main bearing clearance

[turbosuzi]

There is a hole but with thetype of union that is there I dont see how it would send my oil psi down so far. I think that it must get oil up into the vac mechanism seals, otherwise I dont know how oil would get up there. I will try another pump I have and let you know what happens.
Im still wondering if the oil pump shaft beaing might have anything to do with oil pressure?

[Rabbit on Roids]

no no no, the oil pump shaft doesnt lube the gear. it lubes the inside of the vacuum pump. you remember on the ancient 1.5's how they had an oil tube from the filter flange to the vac pump? the hole in the center of the oil pump shaft replaced that design. they may have eliminated that design when they went to the vane pump tho. but the pump from my MF 1.6 had a hole in the shaft, and a vane pump. 

[turbosuzi]

So I should look at replacing the shaft seal and the bearing? The bearing being an oil supplier to the shaft was never replaced and the motor was siezed a couple of years ago, and ran hot and high rpm a couple of weeks ago. The bearing could be non-existant.
Any tips on replacing the sahft bearing?

[Rabbit on Roids]

no no no, the oil pump shaft doesnt lube the gear. it lubes the inside of the vacuum pump.

Are you saying "no no no" to my post?  That's what I just said, the oil pump shaft sends oil up into the vac pump.  The jet from the intermediate shaft bearing lubes the vac pump / intermediate shaft gears.

Andrew

no, im not saying that to you. i was just saying that the IM bearing doesnt lube the INSIDE WORKINGS of the pump. i know that it lubes the pump and shaft gears, but the hole in the shaft is for the insides. i was not aware that theres a little seal in the bottom of the gear either.

[turbosuzi]

replaced the vac pump with one that had a better seal and was not chewed up in side the gear and still the same.I get over 25 psi then it goes down to 1-3psi after about 5 min of idle. What is next the for the low oil psi saga? If bottom end is tight, IM bearings are tight, oil pump is working good, vac pump seal is good, oil jets are new, then where is the oil going? What should I look for in the head?

[turbosuzi]

can I use pliasti gauge on the cam bearings and what is the spec for them?
I didn't see if the bushing was in good shape or not but I will get one from the stealership tomorrow, I don't want to take any chances with this thing.

[rallydiesel]

There are no cam bearings.

[rallydiesel]

When you got the vac pump out did you look at the oil pump shaft bushing?  To replace it, you need to pull the pan, pull the oil pump (I'm sure by now you're good at that...   ).  Then use a socket on an extension to tap the bushing out.  I flip the appropriately sized socket around on the extension so the flat part of the socket is against the bushing when tapping it in to avoid marring the top surface.

You could have an assistant drive the oil pump using an electric drill and have the valve cover and oil pan off in order to see where it's gushing.  Be prepared to get very oil soaked...

 

Do you know a part number for that bushing? You think that would affect oil pressure that much?

[Rabbit on Roids]

the oil pump shaft bushing wont really affect it that much, but the seal in the bottom of the vac pump gear that andrew mentioned can cause problems.

[turbosuzi]

I am in town today and is my only day to get parts. Is there any thing else that you can think of that I might get other than the oil pump shaft bushing and another pan gasket? By the way I pinched the line to the turbo wile running to see if that was the culprit in my low oil pressure and it didn't make any difference in hot oil pressure. My engine has silicone transmission cooler lines running to the front of the rad through a transmission cooler to the turbo. I could see some of you cringing at the thought of some one pinching the turbo line to check for oil pressure loss.
Thanks for all of your help guys.

[Rabbit on Roids]

Yes, it could certainly affect it that much.  If oil flow were unrestricted from that galley, hot oil pressure would be zero.  The seal in the bottom of the vac pump would have much less effect as the diameter of the channel in the shaft is much smaller than the feed hole of the shaft bushing.  056 103 541 is the part #.

see, i thought you meant it the other way around. sorry for the mis-information.

[Rabbit on Roids]

use waste motor oil. then you wont be wasting anything! lol

[turbosuzi]

I ordered the bushing from the stealership today, to my suprise it was only $12.00. I wont get it until Thurs and hopefully installed on sat. I will let you know what happens.

[turbosuzi]

I replaced the bushing today and still the same condtion, 25+psi at start up then after about 10min of idle oil pressure goes down to 1-2 psi. What next? Is there anything in the head that could be loosing that much oil psi? This is my daily driver and I am really afraid to drive it.

[rallydiesel]

Did you plastigauge the rod bearings as well?