Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing No oil pressure - help required

I recon only perhaps a minute from filling to screwing in the sensor to achieve a seal, then turning the engine over.
Given normally the oil pump would be left for a couple of months and not needing re-priming I cannot see the oil draining through the pump gears that quickly?
I'm using 20/50 which is not really thin?

I'm thinking move to vaseline next....also gives me a change to inspect the gears, (should i need new ones after 10K miles?) and pump for damage and freshen up the face to give a really good pump performance - given its the first time its lost prime in 35 years of being left for a few months and then started ok.

Thoughts?

Forced off its seat??!!!!! Goodness! I had no intention whatsoever to suggest THAT! In fact, why would the pressure valve be in the pump when trying this method? If present, the valve, with or without its spring, would act as a block to the oil being pumped in by oil can or syringe.If he tried that, it would explain the 100ml only. As I mentioned, once the plug (aka your "seat") is off, the spring pops out in a proper jack-in-the-box fashion, the valve should pop out in the happiest of worlds. After all the valve is supposed to be well-lubricated and freely moving, held by the spring and the threaded seat. If it doesn't pop out, this is merely more (though not 100%) evidence) the little thingie is stuck. I have removed the relief assembly more times than I can remember, experimenting with different springs and finally the adjuster I showed on my Plus 8s.


You wish to deal with the sender? That is another area. I was not commenting it. Jeremy's gauge oil pressure gauge signal is mechanical/hydraulic (is that the term?) ..like yours and all (5) of mine were before I changed them all to an electrical sender that makes the gauge an instant reading rather than a delayed one. I also reviewed the first posts, (sorry Jeremy). He has a 1990 UK Plus 8 like my1990 Plus 8 car, save his being a very early Morgan Hot Wire rather than one of the last L-Jets. . But its oiling system is the same as yours and my three. He has the plastic oil conduit from the oil pump to his gauge through junction on the bulkhead..like you do. I removed all that on all my Morgans)


But no less a great idea, worthy of investigation But I dislike going too far with someone else and THEIR Morgan. I can always remove my own pump when my Plus 8 is near at hand in September. I will put it back dry and unprimed and try the idea to re-prime. I have removed, changed and experimented many times with these pumps and their pressure relief system. I also have spare oil pumps and their innards. It is no big deal for me.

BTW, I did research back when and confirmed then that our stock tappets were still sourced from Detroit in our era..perhaps still. Back then, the company making them told me that the tappets were made with 20W50 in mind not the 10W40 recommended in the UK. .Like Jeremy, I use a decent natural motor oill 20W50 and 75ml. of ZDDP every 3000 miles. Frankly, frequent oil changes is the only trick to these engines longevity Nothing exotic about them. It is volume rather than high pressure system needing none of the benefits of synthetic.


A good discussion ALWAYS muddies the water. No way around it. Bottom line, I prefer experimenting with my engines and not others. But with your expertise, I would have no trouble with that.


Jeremy, why did you take out the sensor? I am curious because that would cause the hose to drain, wouldn't i?. And a drained hose would delay/interrupt the signal to the gauge.

I'm using 20/50 which is not really thin?

Yes. Me too. Mine have sat for a year of more with no problem for decades, except once decades ago after a improper oil change. Normally, a loss of prime is caused by an errant oil change. I have seen a lot of that with other Plus 8s owners. But..
1. engines are quioxotic
2. we are speculating of about a stuck-open pressure relief valve. That would mean the oil is freely allowed to flow back to the sump rather than pressurizing the system (and gauge)


Yes. Failing the easy successful experiment I would now go back to the Factory Manual and Vaseline. Be prepared, once you remove the oil pump face, the two gears will drop. Keep an eye out for a small metal filter. As for new parts breaking, engines and Morgans follow the Law of the Deadly Domino Effect (DDE). If something is faulty, it carries on down the line.

And yes. there IS then a way to check whether the camshaft gear is functional.

L.

As I understood, or perhaps misunderstood Jeremy had re-installed the oil pressure relief valve prior to removing the ELECTRICAL oil pressure sender unit to then provide access to the oil galleries into which he attempted to pump in some oil using the oil can. Of course I could have misunderstood the Process that Jeremy typed of. ?

I suspect the more that might be typed, the more room there is for confusion on what is a simple process of trying to prime the oil pump in the hope of restoring oil pressure, on the assumption that loss of prime may be the root cause..Thus at this stage of the conversation I will bail out, lest Jeremy thinks I might be able to offer worthwhile assistance..?

Keeping my fingers firmly crossed that the issue might be purely related to the pump loosing prime..which may not be the case..!

Luddite, you are correct in what you say above. PRV was reinstalled with 'tadpole' and new spring. I undid the small (not used) sender unit on the oil pump housing in order to have gravity working for me in refilling the pump chamber. Not the gauge sender unit that is fed from another take off on the oil pump housing.

Sorry for any confusion from my descriptions.
I do not have pics.

One question for Luddite - if it's not a 'prime' issue what could it be? Just so I can think a couple of steps ahead?

One questions for Lorne - the other way of priming the pump is through the distributor shaft? Assume it build pressure without turning over the engine. If I can get the car to a knowledgeable garage is that a more reliable method than the vaseline? I'm thinking the engine has been turned over few times with no oil, might be better to get the oil flowing by this method reducing risk of damage, before starting the engine?

Sorry Jeremy I missed your post. From that which I have only read, it is possible that during the process of changing both the oil and filter can be enough for the oil pump to loose prime..?
Thus when I change the oil in my +8, I fill the new filter with oil prior to fitting, which makes a bit of a mess when trying to screw it back in place, but it has worked well in the oil changes on my old +8 for over 20 years.

If you fit a dry filter, then I imagine that the oil pump has to have enough suck to raise oil from the sump, into the filter to fill it, before the oil reaches the pumps gears to then be pressurised into the oil galleries before ending up draining by gravity back into the sump to repeat the process...?

When an engine is shut down the oil is thinner, thus gravity can have an effect and perhaps more so over time, draining oil from the galleries and pump over time resulting in a rattle at start up..

Some oils seem better suited to regular lay up than others, as engine design altered in time and older type oils may be difficult to find.. I think Castrol Magnatec was a advertising campaign, suggesting the oil stuck to bearings etc better than other oild to provide lubrication on initial start up, which supposedly other oils may not..?

If the oil pump has worn due to poor oil quality, the possibility of crud being sucked into the gears, or the filter clogging due to irregular changes or even the filter it`s self perhaps being some sort of cheap counterfeit part that has caused some oil pump starvation and thus damage...

My guess was that trying to prime the pump, was just the simplest of processes to try first.

Still got my fingers crossed..

Jeez...! Sorry I was obviously typing when you posted your last Jeremy.... I am confused as to where you were trying to inject oil, in the pump housing.. if not into a known oil gallery, I suspect there is no chance of priming the pump.

Not having stripped a Rover V8 engine or oil pump, I leave it to those like Lorne and others with more practical or research experience of that engine and it`s issues.

I'll try and take a picture for you, there are 4 exits from the pump, this one I assume as its on top and has a pressure sensor attached is on the high pressure side on the chamber....will send pic a bit later. Thx

No need to get involved in trying to post a pic Jeremy, my suggestion was for a simple process, no need to add further complexities at this stage. you may remember that i typed of witnessing the oil pressure gauge needle returning to zero on the engine equiped with a mechanical gauge. given by using the pump action of the oil can I obviously had raised enough pressure in the oil galleries to register on the gauge.... If using other than the oil pressure release valve orifice to introduce the oil can nozzle, and IF you still have the oil pressure release valve in place, then It seems possible that you may be using the oil pressure switch position to introduce oil...?
Any of the three take off points mentioned logically have direct access to the oil galleries.
My Mid 80`s +8 may be different to the set up on the +8 in question. I also do not have the suspension oiling system on my Mog.

Here is a diagram of the pump housing.
https://ibb.co/k6h85CQQ

Item no. 10 is the sensor that I removed and filled with oil, its on the top of the housing and allows you to fill using gravity as well as pressure from the oil can.
I assumed that would be on the high pressure side of the pump and provide immediate access to the pump volume where the gears are.

The PRV no. 7&8 is on the other side and points down, thus as an access route you are working against gravity. The RVR was assembled and in position. So should stop any oil in the chamber being returned to the sump.

Hope that clarifies the entry for priming.

Thx for all you help

Fairley clogging up the forum on this subject...? (-:
Item No 10 on the diag, would appear to be an oil pressure switch which logically detects oil pressure in the galleries, thus should be an ideal access point. However the whole idea of using a oil can with the ability to pump the oil, is that it can be used to create pressure in the system to the extent you feel it taking more physical effort to operate the pump action on the oil can, and with a bit of luck if you still have the oil pressure sender unit in place and electrically connected, with the ign on there is a chance that the gauge may (if operational) may just display some measure of the pressure that ideally you are introducing to the galleries via the oil can..?
From the diag it also seems that there may be a gauze filter adjacent the oil pressure release valve... Wonder if that may be playing a part... Hmm..?

I reiterate that I have never had any of this kit apart on my +8. I am using no more than logic (failed or otherwise) in this regard..