Carpokes

I went back and read this entire string to see if anything jumped out as being awry. The first thing I noticed (see your post #18) is there's no black plastic insert in your oil pan. It's there to act as a crank scraper and to direct return oil from the rotating masses back to the oil pickup. If it's not there, you need to pull that pan (I know, ugh) and install it with the proper 6mm bolts. While you have the pan off, carefully inspect the oil pickup tube. They are known to crack at the base closest to the block and will often not allow the oil system to prime (since it's sucking air). If this turns out to be the problem, be glad you found it now. As an aside, if all components are assembled correctly, the 155 ft. lb. torque on the crank bolt is not a big issue. Yes, it needs to be torqued correctly before buttoning everything up, but the torque itself will not affect oil pressure occurring.

Thanks Michael - the insert is in there. I toyed with leaving it out since this is purely a street car, but did put it back in.

Everything with regard to the pickup seemed good and secure (and of course it did work previously). I guess I could have messed it up somehow pulling the pan this last time.

I still think it is something to do with the front crank pulley assembly. This is reminiscent of what happened when I first put everything together and got no pressure - then realized the crank bolt was not pulling against the oil pump gear enough due to the width of the trigger wheel. That is where that extra washer came into play. I must have just gotten REALLY lucky for it to have worked the first time it was installed. That makes it so frustrating now.

I think that power steering pulley has gotten messed up somehow (not lining up as Tom mentioned and I have evidence of). But of course, now it won’t prime with just the balance shaft and alt pulleys installed.

Another thought (I’m a math guy)…

How challenging would it be or advisable even, to try to figure out just what the distances of travel are for these components to see what is going on. It might help folks in the future, but I’m really not sure how to begin the process…

So one reason I bring this up is there is a limitation in the depth on the backside of the large factory washer that goes directly against the PS pulley and the crank bolt has a groove in it that fits around the crank itself. I “believe” that means there is a limit to the range of motion that can be achieved in pulling snug against the oil pump drive.

I am overthinking this I know…

Put some Play-Doh on the bottom of the PS pulley and push it down as far as it will go. The clay should squish out completely, with no measurable thickness left. If it's not getting all the way down, you'll have a layer of clay representing the gap.

Ok two video links follow - Tom that was a great idea. Difficult to achieve but see what you think.

Second video are observations after the experiment and a pic

Video of observations -



Photo with washer in place:

Simply make sure your spacer washer is the same thickness as your trigger wheel.

I can't take credit for the clay idea -- folks have been using it to check clearances since before I was born -- more typically to check piston to valve clearances, etc., but still...

I was thinking your trigger wheel (inner diameter) might be preventing the p/s pulley from nesting all the way in, even if the spacer was the same thickness as the trigger wheel. But if the clay all squished out, that would mean the pulley is bottoming out on your washer and the trigger wheel isn't holding it back.

What exactly have you done to the motor since the last time it had oil pressure? What caused it to loose oil pressure?

Often, when I change my oil filter, it takes maybe 3 or 4 nerve-rattling seconds for the oil pressure to come back when I first start it. Any chance you just haven't cranked enough?

On a separate note, it occurred to me watching those videos that the p/s pulley on the crank is going to be a couple millimeters further forward than the pulley on your p/s pump -- by the thickness of your spacer washer. Hard to say how that will play out, but there's a real chance you'll chew up the p/s belt prematurely if the pulleys are not in the same plane. There are quite a few fully-sorted trigger wheel kits out there worth considering, including several developed by folks who frequent Carpokes -- and at least one by a world-class 944 engine builder who frequents this thread

What exactly have you done to the motor since the last time it had oil pressure? What caused it to loose oil pressure?
Only removed the front pulley setup (left the timing gear in place with belt on) - so loosened torque, slipped pulleys off, replaced rear cover, replaced everything else).

I have done this three times now (taken the front pulley off) in this gut-wrenching process. Each time, it has taken several weeks (months or years) to get the job done, so I assume that the oil just drains off in that long time span. Each time it has taken a large number of stressful tries to get pressure to build.

What is weird about this time is it seems to be taking even longer.

Often, when I change my oil filter, it takes maybe 3 or 4 nerve-rattling seconds for the oil pressure to come back when I first start it. Any chance you just haven't cranked enough?
I am almost worried about the opposite - I have been cranking in about 10-15 second increments (in other words, continuous cranking for 10-15 seconds - stop for a few seconds, wash rinse and repeat). I would do this 4 times or so and then stop to give the starter a rest for 10-15 minutes.

In the meantime, I have tried to reverse prime the oil pump (through the filter) although the last few times I have tried this the oil really just does not go in to the engine...which coupled with the video of oil filter removed and slight oil coming from the pump, I am thinking it is primed and all is fine there.

I have also attempted to do the cranking process while adding air pressure through the dipstick tube.

So...can I draw these conclusions in trying to narrow down where I am at?
1. Based on evidence, the oil pump is primed. If I can't say that, what can I do to get it there and check that box?
2. The problem lies somewhere between the front crank bolt and the oil pump drive gear.

Based on that what next? If the pump is moving "a little" oil - enough to cause it to come up into the oil filter area, it obviously turns some - how do I figure out how it needs to move more? Seems like that is the $64,000 question and obviously one you can't "see" happening.

Well, I suppose after months or years of sitting, it could be just about anything... Stuck OPRV, cracked pick-up (thermal expansion and time), bad oil sender tricking you, just not primed, lack of clamp on the oil sleeve, etc. Although if I am following along correctly, it looks like you had the oil pan off since starting this thread in Nov 23? Not impossible to crack the pick-up tube when reinstalling the pan....

I looked at that video showing it crank without the filter on, and I'd have to think you'd pump a lot more oil out if the pump was picking up oil. If I'm thinking about it right, that would point to lack of priming or not picking up oil, but not a stuck OPRV. I'd be inclined to double down on priming and cranking before pulling everything apart again. Pull the filter and pour oil down both ports, then rotate the motor with the crank bolt in both directions a bit, then pressurize the dip stick tube and crank again (and again) with no plugs. Don't be shy -- sometimes the stars need to align for the pump to prime.

Did you see Gruhsy's last comment in post #32 of this thread. Did you use an oil stone to get that seam perfectly flush/flat per the manual? I'm not sure if that could prevent the pump from priming -- or just cause leaks -- but it's on the list...

Does the oil pressure gauge appear to work -- jump up to zero when ignition is on, as opposed to no signs of life?

Are you sure the assembly order is correct behind the timing belt gear -- oil pump sleeve, then o-ring, then washer, then gear?

Battery nice and fresh and spinning the motor with good speed?

Got plenty of oil in there?