug out initially only to give another 
escape route for the wood chips and to avoid damage to the spark plug 
tip, which is relatively fragile.

The ONLY problem with just starting the engine up would be if the 
wood were thick enough that it could jam sideways between the piston 
crown and the head and wouldn't compress enough to let the piston go 
past TDC. If the piston catches it end on the wood will shatter and 
your problems are over. Once shattered, the 

> How long would it take to pull the head, do I have to remove the engine from
> the car?

You CAN do it in the car, but it is harder and it takes longer. Pull 
the engine if you choose this route.
 
> TOP DEAD CENTER Question While I'm here:
>     So with my wonderful stick I find that the piston reaches the peak on
> the compression stroke just about when it hits the very 1st mark on the
> pulley ( 4 marks one large with 3 more to the right of the largest.) This is
> the mark furthest to the passenger side. I realize that the piston stays at
> the peak while the crank follows through the stroke. The piston starts to go
> down as soon as the largest mark centers on the case mark. My question is at
> what point is TDC, when the piston first meets the peak or just before it
> comes down. 

To do a good job with this method you have to approach TDC from BOTH 
directions and take the midpoint of the two results. This is all 
because there is VERY LITTLE motion of the piston as it is going past 
TDC (sin (zero)=zero, etc.)  Another way to do this is to knock the 
ceramic out of an old spark plug and weld/braze a 1/2" extension on 
the inside end. Round the end smoothly and screw it snugly into the 
#1 cyl (when the piston is AWAY from TDC. Then carefully bring the 
piston up until it contacts the probe end. Mark that point on your 
pulley, then reverse direction and do it again, coming up from the 
other side.

Mark your pulley again, and TDC will be the midpoint between the 2 
marks. 

> My car runs best and most smooth just before that 1st of 4 (total) marks,
> about 10¼ BTDC. At top dead center my car backfires, spits and bogs down. Is
> that timing acceptable or will I burn up!
> 
> The big question is where is my TDC according to "The Dumb Ass Test"

The 4 marks look like:  |   |||   They should mark TDC and 7.5,10 and 
12.5 deg BTDC. It sounds like you have found TDC to be at or near the 
the right hand mark, so your pulley is ~12.5 deg off. Before you 
decide this is the case make sure of your results as I explained 
above.

It is difficult to be very accurate with the moving probe method, but 
the fixed (spark plug) probe should give pretty good results. Still, 
either method should be good enough to verify whether your pulley is 
rotated.

I'm sorry that you had this trouble, but I don't think things are as 
bad as you probably feel right now. In the end it looks like this was 
an important thing for you to do since it appears that there may well 
be a problem with the pulley position.

-
*******************************
Jim Adney, jadney@vwtype3.org
Madison, Wisconsin, USA
*******************************

-------------------------------------------------------------------
Search old messages on the Web!  Visit http://www.vwtype3.org/list/


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]