93 golf IDI bosch fuel pump timing spec

[jari_veedub]

I tried to search but no luck.  I am replacing my fuel pump because it leaked at the main shaft.  I have the dial indicator tool that screws into the end of the pump when setting the timing.  I don't have the spec on how many thou when at tdc, the inj pump plunger should be at.  Is it 0.090 +/- 0.02  ??

Thanks in advance.

[bigblockchev]

From my Bentley manual it says .80 mm +/- .02 for adjustment and .73 - .87 mm for checking. I think many of us are increasing that value at our discretion to the .09 - 1.0 mm range. these are all in mm not thousandths so be careful.  Cheers Dan

[jari_veedub]

Thx,
My buddy has my manual and I can't get a hold of him.  You actually meant 0.9 mm which is a typo.... no problem.  Converted to inches which is my gauge units , I was able to set the pump  0.035".
However, when I start the engine up, the engine races away.  Tough trying to figure this out without a manual.  My wife is working out of town and has our other car, so I am stuck at my home/shop and don't have wheels to get into town.  :)

The pump I just installed is identical to my previous pump in regards to where all the screws are set at.
Any idea... ?

[bigblockchev]

By racing do you mean that the engine goes to 5000 rpm immediatley or is it more like 1500. Trying to get an idea of the scope of the problem. What is the condition and history of the newer pump, is it rebuilt, did it run correctly on the other car. Does the cold start advance cable work or is it permanently stuck on. Are the cables too tight. Has the max fuel screw been adjusted, is the locknut still tight or has it been loosened off to increase power. Did you rotate the engine two turns before taking the dial reading in case something was sticking. Is the pump identical to the original. Give us some background on the vehicle Kms ,ownership repair history, I'm sure someone has experienced a similar problem and been able to solve it. I'm a relative noob but there are many knowledgeable people out there. Cheers Dan

[jari_veedub]

Just to follow up on this post, see my other post on this topic.

The engine as soon as it started jumped to 5000 rpm within seconds.  I brought the pump back to the scrap yard and got another pump.  I don't know the history of the 1st pump, but the one I got in exchanged works.  I've put over 75 km since I replaced the pump and it works good so far.