Engine break-in oil pressure

[Alpineracer8]

Hey, everyone:

Got what I think may be a problem but I don't know for sure. I'm done with the motor in my Series I vintage racer (1600 cc) and I've been trying to get the motor pre-lubed prior to firing it up. I filled the sump with oil and even filled the oil cooler for quicker oiling. So far, so good.

Now, here's the problem, or at least what I think is the problem. I've been told that I should be able to get oil pressure to show up on the gauge (original mechanical unit) just by cranking with the starter. I've cranked and cranked and cranked, anywhere from 10 to 30 seconds at a time, and have so far not been able to show any oil pressure on the gauge. I have pulled the oil pressure line loose from the passenger side of the block and was rewarded with a puddle of oil on the floor before I was able to get it back together. I've also determined that there is oil getting to the brass "T" fitting between the two halves of the rocker shaft. By following the oil flow chart in the manual, it appears to have oil throughout the system, but still no pressure on the gauge.

So, what gives? I've got the plugs out of the motor so it cranks over at a pretty good clip (at least it does for a British starter...). What have the rest of you guys experienced? Is this pretty well what happens or do I have a problem? The gauge was working when I disassembled the car so I have no reason to think that the gauge is the culprit. Can someone shed a little light on what is quickly turning into a frustratingly bleak situation for me? I'm about at the end of my rope...

Thanks in advance,

 

[AndrewM]

Andy,

I doubt that you will be able to generate enough pressure to register anything on the gauge by just cranking the engine over with the starter, too few RPMs to generate any volume/pressure. I suspect that the gauge is not calibrated or accurate enough to show pressure at the RPMs that the starter is generating.

To be on the safe side and if you can, you may want to test/check that the gauge is working prior to start-up.

Andrew

 

[jumpinjan]

Cranking the engine (wo/plugs) will create enough oil pressure to visually read on the oil pressure gauge. I have noticed the same thing that it seems to take about a minute of cranking to see a response on the gauge.

 

[AndrewM]

Andy,

Jan is right! I went out and spun my Series V with out the plugs. The pressure guage did move, but after about a full minute of cranking (that a long time on that poor Lucas starter).

Andrew

 

[Alpineracer8]

Still no oil pressure...

I took y'all's advice and cranked on the engine continuously for 1 minute and 15 seconds...still no pressure on the gauge.

I've got two mechanic buddys, both with differing opinions (imagine that...). One is taking the optimistic road and is saying just gas it up and fire it off. He thinks that the oil pressure gauge may be stuck and it'll take more than just starter-generated pressure to move it. He also says that, since I do have oil that has evidently worked it's way through the motor, I should just light it off.

The other mechanic buddy of mine takes a darker approach. He says I should have built pressure at the gauge a long time ago and is suggesting that the engine is bleeding internally; i.e. we've done something stupid during the build. We took our time and made sure we left no stone unturned during the build so I can't believe that we would have pulled some bonehead move to cause this. On the other hand, I can't deny that I've got no oil pressure. 1 minute and 15 seconds of cranking...come on, something's wrong.

My next move will be to go down to Auto Zone and buy one of those cheap oil pressure gauge and line kits, remove the factory gauge line off the side of the block and install the new test gauge. That'll tell me right quick if I've got a gauge problem or something much more sinister.

Any other suggestions?

Rapidly losing patience in Oklahoma,

 

[alpine_64]

I think buying the test gauage is a good idea, yes you are getting oil to other parts, yes you have assembled carefully, but a test guage is a hell of a lot cheaper thank a crank grind and new bearings. Patience will possibly save you some big $

 

[sunbeam74]

Andy,

I get the feeling the pump isn't priming... I have had situations where pumps didn't prime - until started.

1) Did you fill the oil filter base with oil? Just remove the filter and fill the pipes leading up to the filter.

2) Did you fill the oil cooler and lines up? Messy but it takes a bit to fill a cooler.

3) Did you minimize the clearance on the oil pump?

4) Did you measure each rod journal and main and plastic gauge them?
Any irregularities?

5) Oil line going up to the rockers is tight and in place?

6) Oil pick up pipe and screen installed?

7) Front timing chain oiler in place?

8) Thrust washers?

Is this a 1725 or 1592 engine? There were sets of 1725cc main bearings that were mis-matched in the .010" size (standards mixed with .010" over) which were packaged by the factory... they still turn up on occassion.

Steve

 

[mikephillips]

You should have something showing. It's nearly impossible for the gauge to stick and register nothing unless it's in really poor internal condition. The needle is moved by a curled tube that tries to straighten out under the pressure from the line and then pulls the needle along with it. So either the gauge is broken internally or you've missed something in the rebuild. Did you install the timing change oiler during the rebuild?? Without that the gallery is open at one end.

 

[Paul A]

I think buying the test gauage is a good idea, yes you are getting oil to other parts, yes you have assembled carefully, but a test guage is a hell of a lot cheaper thank a crank grind and new bearings. Patience will possibly save you some big $

I agree with Michael. The cost of a new gauge is minimal in comparison with the cost of another rebuild.

I have rebuilt several Alpine engines over the years and have not experienced what you are. If, as you indicated, you were careful on the rebuild, it may very well be a stuck gauge. It certainly is worth the price of an Autozone gauge to check it out. Good luck.

from sunny South Dakota,
Paul

 

[husky drvr]

WAG - is there any possibility the front oil gallery plug is missing or loose?

 

[skywords]

For what it is worth, The new gauge is a good idea. I would try a sensitive direct reading gauge with a short hose in the engine compartment. If that produces no results then I would pre oil the engine by pumping some oil in thru where the gauge is connected (standard procedure on aircraft engines)Then start the engine and after 30 seconds if no pressure is indicated on the remote gauge then you truly have a problem.

It is more than likely the gauge on the dash/capilary is gummed up.

Good luck

Rick

 

[Nickodell]

You should have something showing. It's nearly impossible for the gauge to stick and register nothing unless it's in really poor internal condition.

Mike, I was taught many years ago that, to counteract a common fault with British engines of the pre-1970s - oil drain-down leading to zero pressure and oil starvation on startup - it is a good idea to run the starter for 15-20 seconds before pulling the choke and firing up, in essence priming the lubrication system. I've been following this practice for decades, with my old MG TC, two MGBs and two Sunbeams, and I have yet to see the gauge budge off the peg.

Matilda (SV), gets primed at every startup from cold, or even after standing for an hour after a run, and although her oil pressure is 25psi at idle and 40+ at speed, her gauge doesn't show squat during the priming stage either. This doesn't surprise me in view of the fact that cranking speed is maybe 40 rpm, compared with several 100 at idle.

Checking the pressure by connecting a low-reading gauge is great insurance; I just wanted to note that showing zero on the panel gauge at cranking speed is not necessarily a signal of trouble. Incidentally, there is of course more chance of showing some pressure if the oil is really cold (and more viscous), i.e if the vehicle stands outside in the winter. If the car is in a heated garage is is less likely

 

[Alpineracer8]

Update, guys...I now have oil pressure, and lot's of it, too! As it turned out, I pulled the pressure relief valve out last night and, bingo...the piston was stuck in a semi-open position. The valve I have is the brass one, which from what I gather is not the one to have. I've spoken with my racing mechanic buddy and he says for me to bring it to him tomorrow. He thinks he can either repair that one or make me a new one that'll work much better than the brass unit.

It was really amazing...I'm sure I've got the pressure adjusted too high, but when I started cranking the engine after freeing up the valve, it took 10 seconds for the gauge to start rising and by the time I got to 20 seconds of cranking, I had developed 40 lbs of pressure! As I said, I'm sure I've got it adjusted way too tight and before I start the motor, I'll readust it downward just to keep from blowing all the seals and hoses off the motor!!

Thanks for all the help and suggestions!

 

[64beam]

Hi Andy,

Great to hear that you found the problem so you don't get any unexpected surprises . A mechanic once told me that when cold, the Rootes engines can have quite high oil pressure (up to 60 Psi), but then drop to normal once at temperature. Definately a good idea getting the pressure relif valve repaired.
On a side note, I assume that the car has not been out on the track yet?

Regards, Robin.

 

[Alpineracer8]

Robin:

No, no track time as of yet. I've still got a little work to do yet prior to getting any track time...but it's getting closer...