this may apply to mars' topic as well.
(below).
The only reason you would have to do that is if you are doing it incorrectly.
i totally do not agree. i have a situation as it is in two cars, both mk3s.
if you set up TB correctly, and in doing so the IP at the 'pin' point, it/mine never start. they will chug over and not start.
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my method of 'new' TB w/advancing inj pump one tooth. having some help from other members for this. and thanks to the members who helped. this works(for me).
as a note when you are ready to tension belt, you want to pull the pump timing pin.
crank and cam line up, lock (and feelers)in cam. pin in pump. tensioner fully un-tensioned. the small idler pulley *not on*. put belt on, using white out mark an inj pump pulley tooth and the belt where the tooth fits. (doing this will guarantee you know you move the pump -*one tooth*-.)
put a wrench on pump pulley nut. if you pull pin, with tension all the way in slack, and the small idler removed, you should have enough slackness in the belt to move (say)the pump as you want. we want -*one tooth*-advance.
shouldnt be hard to do, you may need a second pair of hands, that can help, yet not get in the way, too much.
when you do this, check the crank is still on TDC, if not you will have to figure how you want to go about it so its correct. <here.
if all is correct, how you want it. put idler pulley in. tensioner can now be done. again, now, check crank is at TDC, cam should still be locked.
continue; finish timing procedure.
hope this helps, it should.
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if this is the case, you need to advance pump the one tooth, and some of us do.
some notes to get correct. going all the way to the top of my 'method'; where the timing belt is removed. (belt will be off, crank and cam line up. go from here).
we want to set the pump, if you advance the pump the one tooth, you will have to set the pump. it needs to be *retarded* to 'line up' correctly.
with inj lines removed, you loosen all 4 pump body(timing) bolts(2 are nuts). (i when doing TB job, will now remove the bottom pump bolt, so when electronically timing it you wont lose it). turn the pump full retard, i now bump the pump up some, not very much. retard is moving the pump 'away' from the motor. i now tighten the pump bolt nearest the front of the car.
pin the pump, and start where i have the crank/cam lined up and pump pinned.