IP "screw on the front" what?

[hvguy]

I asked a guy on youtube what he did to his pump and he replied that he turned up the screw on the front of the pump.... since I only saw 1 screw on the front of the pump that looked like it did anything-it had this little stainless sleeve spot-welded onto the screw to prevent you from cranking it too far in...

After cutting the sleeve off and turning it in about... 4 turns I proceeded to turn the engine on O_o it went WAAAAAAAY high revs and since the key wouldnt turn off the pump for some reason I quickly snuffed the intake with my hand, whew, wtf just happened?

after returning the screw to its somewhat OEM position, I cranked the engine and got it to idle, backed the screw out almost where it would kill the engine... it was smoking black at that time, so I turned in the screw and it proceeded to idle up, so I backed the idle down on the "throttle lever" to where it would idle better.... it seemed with this screw turned in about 1 turn it was waaaaay more responsive...

so what is this screw doing?

[hvguy]

btw here is what he said in his msg:
i just turned screw to the maximum in front of the injection pump.

here is the video i was asking about
http://www.youtube.com/watch?v=GesuengHytw

[Jason]

Wow you came close to blowing your engine up, and your lucky the turbo didn't hurt your hand in some way, try that on a bigger engine and you will loose your hand. Did you read the sticky in the performance section about adjusting the injection pump? I wrote a whole section just about run away, which is what you had happen. You never adjust the main fuel screw in without the engine running. I also detailed the various injection pump adjustments that can be made to get more fuel. Do some more reading before you atempt any more adjustments. There is a pretty big knowledge base here, I think you will have better luck asking questions here than on youtube!

Jason

[hvguy]

thankfully the turbo is still in the "building the manifold" stage, so I just plugged my hand over the intake..

Im aware of what a runaway diesel it :p Ive seen quite a few of em caused by blown turbo seals... but never from the pump.

Ill dig around a bit more, sorry for not searching, I should have known better.:(