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Posted by: DavidSweden Apr 26 2015, 11:03 AM

Well as the title says is all gone tits up.
I started my rebuilt engine yesterday and broke in the cam, today was supposed to be the first drive. I decided to check the actual oil pressure so I pulled the pressure switch and connected my gauge. There was no pressure even at 2k rpm.

The pump is working but there is no pressure. Obviously the oil must be going somewhere, if the high pressure relief plunger is stuck open would this explain what's happening?

Appreciate some help

Posted by: stugray Apr 26 2015, 11:10 AM

Stupid questions first:
You DID put the oil in? ( In know most will say stupidest question ever, but I have done it once)

When you installed the pickup tube in the case, you put in the black o-ring?

And since you mentioned the oil pressure relief plunger, you put that in with the spring?

What you have just experienced is EXACTLY WHY I installed a mechanical oil pressure gauge BEFORE I cranked the engine to build pressure for the cam breakin.

Sorry to say this but: If you ran the engine long enough to break in the cam, and you had no oil pressure, then you almost assuredly killed the engine.

Posted by: DavidSweden Apr 26 2015, 11:14 AM

I installed the above

How can I tell if "I killed" the engine?

Posted by: ConeDodger Apr 26 2015, 12:03 PM

Pretty sure you didn't run the cam in with no oil pressure, no oil etc. You would know. It wouldn't even take 20 minutes and you would know...

Mechanical gauge problem...

Posted by: DavidSweden Apr 26 2015, 12:34 PM

I checked the gauge with compressed air and it works. I agree that some oil must have been circulating otherwise the engine would seize? If the pump is pumping then the oil must be going somewhere?

Posted by: stugray Apr 26 2015, 12:42 PM

The oil follows this path:

Oil pickup into pump, out of pump to oil filter bracket, out of oil filter into case where the oil pressure sensor is.
From there it can go two ways: dump back to sump if oil pressure relief valve is open, OR go to oil cooler, THEN back into engine to the bearings.

Here is a diagram of the system if you ignore the filter sandwich plate:


If the oil pressure sender (switch) port is dry, then none of the engine got oil.

Is the filter full?

Posted by: DavidSweden Apr 26 2015, 12:45 PM

Yes filter is full, there is oil in the gallery under the pressure sender.

Posted by: stugray Apr 26 2015, 12:55 PM

Then the only explanations can be:

A - Oil pump not putting out significant pressure - not likely failure, even severely worn pumps will put out SOME.

B - Oil relief valve stuck open or spring missing

C - Oil pickup leaking (sucking air) - was there foam in the oil filter?

D - Missing oil galley plug or hole in case.

If I recall from my case oil passage inspections, there is at least one oil galley plug somewhere in the case that is put in place to seal between two passages, then a second oil galley plug is put in after the first one (not positive on that, but it rings a bell)
Did you have all of the galley plugs removed, and re-installed?

E - Pressure gauge does not work when installed in port.

Posted by: DavidSweden Apr 26 2015, 01:05 PM

First thanks for helping me out
No foam in the filter, I removed the smaller gallery plugs and replaced them, if one of these was missing there would be a lot of oil under the engine?

If I open the safety relief valve do I need to drain oil from the engine? I am thinking that maybe the plug is stuck and the oil is not going to the sump but to the gallery, I did install the spring.
I am thinking of starting the motor with a tube attached where the pressure switch is to see how much oil is coming up....good idea?
If there is no oil circulating surely the engine would of seized?
http://s1300.photobucket.com/user/DavidGbgSweden/media/oil%20system.2_zpsqywry2ed.jpg.html

Posted by: The Cabinetmaker Apr 26 2015, 01:52 PM

Stock pressure sensor ? An aftermarket gauge may not work with the stock sender.

Posted by: DavidSweden Apr 26 2015, 02:11 PM

I am not sure what you mean

This is what I am using

http://s1300.photobucket.com/user/DavidGbgSweden/media/15-1390_xl_1_zpsipgnrmff.jpg.html

Posted by: McMark Apr 26 2015, 02:23 PM

Im still liking the oil pressure piston for this.

Posted by: DavidSweden Apr 26 2015, 02:49 PM

Thanks, was planning on removing it. Question: Do I need to drain the oil and what should I look for when I get it out?

Posted by: Jeff Bowlsby Apr 26 2015, 02:51 PM

Don't these engines have ridiculously low oil pressure anyways? What is a normal value...something like 3-4 psi?

Posted by: r3dplanet Apr 26 2015, 02:52 PM

Snap a photo of that piston? I think there are two types of pistons that fit - one for the 914 another for the bus. They both fit. Maybe it's the wrong one?

Posted by: DavidSweden Apr 26 2015, 03:04 PM

Jeff,

I dont know for sure but shouldn't I have 10 psi at idle and 20 at 2k+?

And thanks for the MPS it works a treat

Posted by: DavidSweden Apr 26 2015, 03:09 PM

Ok, I heard or read someplace that the piston could be replace with a ballbearing and washer anyone got any info on this?

Posted by: DavidSweden Apr 30 2015, 10:34 AM

McMark,
You were right! The piston had sharp edges and had stuck, I am not sure how far down it was but I hope I have not damaged my engine considering I ran it for 20 minutes to break the cam in. I took of the edges with some fine emery paper and reinstalled. The pressure is now 10 psi when warm at tick over and the engine sound ok to my newbie ears.

You live and learn and thanks to everyone who took the time to help me out....again

Posted by: toon1 Apr 30 2015, 11:52 AM

It's supposed to be a minimum of 11 at idle on a warmed up engine.

With mine, I will get 0 at idle after a long run, even with bradd penn 20/50 after an oil change.

If I idle more than 30 seconds the pressure slowly returns.

Once I blip the throttle, normal pressure returns

Posted by: stugray Apr 30 2015, 01:01 PM

I get >60 PSI at startup with 20w50.

After 20 minutes of hard driving, it will drop to 20 PSI at (slightly high) idle.

And it will drop to 10 PSI (where my warning light turns on) when the idle drops so low that it is about to die.

Posted by: DavidSweden Apr 30 2015, 01:06 PM

Is that with the stock oil pump?

Posted by: Java2570 Apr 30 2015, 01:14 PM

Stu - are you checking the pressure reading at your gauge plumbed in by the pressure sender or the gauge in the console? I have a pressure gauge in the engine compartment similar to your setup.....my VDO gauge reads about 6 psi at full warm but the external pressure gauge is over 10 psi. I put that external one in after seeing your setup and wondering how accurate the VDO gauge is....

Posted by: stugray Apr 30 2015, 01:18 PM

I am honestly embarrased to say "I dont know".
The 2.0L engine came from the PO of my 71 1.8L car.
I built it up and paid meticulous attention to everything EXCEPT measuring the gears on the oil pump.
It had a steel cover not the stock-like one.
I did check it and it had no interference with the cam gear engagement that required modification.

And that pressure is AFTER traveling 30 feet to the front oil coolers and back through 12 AN hose.

I was able to get 35-40 PSI just cranking the engine with the starter before I fired it up for cam breakin and then I installed the oil coolers.

Posted by: jsaum May 1 2015, 08:31 AM

I would drain the oil and check for metal flakes just to make sure you haven't damaged anything before you try starting it again.

Posted by: stugray May 1 2015, 08:56 AM

Both the vdo and the mech gauge are plumbed to the pressure switch port and read very close to the same value.

Posted by: DavidSweden May 1 2015, 11:38 AM

Well I thought that I had found the problem but it would appear not. I took the car out for a short spin. There was oil pressure when I started. The engine ran very well, then when I pulled up I at a stop light the idiot light came on, I reved the engine and at around 2000 I got pressure.
To summarize; The idiot light comes on when the engine is warm and under 2000 rpm.

Anyone got any ideas?

Posted by: stugray May 1 2015, 01:14 PM

One thing that can cause low oil pressure in a system that has properly operating oil pump & pressure relief: Worn out bearings.

Posted by: r_towle May 1 2015, 01:22 PM

when you built the motor, did you keep turning the crank shaft by hand, and specifically did it easily turn when you tightened up the case halves together?

There are pins in the bearings, if you have a bearing mis aligned, the pin wont fit in the hole...and the crank is really hard to turn all the way around...
It will turn, but not easily...

That will also mean the oil galley is blocked because the hole in the bearing is not lined up.

Rich

Posted by: Java2570 May 1 2015, 01:29 PM

Is it possible the pressure relief valve got stuck again? Otherwise it sounds like a blockage or bearing issues as was mentioned by Rich and Stu....

Posted by: DavidSweden May 1 2015, 01:30 PM

Rich,

The engine turned over nicely and I was careful to get everything lined up. If the gallery was blocked wouldn't the pressure increase? Anyhow I will get the car on the lift tomorrow and check the suction pipe and have another look at the pressure relief valve. The engine runs great (except for the oil pressure) I guess I messed up somewhere along the way.

Posted by: stugray May 1 2015, 03:24 PM

I thought you's get the hint from the

What I believe happened (but hope not) is that the pressure relief piston froze during your 20 minute cam breakin period (at the 1 minute point or the 19 minute point? )

Then the bearings took the brunt of the abuse and are already toast.
This would look just like a very old tired motor with respect to oil pressure.

As the bearings wear, the clearances open up reducing overall system oil pressure.

I just moved the "Racer Chris oil pressure relief valve upgrade" up on my list of next things to buy.

http://www.914world.com/bbs2/index.php?showtopic=236704

Posted by: DavidSweden May 1 2015, 03:51 PM

Stugray,

You may be right and the bearings are toast, at the moment its just too painful to consider. As I did have oil pressure (the idiot light was off) during breakin I am hoping there ok. as you will understand, before I drop and tear into the engine I must see if the lack of oil pressure is due to something else....you never know I may get lucky

Posted by: PotterPorsche May 1 2015, 09:07 PM

What about removing all the excess oil lines. Like the ones that run to the front. 12 an line is quite big for I assume a schadek 30mm pump.

Posted by: stugray May 1 2015, 10:14 PM

I think you are getting confused.

The OP DavidSweden, does not have the extra oil lines.
His system is totally stock, recent rebuild.

Posted by: DavidSweden May 4 2015, 01:18 PM

It was a bitter decision... The engine is out and I have begun the tear down.
There was oil in the pump and it seemed to be ok, The cooler had some oil in it but I guess most it drained out when I emptied the sump. I had a good look at the pressure piston bore and noticed it had what looks like a score in it I guess thats where the piston hung itself. I remember thinking that the spring needed a lot of compression during installation. Next step open the case and look at the bearings. All that work gone up in smoke it just sucks

http://s1300.photobucket.com/user/DavidGbgSweden/media/pressure%20releif2_zpsrwpbphcj.jpg.html

Posted by: stugray May 4 2015, 01:29 PM

You can inspect the cam without splitting the case halves.

That ridge in your picture is the topic of many threads.
The Tangerine racing pressure relief valve was specifically designed to avoid that problem.

Others have honed it down to eliminate sticking

Posted by: DavidSweden May 4 2015, 01:43 PM

Stugray
I just sent a mail to Chris and ordered the Tangerine racing pressure relief valve, thanks for pointing me in the right direction.

Is there much point in inspecting the cam I guess I will need to split the case to change my bearings....Is there a chance there not toast?

Posted by: DavidSweden May 18 2015, 10:13 AM

Well after dropping the engine I found the source of my oil pressure problem, I now have oil pressure 60 psi on cold idle going to 20 when warm, (have not installed Tangerine relief valve yet).
However I now have a steady oil drip coming from between the gearbox and engine, I guess it must be the flywheel oil seal?

Question; Is it easy to remove the gearbox without dropping the engine to get at the seal and is there anything to look out for?

Thanks

Posted by: Phoenix914 May 18 2015, 10:45 AM

So, what was the problem? Do you think there was any damage done, or still not sure?

Posted by: rjames May 18 2015, 10:45 AM

Yup- gearbox is fairly easy to remove by itself. Pelican has an excellent writeup on how to do it as part of their '914 clutch replacement' tech article.

http://www.pelicanparts.com/techarticles/914_clutch_replace/914_clutch_replace1.htm

Posted by: DavidSweden May 18 2015, 10:57 AM

Thanks, appreciate it

Posted by: r_towle May 18 2015, 11:05 AM

seriously, what was the problem?

Posted by: DavidSweden May 18 2015, 03:19 PM

Well I made a major mistake while pulling the oil gallery plugs. just before I was about to drill a hole in one of the plugs the phone rang and my wife started going on about what I was going to cook for dinner etc. After I got off the phone I suffered a complete meltdown in concentration and drilled into the case in the wrong place (entirely my fault). I drilled one of the plugs located on the side of the case by the passage for the oil relief piston. I realised the mistake immediately although I was not aware at that point of the consequences. To cut a long story short I drilled out the case threaded the hole and inserted a metal plug. As the relief piston was not installed I did not realize that the plug was too long and stopped the piston from seating in the closed position.
http://s1300.photobucket.com/user/DavidGbgSweden/media/oil%20piston_zpsioxi33yu.jpg.html
This picture was taken after I had removed the engine to find the cause of the problem, the oil relief piston is clearly visible. Yes I do feel pretty stupid but I guess shit happens.

I installed a shorter plug so the piston is now free to travel. The engine fires up no problem and as I said I have 60 psi at cold idle dropping to 20 when warm. I just hope the cam and bearings are ok. I will take the car for a drive during the week and see how it feels. During the rebuild the flywheel seal did not go in straight so I tapped on the other side and got it square (I thought). I now have a steady drip from the observation slot under the fly wheel.
I plan to replace the seal if the engine runs ok. I will gladly take advice regarding the correct procure for installing the seal so I get it right this time
The engine build has been a painful as well as educational experience....I guess you would call it learning by doing. Hopefully my next build will be better.

And thanks to everyone who has taken the time to help me out, I do appreciate it.

Posted by: r_towle May 18 2015, 07:15 PM

Thank you, it's always good to learn something.
Never talk to the wife while working on an engine, check

Posted by: Jmkorfha May 19 2015, 06:04 PM

Back in 1982 i just got done with a complete rebuild on my 73 1.7 litre. Everything was new, reground crank, new cam, all new bearings, the works. As I was finishing up, I installed the new oil filter and thought it felt "wierd" as I tightened it. Drove it for a couple days when I noticed the oil light was brighter. I parked at the drugstore and looked under the engine. No filter. After installing a new filter and oil, everything worked fine. Good power, good oil pressure. The only thing that bothered me was that faint noc noc noc sound they all make when running. Turns out I had driven for about 2 miles without the filter.
It bothered me so much that the next year I ordered new crank, rod, and cam bearings and tore it down.
All the bearings looked perfect. There was no damage whatsoever. I replaced them anyway and re-installed the engine. It sounded and ran the same.
I know my story is not the same as yours, but if I was in your shoes, I would drive it and wait to see if something turns up. Sometimes what we imagine could happen is worse than what really does.

Posted by: DavidSweden May 20 2015, 08:56 AM

Yes thats exactly what I am going to do, drive it and see. I am sure (nearly) that it's going to be fine

Posted by: r_towle May 20 2015, 11:58 AM

good luck, glad you found it.

And thank you for sharing.

rich