Advancing Pump Timing - quick n dirty?

[rs899]

OK- I have the formerly trashed 91 Jetta running reasonably well now, but I am sure the IP timing is retarded because it runs sluglike compared to my Caddy and when I pull the cold start it picks right up and sounds nice.

So, I tried to advance it, but the IP has run out of room towards the block.

I need to advance the pump by one tooth, then go from there.  I think this means  holding the belt in its current position, then rotating the pump clockwise one tooth, correct?

How do you guys do such a thing without upsetting cam and crank timing?

Rick

[theman53]

I don't believe that you can. Best would be to retime with the dial indicator. Unless someone else knows better.

[Rabbit on Roids]

i would advise AGAINST doing what you said. if you do one whole tooth, you probably wont be able to retard it enough to run right.

[rs899]

Ok, technique aside, for the time being.  There has to be a way for this thing to run with the "proper" advance.  I used a dial indicator on it and it's right around 1mm right now, but it obviously needs more advance.  Maybe I didn't read it right ?( I have done it countless times, but never on this car).

What's wrong with advancing a tooth and then pulling the pump towards me?

[dennis]

Might want to check internal pump pressure.

[rs899]

Thanks Andrew-

In fooling around for 16 years with my Caddy, I never have had to deviate from using the dial indicator reading as gospel.  But this time with this Jetta, I am going to have to do more of a seat of the pants setting to get it running better.

I am a little nervous doing it this way, but am I correct in thinking that as long as my cam and crank are dead on with each other, having timing a tooth off one way or the other (until I dial it in by feel) will not damage anything?

Rick

[rs899]

OK, so thinking ahead, if I fudge it this way and get it to run better, I presume I will end up with more lift than the book says I should have, but what?

That complicates my future timing belt changes ( if I use the same IP).  I guess I will need to eventually record what the dial indicator "sweet spot" reading is for this pump. Any better ideas?

Rick

[Vincent Waldon]

I guess I will need to eventually record what the dial indicator "sweet spot" reading is for this pump. Any better ideas?

I think that's a very reasonable approach.  The dial indicator method doesn't account for cam wear, injector pressures etc,  so sometimes needs a bit of tweaking... but its advantage is that it's reproducable.  If you manually find where your engine runs best and then measure it you'll have dialed in your specific pump/injectors/etc in a reproducible way.

[rs899]

It occurs to me that I just need to remember to record the lift with the dial indicator on the old belt when I go to change it 3-4 years from now.  Now, the problem is trying to figure a fail-safe way to do that- perhaps a yellow sticky in the Bentley?  Except that having done this so often, I may not even look at the Bentley....getting old sucks.

Rick

[Rabbit on Roids]

write it on the wall of your shop. thats where i write stuff that i dont wanna lose.

[8v-of-fury]

write it on the wall of your shop. thats where i write stuff that i dont wanna lose.

I keep a notebook in my tool box I'm only 20.. but i still have a memory like sieve sometimes lol

[rs899]

Maybe I'll put a note on the strut tower.  If I use a permanent marker, though, it might eventually fade due to diesel and solvents- probably have to use paint.

[ein bora]

The flywheel on my 1.9 IDI has two TDC marks, apparently the same flywheel is used on some gassers so the second mark is 6 degrees BTDC. When I first set the timing up of coarse I had the wrong TDC. The car ran but I had to run the pump all the way up to advance it as far as I could - and had issues like you described. When I finally figured it out, now it sits where it should and runs as it should. Not saying you have the same issue, but maybe worth checking out.

[rs899]

I think my flywheel is OK, since I had the head off a few weeks ago and it looked like TDC was where I expected it (but I know the gasser flywheel you are talking about and I agree it is confusing).  I slipped the IP one cog advanced and now it runs better- and I used up almost that whole cog.  I haven't measured it with a dial indicator- I am curious to find out what it is.

[Rabbit on Roids]

i had that problem too, as i used a gasser flywheel, and it had only gasser timing marks.