jakej78b
Veteran Member
I've recently obtained a 2000 Volkswagen Jetta with the ALH engine and 5spd transmission. It has 230k and I've determined in another thread that likely a valve has met a piston sometime in its past. This of course means that the head should come off which will necessitate having to do timing belt work, which I had intended to do anyways since the timing belt history is unknown on this new to me car.
I've got another engine from a car that had about 255k on it and it had a terminally low oil pressure problem, of which the cause was never determined. The car ran great though, it was involved in an accident which is why it has now become my parts car. I got a new turbo, got a new oil pump, oil pressure sensor was replaced. Oil pressure was measured with a mechanical gauge to be around 70PSI at idle while cold, then the pressure dropped as the engine warmed up to around 7-15PSI, depending on engine load and RPM. The best guess was that it needed new crack and/or rod bearings. The real question with this: Is it likely that low oil pressure would be caused by the head, or hard to know? I'd like to swap this head into my car to have to avoid reworking the head completely. If I run under the assumptions that the low oil pressure environment didn't damage the head and that the head was itself not the cause of the low oil pressure then I should have a perfectly good head waiting to be swapped on my car, no? If it helps, I have pictures of some of the cam caps and of the cam on the head in question.
Now, the timing questions:
A lot of the reading I have done suggests to pop the cam sprocket and loosen the injector pump sprocket when performing a timing belt job. I am wondering why one would do this? Couldn't you just lock the cam, crank, and pump then put the new belt on? The procedures also goes on to show timing the pump again as the last step. I could see fine-tuning it maybe but theoretically if you had perfect timing before, you should have perfect timing after assuming nothing moves. I would assume nothing moves since they are locked, therefore locking their sprockets as well (unless you pop them).
What specialty tools do you REALLY need? Near as I can figure I would only need the cam locking tool, the IP can be locked with a perfect fitting drillbit (of which I have many sizes) and I figure the crank doesn't really need to be locked, as long as I frequently verify that it is still in position by visually verifying the flywheel mark... right? If popping the cam sprocket is necessary I've read that this can be done with a gear puller, no? I don't want to save a few dollars and potentially botch the job, but I also don't want to unnecessarily spend if I don't have to. I have a generic adjustable pin wrench that I think would work for counterholding the cam sprocket assuming it needed to be broken lose to begin with and I have many other tools that could perhaps substitute, though no others come to mind for substitute timing tools.
Looking forward to your replies,
Jake
I've got another engine from a car that had about 255k on it and it had a terminally low oil pressure problem, of which the cause was never determined. The car ran great though, it was involved in an accident which is why it has now become my parts car. I got a new turbo, got a new oil pump, oil pressure sensor was replaced. Oil pressure was measured with a mechanical gauge to be around 70PSI at idle while cold, then the pressure dropped as the engine warmed up to around 7-15PSI, depending on engine load and RPM. The best guess was that it needed new crack and/or rod bearings. The real question with this: Is it likely that low oil pressure would be caused by the head, or hard to know? I'd like to swap this head into my car to have to avoid reworking the head completely. If I run under the assumptions that the low oil pressure environment didn't damage the head and that the head was itself not the cause of the low oil pressure then I should have a perfectly good head waiting to be swapped on my car, no? If it helps, I have pictures of some of the cam caps and of the cam on the head in question.
Now, the timing questions:
A lot of the reading I have done suggests to pop the cam sprocket and loosen the injector pump sprocket when performing a timing belt job. I am wondering why one would do this? Couldn't you just lock the cam, crank, and pump then put the new belt on? The procedures also goes on to show timing the pump again as the last step. I could see fine-tuning it maybe but theoretically if you had perfect timing before, you should have perfect timing after assuming nothing moves. I would assume nothing moves since they are locked, therefore locking their sprockets as well (unless you pop them).
What specialty tools do you REALLY need? Near as I can figure I would only need the cam locking tool, the IP can be locked with a perfect fitting drillbit (of which I have many sizes) and I figure the crank doesn't really need to be locked, as long as I frequently verify that it is still in position by visually verifying the flywheel mark... right? If popping the cam sprocket is necessary I've read that this can be done with a gear puller, no? I don't want to save a few dollars and potentially botch the job, but I also don't want to unnecessarily spend if I don't have to. I have a generic adjustable pin wrench that I think would work for counterholding the cam sprocket assuming it needed to be broken lose to begin with and I have many other tools that could perhaps substitute, though no others come to mind for substitute timing tools.
Looking forward to your replies,
Jake