QuestionNeed some advice on aligning timing marks on a 1990 VW Jetta.
AnswerI am assuming that you are replacing the timing belt and decided you could do this without reading an instruction manual first…not a good thing, for even the mechanics glance it over to make life easier.
If you can go to the library and borrow a book, pics help alot, my choice publication from Haynes then clymer
I can only relate to the cars I have done which are 4 cylinder diesels. So you will have to fill in the blank spots or ignore what is not relavant
I have a single cam so I can only refer to it for timing description but you should be able to follow and compare.
We first have to set your engine to #1 position. To do that the piston needs to be set to the top of the compression stroke. This is done by first removing the plastic cover(unscrew the whole 2” plastic cap from the top of the transmission near the bellhousing). In this way you can see the flywheel, and if you look on the under-ledge of the cap hole, you will see a small pointer(get a light in there to see). Rotate the motor by hand until you see a “V” groove mark on the flywheel…that will be the No 1 piston, align it with the pointer..
Anyways, with the cam is exposed, rotate the motor via a socket wrench on the pulley center nut until you see a line on the inside edge of the cam pulley approach 12 o'clock position. Stop there. Now, go to your fuel injection pump and look on its pulley on the inside closest to the pump for a mark and something corresponding to that mark on the pump itself. You should be there. Did you notice the slot in the cam end near #4 cylinder? Do you have the stock wrench that comes with every VW made...that wrench will slip in that slot and rest on both sides of the head locking the cam from rotating. You are there if it does so (that slot is cut off centre for a reason) otherwise you gotta rotate the engine again as you are not on compression stroke for #1(((and if the timing belt is not on you gotta work it like the belt is on or you will hit valves---otherwise pull the head and visually set #1 piston to TDC and set the head so that the valves are closed on #1---. Again another check is look at the cam lobes over #1 - the pointed ends of the lobes should be pointing into the air(in my diesel like a victory "V")
Now that I am in #1 I must also lock the injector pump from turning and that is done by sticking in a 13mm socket thru one of the hole in the drive pulley so that it connects to the nut behind the hole. Feel with your finger to find out which hole. The socket (1/2” drive) is just big enough to fill the hole.
Before I forget, lock the engine by putting the transmission into gear.
Where is your distributor in this? No where as it can always be adjusted after you set up the mechanicals.
