Can't seem to crank up any oil pressure.

wild man · 12-11-2010, 03:02 PM

After replacing many things such as belts, rollers, seals, camshaft, turbocharger, and piping, today I was to the point where I could crank the engine, with the coil wire disconnected, to try to build some oil pressure. If I recall correctly, cranking the engine should produce about 2bar (20W50 @ low outside temp) of pressure. But after 4 or 5 20-30 second cranking sessions, I'm not even seeing 1/2bar come up on the gauge. Any ideas on what could be wrong? Could I have possibly caused the oil pump drive to become disengaged when I changed the front crankshaft seal?

Ga 951 · 12-11-2010, 06:40 PM

Did you torque the crank bolt to 155 ft/lb (IRRC) ? Necessary for the oil pump to work properly.

Pete R · Pete R's Garage

Why does does the crank bolt matter? The oil pump seems to be driven off a keyway'd gear. Did you do an oil filter too? and Is the motor cranking nice and fast? Maybe it's just taking a little while

John_AZ · 12-11-2010, 07:56 PM

Quote:

Originally Posted by Pete R

Why does does the crank bolt matter? The oil pump seems to be driven off a keyway'd gear.

The oil pump is driven by the "oil pump sleeve"-----no keyway.

John

speedracing944 · speedracing944's Garage

Make sure the crank shaft bolt is tightened to the spec 150 ft-lbs IIRC. Then remove the oil filter and pour oil from a fresh can into the center oil tube. This will flow down into the oil pump and "prime" it. With the coil wire off try cranking the engine and report back.

Speedy

Techno Duck · Techno Duck's Garage

Make sure you put the thrust washer on in the right direction.

Check crank bolt torque.

Make sure power steering pulley is seated correctly.

Pulling the plugs out will help also.

Also you should be able to get well over 2-bar with 20w50, especially in these temps.

TibetanT · TibetanT's Garage

If you have tried everything HERE above, then my best guess is:

1) When the sleeve and seal were assembled, you did not ensure that the teeth on the sleeve was embedded/married correctly with the oil pump internal gear.

I had this happen once a long, long time ago...my first timing belt job. Since it was a new procedure to me, at the time, I never realized that the sleeve was seized within the camber. In fact, I thought I was really cool because I placed the seal on the sleeve before I even put the sleeve on the shaft.

In other words, if the sleeve doesn't quite mesh with the oil pump internal gear, then the oil pump is not turning. Thus, no oil pressure...period.

If it was me, I would take everything apart again and do it step-by-step slowly to ensure everything is back correctly. I know, I know...PITA.

Hope this helps and good luck.

bazar01 · bazar01's Garage

A timing belt changge and a reseal don't normally cause a no oil pressure on start up because the oil galleys are still filled with oil unless the crank bolt is loose or the power steering pulley in the crank is not seated properly on the crank journal end as mentioned earlier.

wild man · 12-12-2010, 05:35 AM

I know the crank bolt is torqued to over 150 ft/lb. Not sure about PS pulley seating though. I did a PS pump delete (now permanent, since I broke off the split ear, trying to knock out the inner spacer), so I don't even think the pulley needs to be there, does it? Not sure about the thrust washer either, now that everything is back together (didn't know it could be installed backwards). I do remember pulling the oil sleeve out about 1/4" to inspect it for groovage, after removing the old crank seal. It did have some groovage, but I decided to let it go, unless it starts leaking, or until next belt change, whichever came first. If what the tibetan T is saying is true, that might indeed be the case, considering what I remember doing, because I don't recall checking to see if the sleeve gears were locked in when I slid it back in, before putting the new seal in. I never changed the oil or removed the filter, but the cam tower was removed when I swapped in a late camshaft. Could I have screwed something up there that would cause lack of oil pressure? I will try a few more cranking sessions today. If no-go on OP, then it looks like tear-down time again (now in freezing temperatures).

Lawrence Coppari · 12-12-2010, 06:38 AM

I ran into that problem with my 951 many years ago. I removed the spark plugs so that I could crank it faster. Oil pressure refused to come up. I had had the crank pulley off to replace the water pump but had it torqued properly.

So........I just started the engine. Oil pressure came up immediately. That was about 60K miles ago so I have to assume not damage was done.

wild man · 12-12-2010, 07:11 AM

Quote:

Originally Posted by Lawrence Coppari

I ran into that problem with my 951 many years ago. I removed the spark plugs so that I could crank it faster. Oil pressure refused to come up. I had had the crank pulley off to replace the water pump but had it torqued properly.

So........I just started the engine. Oil pressure came up immediately. That was about 60K miles ago so I have to assume not damage was done.

Man, this is a tricky one. With plugs removed, it will crank at faster than idle speed, which worry's me that I will collapse one or more lifters (or cause other damage) if OP doesn't come up, considering that they have been removed for a cam swap, and there is only assembly lube on them and the camshaft.

I really don't like this. It might be that I need to tear down the front of the engine again, or it might be nothing at all? I'm thinking the cold weather and heavy oil weight might be causing the pump to have problems drawing it up the tube, but I don't know. I am about ready to go out and try cranking it some more.

Lawrence Coppari · 12-12-2010, 08:33 AM

Mine was in my basement when I did it. It was in the low 60's F. Oil was Mobil 1, 15W-50. That the oil pressure did not come up had me puzzled. Mine's an '86. Could it be that the gauge did not function when the key is turned to start (crank)? I cranked mine for maybe 20 seconds with plugs out on 2 occasions. Needle never even quivered. I finally gave up started the engine and it came up immediately.

Good luck.

wild man · 12-12-2010, 08:52 AM

Currently having a dry top-end (I DID use assembly lube on the cam and lifters) is what concerns me the most about that approach. I previously have been able to crank up pressure after changing the oil and filter, before connecting the coil wire and actually starting the engine, for the purpose of pre-filling the filter. For me that is standard procedure when changing an oil filter on one of these engines.

I'm not quite ready for full start-up yet, but maybe I'll try that approach using a 5-second max count.

HondaDustR · 11:18 AM

You have to make sure the power steering pulley sits around the crank and is not inadvertantly clamped between the end of the crankshaft and the shoulder washer of the crank bolt. What will give it away is that the pulley will wobble eccentricly since it is not centered. There is a washer, pulley, 2 sprockets, washer, oring, drive sleeve sandwitch that is supposed to hold everything solidly to the crank, and if anything is out of place, flipped backwards, or missing, the bolt will just torque up against the crank and not transmit force to the drive sleeve to hold it. Because of this, you cannot just leave out the power steering pulley without getting the different crank bolt washer that is stepped deeper in order to reach further around the end of a power steering crank to be able to clamp the rest of the hardware. The early cranks that did not come with power steering had a slightly shorter end section that did not require a special washer IIRC. It has to be some sort of problem in this assembly, since the only way to really lose prime is to replace the pump or tear down the bottom end.

I have noticed that once it started dropping into the 40's, the 20W-50 Brad Penn oil I'm running would build pressure much more slowly on startup. It will relatively slowly crawl up to the peg over the course of 2 or 3 seconds rather than popping right up. A quart of Mobil1 0W-20 helped that out to hold me off until oil change time coming soon, but 20W-50 gets hard to move at low temps. You could just start up briefly. If you don't see oil pressure in 5 seconds, something is wrong. That's about how long it takes most cars to fill up a new oil filter, so it shouldn't hurt anything. There should still be some oil in the bearings, but as I said, if front main seals is all you did and it was assembled correctly, then this shouldn't be a problem unless it's really cold out and you're filled with heavy oil. The state of the top end should not affect it and the assembly lube will do its job and protect it. Last time I swapped some lifters, the pressure came right up as normal.

wild man · 12-12-2010, 11:18 AM

I just got to thinking, having the dip stick tube out couldn't possibly make any difference could it (just came in from trying to crank it some more - no beans). It's pretty crappy out there today - raining all day long so far.

But what if I had someone apply some (regulated) air pressure to the DS hole while I'm cranking it over to try to get the pump primed that way?

Should I pop a cam plug out and try to look inside to see if there is evidence of any oil flow?

When the ignition is off, the pointer is below the 0 line, and is right on it when the ignition is turned on. It moves up only like a "C" hair when it is being cranked. I did notice that voltage is showing very low when cranking though. Would that affect the gauge? The low pressure light DOES NOT go out when cranking it.

HondaDustR · 12-12-2010, 11:27 AM

Quote:

Originally Posted by wild man

I just got to thinking, having the dip stick tube out couldn't possibly make any difference could it (just came in from trying to crank it some more - no beans). It's pretty crappy out there today - raining all day long so far.

But what if I had someone apply some (regulated) air pressure to the DS hole while I'm cranking it over to try to get the pump primed that way?

Should I pop a cam plug out and try to look inside to see if there is evidence of any oil flow?

When the ignition is off, the pointer is below the 0 line, and is right on it when the ignition is turned on. It moves up only like a "C" hair when it is being cranked. I did notice that voltage is showing very low when cranking though. Would that affect the gauge? The low pressure light DOES NOT go out when cranking it.

I'm pretty sure air at the dipstick will do nothing, since it will just exit out the AOS breather hose. If your battery is getting low, it could possibly affect the gage, but it's just a voltmeter measuring variable resistance of the pressure sensor. It may read a little lower, but I have seen at least 2-3 bar from cranking. If you haven't already, remove the plugs. You'll save your starter and battery and gain some rpm. We're assuming that the sender connections haven't been undone for something and installed incorrectly.

Just how cold is it anyway?

wild man · 12-12-2010, 11:29 AM

Sorry, didn't see honda duster's post- must have been writing at same time. I understand what you are saying about needing the PS pulley to be on there (it is). I will get someone to crank it over while I check for any pulley wobble. It will be a couple of days anyways, before the engine will be fully ready to run (aside from this issue). I still need to finish fabbing up the 3" intake pipe, with all of the nipples, for the K27.

wild man · 12-12-2010, 11:39 AM

That was twice in a row!

OK, I'll check the sender connection. I AM running PB 20W-50, and HAVE seen 2-3 bar from just cranking (in warmer weather). Yesterday it was running close to 50 and dry, so I got a lot of work done, but there is still more to do before it is ready for startup. If you really want to know, today sucks. Fairly nice temp at mid 40's, but solid rain, all day long. Typically seeing highs in the upper 20's lately though.

speedracing944 · speedracing944's Garage

Have you tried to prime the pump with oil through the oil filter hole?

Speedy

HondaDustR · 12-12-2010, 03:29 PM

Quote:

Originally Posted by wild man

If you really want to know, today sucks. Fairly nice temp at mid 40's, but solid rain, all day long. Typically seeing highs in the upper 20's lately though.

Oh yeah...BTDT. I've laid in my fair share of wet driveways that's often wet with more than just rain.

I tell you! The weather PLANS for me! More than 50% of the time it seems, no sooner than I get all the tools out and the airbox/wheel/whatever off, it starts raining. Getting rained out was most of the reason I forgot little wads of shop towel in my head that killed the motor, too.

By far the worst was re-installing the cam belt one Sunday night in December so I had a car to get to school with the next day...and this was back when we lived right on the potomac river. 20 degrees and 30 mph winds made for some pretty good hell...working in 5 minute shifts and had to keep taking the tools in and running hot water on them so I could hold them. Clutch hydraulics job a couple months later wasn't much better. Oh yeah...good times with no driveway and keeping a DD reliable.