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I've read a bunch of threads about having no oil pressure and I can't really say I've seen not having the seal on the RETURN tube being an issue. Usually the problem is either with the OPRV, the torque on the crank pulley being off, the sleeve missing or backwards on the crank that activates the oil pump, or a missing o-ring on the oil pickup tube.
Hopefully someone with more experience on the return tube will chime in.
Yeah I've read that too. But there's obviously a seal on the return tube for a reason, so I'll at least have that fixed and can rule that out. I'll also have an OEM rather than a Victor Reinz Seal on my oil pickup tube.
I know my OPRV is fine, since my special tool slides in with no resistance at all, and I can thread in the oprv by hand up until I have to tighten it.
I also know that I have my oil drive gear in, with the washer, and have twice verified my torque on the bolt, even going up to 160 ft lbs.
I'm anxious to get this fixed, and I feel like I'm almost there. I'm just glad that I don't care about the Super Bowl so I can get this done today, lol.
Well my pickup tube doesn't leak any water when I fill it up and block off the tube, so it's not cracked.
I'm about to replace the pickup tube seal and the return tube o ring and get things reinstalled. I'll keep you guys posted.
Well, I reinstalled everything, and I'm still at 1-2 bar on my gauge.
Originally I put 5W-20 STP oil in by mistake, and the car settled at around 2 bar. Once I drained that and put the proper 20W-50 in (STP brand), the car settles between 1-1.5 bar.
This is getting incredibly irritating I'm I'm ready to just set the whole thing on fire.
As a recap for anyone coming into this later:
Rebuilt the whole engine and replaced the crank and associated connecting rod due to a spun rod bearing.
Reinstalled, had a failed oil pressure sender (pegged at 5 bar) during the first start up.
Replaced sender, now I'm seeing between 1-2 bar, usually on the lower end at idle. Definite clacking at the cam tower. Giving the engine gas, I can get the pressure up to 4 bar.
Suspected the OPRV being misaligned, ordered alignment tool for the early one piece OPRV, reinstalled, same result.
Checked the OPRV for binding, both components move smoothly. Green o ring was replaced during rebuild.
Doubled checked the crank nose bolt torque. Tightened currently to 155 ft-lbs, probably a little higher. The conical washer is facing the correct direction.
I'm nearly certain that I replaced the washer between the belt gear and drive gear, and it's not lying around my relatively well organized garage. But at this point I'm doubting everything., especially since I can't readily see it with the plastic shroud on.
Pulled the oil pan back off, suspecting a bad pickup tube or seal. Tube is fine (filled it with water, stopped off one end, no leaks), clear/translucent victor reinz seal was installed, but I went ahead and replaced it with a black one from 944online. The return tube did not have a seal, so I installed one from 944online.
No improvement.
At this point, I'm left with the oil pump being bad (though it seems to somewhat function given I've gotten pressure up to 4 bar), somehow missing the washer in front of the drive gear, or possibly the power steering pulley being misaligned. I really do not think that my STP oil filter is an issue, but I'm questioning everything now.
Well, after testing a known good OPRV, I have found that my issues aren't that. So it's isolated to my pump region. After pulling off my best covers, I noticed that I had installed my timing belt crank gear backwards. I'm guessing this is the source of my woes?
I'm 99% certain that I installed the green o-ring and the washer before I installed the timing gear. I don't have those parts on my bench nor in my rebuild kit bags, and I have the old o-ring out (I save all of my old components so I know what I replaced).
I definitely installed the timing gear backwards though (I looked through my assembly pictures and it's definitely on wrong), so that needs fixed no matter what, and it kind of is the Occam's razor thought at the moment of what's wrong, especially since I ruled out the oil pickup tube, oil cooler alignment, OPRV, oil weight, crank bolt torque, and there aren't leaks.
I'm guessing that the gear's flange is putting improper pressure (or none depending on the diameter differences) on that washer. It's somewhat logical, especially since I've ruled nearly everything else out.
I thought about the PS pulley, but I'm also 99% certain it's on straight. Though If I were to remove , I'm guessing I'd need a spacer of the same thickness to test it out.
As for a mechanical gauge, that's the only variable I haven't ruled out, mostly because I had a very hard time justifying a $34 + shipping adapter to use on a $20 gauge. Though the cam noise verifies that I'm not receiving sufficient oil pressure in my opinion.
I managed to find another 944 enthusiast (and helicopter mechanic) local to me who is going to help me reinstall my belts with the correct tools.
If all of this fails, I'm likely going to have to go with getting a new pump, which I won't be looking forward to.
i think i chimed in on another thread of yours but in my experience the engine absolutely will not turn over with the gear on backwards.
i guess there may be different tolerances and there were a few different versions of the gear over the years.
no need for a spacer to make up for the PS pulley, the crank threads are deep enough. i ran for years with my PS pulley just removed (PS disabled).
I plan on working on it today, since I managed to borrow a flywheel lock, so I'll try it out.
Forgive my ignorance, but how would turning the gear backward cause the crank to bind? I'm guessing it clamps against the pump, but that only seems possible if the inner diameter and thickness of the gear flange is greater than that of the drive gear washer. Looking at a few pics online, it seems like the diameter is smaller, but I can't vouch for the thickness. All I know is that the gear is on backwards and it spins (can't feel the flange against the balance shaft gear, can visually see the shoulder, and I have prior pictures before assembling that has the gear backwards, can hand rotate the crank with a socket and wrench).
I'll update when I get it figured out.
when i've done it, once the bolt is torqued down it is impossible to turn the crank with an 18" breaker bar - the flange somehow jams against the oil pump.
Got the gear off. Definitely was backwards. The PS pulley looked like it was one centered with no unusual wear.
Looks like the plastic belt protector has been acting as a low friction surface for my gear, which explains why it was able to spin despite being torqued down. You can see some of the plastic on the scribed numbering on the gear flange too.
I'm going to get this mostly assembled back.
I figured that, since I'm at this point, I'm going to install a 4 degree cam key to bring the torque curve lower in my rpms
02-04-2018, 04:15 PM
