Lorne I very much doubt that the oil pressure relief valve would be forced off its seat during the attempt to prime the pump using an oil can,
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.
My thinking is currently that Jeremy`s description of removing the oil pressure sensor a fraction of a turn at a time relative to spanner access, caused me to then imagine how much time had passed prior to him replacing the sensor and then turning the engine over....
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)
As I typed I have not tried this method on a Rover V8 and on both occasions I used it the issue was resolved..
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.
As before, hope this helps and does not muddy the water.... ?
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.
I recon only perhaps a minute from filling to screwing in the sensor to achieve a seal, then turning the engine over.
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.
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?
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)
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?
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.
