No oil pressure

[Homer T. Coyote]

I have been reading this forum since I bought a TD Jetta about 3 weeks ago. I read w/ great interest "Hagar's Memoirs" (The 58 page thread). Anyway on to my question. When I bought the car I was told it had low oil pressure and I would probably have to replace the main bearings. I changed the bearings which the #2 and 3 bearings had definitely been run w/o oil as they were pitted and missing some babbit. The crank wasn't gouged as the bearings had not spun so it cleaned up nicely and plastiguaged at .002 w/ standard bearings. I also installed a new oil pump. The rod bearings looked okay but I wish I had installed new ones while I have the pan off. After installing a mechanical gauge to be sure, I still have low oil pressure. When cold it reads about 30 to 35 psi but as it warms up it goes down to 5 or so psi and the oil pressure warning buzzer goes off. Any ideas?


P.S. Was that your American Idol tryout Andrew?

[libbybapa]

Nope, no tryout, just having a little fun.

Anyway, with regard to oil pressure, by far the most likely culprit on these motors is the intermediate shaft bearings. They tend to flake away and disintegrate, especially when the timing belt is over-tightened. It might be possible to replace them in a jetta with the engine still in the car, but I have never done so myself. some special tools are required for removing and replacing them as they are circular bearings that are pressed into the block with an interference fit. Some care must also be taken to ensure that they go in correctly oriented, especially the rear one which has a channel to direct a stream of oil onto the vac pump drive gear.

Andrew

[VanagonMark]

If the intermediate bearing is the same one on the 1.6, I know a guy who
sells those bearing new

[libbybapa]

Most friendly local auto parts stores will have the pre-sized std intermediate shaft bearings on hand for less than $20. There's a thread kicking around on this site or the GTD forum that outlines all the interchange numbers for the various US bearing makers.

Andrew

[tylernt]

I've read that the intermediate shaft bearings can be replaced by undoing a couple of motor mounts, lowering the engine as far as you can, and then cutting a notch in your body to allow the removal of the shaft. I wonder if you could slide the shaft out just enough to change just the drivers side bearing without notching the body? Of course, that's probably pointless if it's usually the passenger side that causes the low oil pressure.

Don't new bearings need to be reamed prior to reinstalling the int. shaft? Or do they all come pre-reamed these days?

[libbybapa]

You can get them either way, but unless the shaft is messed up and needs turning, I don't see a reason for the oversize ones that need to be reamed in place. I don't see how you would be able to change either bearing without the shaft completely removed. You need to use some kind of pusher or puller to put the bearings into place and as I see it the tool would need to be where the shaft normally is. I don't see a way around it.

Andrew

[Homer T. Coyote]

Thanks for the info although it is not what I wanted to hear. I'll get started on pulling the engine out. Would it be easier to come out the top or bottom. I have access to a lift if it would be easier to remove it from the bottom.

[tylernt]

You don't say what year it is, but '84 and older come out the bottom. You can also remove the trans beforehand, or, remove it together with the engine as a unit if convenient.

Not sure about '85 and newer.

[Homer T. Coyote]

It is an '85.

[Fatmobile]

On an '85; remove the radiator and support, then lift it up and pull it out the front..

[hagar]

When cold it reads about 30 to 35 psi but as it warms up it goes down to 5 or so psi and the oil pressure warning buzzer goes off. Any ideas?

N.C --1985 Jetta. ----does hagar ? ---yes , YES .and one more yes.
First RELAX go driving and then have a --a glass of your choice ---turn on the HI -FI and play --Nothing could be finer than to be in Carolina , with a Turbo Jetta in the morning----and then read.

When Fraulein Bunny Bondo snared hagar on 05 Mar 2003 ---251.827.7 on clock ---she had lower pressures than your 1985.----for 500 dollars Kanadian ---hagar "Who Me Worry ?" ---- today in 2007 and ---266.900 on clock --we still go skylarking. ----You must install the BIG oilpump on those --VW 1.6L Turbo diesel engines.----did you ?. the top end needs only about 1 or 2 PSIG to be happy at idle.---

SO ? RELAX ----in this forum and Dan's ---as a Newbie --IMHO --you hit the Jack--Pot.

hagar.

[Homer T. Coyote]

I was hoping the Hillbilly Tuner would throw in his 2 cents. I bought what the import parts place gave me. It was a Schadek. I did have to install shorter pump bolts as the replacement wasn't as tall as the stock. Did I get a bum steer?

[tylernt]

There are several different sizes of oil pump gears. 27mm, 30mm, and 36mm. If you got smaller gears, then at could certainly cause a low oil pressure situation. The bigger pumps take longer bolts, so if you had to use shorter bolts, I think you got a downgraded oil pump!

What weight of oil are you running? Most people seem to recommend oil heavier than the common 10W30. I run 10W40 myself.

[VanagonMark]

There are several different sizes of oil pump gears. 27mm, 30mm, and 36mm. If you got smaller gears, then at could certainly cause a low oil pressure situation. The bigger pumps take longer bolts, so if you had to use shorter bolts, I think you got a downgraded oil pump!

What weight of oil are you running? Most people seem to recommend oil heavier than the common 10W30. I run 10W40 myself.

I'm a 20/50 fan myself
Walmart stuff
made by Quaker State

[Homer T. Coyote]

And I also found the pump at The Parts Bin $40 cheaper. Just damn. Live diesels and learn I guess. I put the Mobil Delvac 15-40 from Walmart to break it in as it was supposed to have new rings. I will use a diesel synthetic after that although its hard to find reasonably priced. I actually think that supertech stuff at Walmart would do fine. It has to meet all of the API specs, right?