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no oil pressure

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Old 11-14-2013, 08:02 AM
  #46  
FRporscheman
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I was mistaken on this pickup tube seal not working. It's a late seal and an early engine, but it works fine. The first time I tried it, I just held it in place and thought it looked small. Now I actually installed it, and it felt great.

I also installed a used, known-good oil pump. I cleaned it first (careful not to get the oil out of the gears) and used loctite 574. I'll prime it just to be safe.

Once I get the timing belt (et al) back on, but before putting the crossmember back on, I'll try fast cranking with some lighter oil to see if it will build pressure. I might try warming up the oil first.
Old 11-14-2013, 01:48 PM
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harveyf
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Sounds like a plan.

The Reinz seal kits are a little disconcerting, as there are more seals and gaskets than you need and you have to use a little educated guesswork to pick out the appropriate ones for your particular engine. I'm sure the one size fits all kit approach reduces the overall cost.

The "lip" type seals that go around rotating shafts are easy, as you can match up the size code from the PET with that stamped on the seal. But the generic round rubber donuts can be pretty confusing.
Old 11-15-2013, 02:56 AM
  #48  
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It helps if you can save the old seals/o-rings and label them, so you can find the matching new pieces and install them.
Old 11-16-2013, 07:02 AM
  #49  
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I got the belts back on, poured in 4 quarts of 5w-20, took off the oil filter, and fast cranked. Still no oil coming to the filter.

How long should I be cranking? I tried 15 second intervals, with about a minute between to cool off the starter.

My brother was cranking while I was watching the filter stand. He said that while cranking, the pressure would go up to about 1.5 (it's at 0.5 when not cranking)... but the filter was off and no oil was getting to there. So I don't know if I can trust that gauge, but I still want to see some oil get to the filter.
Old 11-16-2013, 08:40 AM
  #50  
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I recently restarted my Turbo after 6 months. I had drained the oil at the time I took the car off the road. Anyway, 6 months later, new turbo fitted ect and ready to start. I added 6 litres of oil and new filter. I could not build any pressure with sparkplugs removed ect after several prolonged attempts. In the end I started the car in short 5 sec. bursts and after several minutes I got full 4.5bar cold pressure settling to 3bar hot as per usual. I think you may be being a bit cautious to be honest...
Old 11-16-2013, 08:59 AM
  #51  
Eric_Oz_S2
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Just did the same. It probably took about 8 x 15sec bursts to get oil pressure with plugs removed.
Old 11-17-2013, 08:37 AM
  #52  
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I primed the new pump by pouring oil down the side hole in the oil filter stand, while turning the crank CCW (which did pull the oil in).

I did 3 runs of 30 seconds of cranking, followed by 3 runs of 15 seconds. No oil came up to the oil filter except for the oil I poured in there to prime it. It just won't pick up any oil from the pan.

I even took off the OPRV again to see if oil spilled out from there during cranking, and it didn't.

I decided, F it, I wanted to start the engine and let it idle. Well, now the engine doesn't start, I can't figure out why. It started before, and nothing's changed!

F this damned engine, I'm giving up on it. I'll see if I can return it. There must be a leak in the girdle, and I'm sure not going to rebuild this thing!
Old 11-18-2013, 07:45 PM
  #53  
txhokie4life
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Are you sure the new oil pump is from the right year.

The early ones are different from the later ones and
you can only tell by looking at the mating surfaces -- they are identical from the outside.

don't ask me how I know :-(

mike
Old 11-18-2013, 07:51 PM
  #54  
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You didn't say you changed oil pumps... Not only do they have different mating surfaces, but the gear sets are different sizes and not interchangeable (well, an early gear set will *fit* in a late pump, but it won't make suction - don't ask me how I know, either!).
Old 11-21-2013, 11:20 AM
  #55  
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I would try to get it started. Plugs in the right firing order? DME relay in good?
Old 11-21-2013, 11:41 AM
  #56  
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If you know there's no oil pressure, don't start it. That's only going to add certain harm to an already existing problem.

Can you tell us again the exact history of the engine and what has/hasn't been done?
Old 11-21-2013, 01:13 PM
  #57  
kev951
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Arash, dumb question but, have you had the fuel system hooked up the whole time you have been doing testing? You may have possibly washed the piston rings with fuel, and now you have no compression due to fuel in the rings and bores. Lack of compression can cause some oil pressure issues. IF this is the case, you need to prime the rings by dumping oil in each spark plug hole and turn the engine over .. Only if this is the case.

Last edited by kev951; 11-21-2013 at 02:20 PM.
Old 11-23-2013, 06:21 PM
  #58  
Charlie
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If you search my posting years ago you will see where I went through the same on a car that I bought. I tried a new oil pump, priming, pick up tube and the problem OPRV not making a good seal. Try a different one and see if that doesn't solve the problem. If the OPRV valve has a small air leak the pump cannot pull oil. I had a one piece valve and the piston was not quite returning to the top and letting air through the passage. Try a known good one piece valve and see if that doesn't solve the problem.

Also be sure it is the correct OPRV for the engine.
Old 11-23-2013, 08:23 PM
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951and944S
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Originally Posted by kev951
Arash, dumb question but, have you had the fuel system hooked up the whole time you have been doing testing? You may have possibly washed the piston rings with fuel, and now you have no compression due to fuel in the rings and bores. Lack of compression can cause some oil pressure issues. IF this is the case, you need to prime the rings by dumping oil in each spark plug hole and turn the engine over .. Only if this is the case.
Huh....?

T
Old 11-23-2013, 08:27 PM
  #60  
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Originally Posted by Charlie
Try a different one and see if that doesn't solve the problem. If the OPRV valve has a small air leak the pump cannot pull oil. I had a one piece valve and the piston was not quite returning to the top and letting air through the passage. Try a known good one piece valve and see if that doesn't solve the problem.

Also be sure it is the correct OPRV for the engine.


As an extra precaution, I'd disassemble the original pump that was obviously functioning when the car was wrecked, check it and go back with that one.

The problem could have been the OPR the whole time and now he's gone and put an unknown pump in the equation.

T



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