Oil pressure sudden change
- Thread starter JimNH
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Faulty oil pressure gauge
Oil pressure relief valve partially bridged open with debris (not likely)
Oil pressure relief valve broken/damaged spring (not likely)
Crankshaft lip seal on timing side cover damaged.
Oil pump giving up the ghost - maybe passed something through that it should not have and damaged the pump.
Oil pump loose and blowing by gasket surface.
Damaged oil pump rubber seal between timing chest cover and pump
Any change in engine noise associated with this apparent drop in oil pressure? I would verify the oil pressure reading and go from there.
Oil pressure relief valve partially bridged open with debris (not likely)
Oil pressure relief valve broken/damaged spring (not likely)
Crankshaft lip seal on timing side cover damaged.
Oil pump giving up the ghost - maybe passed something through that it should not have and damaged the pump.
Oil pump loose and blowing by gasket surface.
Damaged oil pump rubber seal between timing chest cover and pump
Any change in engine noise associated with this apparent drop in oil pressure? I would verify the oil pressure reading and go from there.
Next check will be timing cover to pump seal.
No change in engine noise or performance.
This engine normally pegs 60 PSI gauge when cold and has pegged 80 PSI test gauge as well. I believe it's quite possible it blew timing cover seal; at least that's what I hope.
No change in engine noise or performance.
This engine normally pegs 60 PSI gauge when cold and has pegged 80 PSI test gauge as well. I believe it's quite possible it blew timing cover seal; at least that's what I hope.
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JimNH said:
I have blown out a few timing cover crankshaft lip seals before.
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Might undo feed to head to see which part of engine restricting oil flow. Kink in head feeds? Most the listed oil area would bleed pressure lower not higher. Most the flow goes thru crank but have not heard of sludge trap flakes plugging big journal holes with sling force added but does cross a through worry wart mind. I have seen the multi wt oils settle out for honey like mass at bottom of stored bottles as only other thing I can conceive to worry about. Maybe just a cold summer temp spell that will pass.
Timing cover seal blown:
I also found the anti wet sump valve open again. It just seems the spring is too weak. I'll polish it up again and stretch the spring a bit.
In reading old threads I see some are of the opinion that an oil pressure gauge is a bad idea on a Norton. I'm firmly in the other camp. This engine always has about 50PSI or better above 3000RPM. The gauge found the sudden change. The relief valve spring is not shimmed. In fact, it exerts no tension on the valve statically.
I also found the anti wet sump valve open again. It just seems the spring is too weak. I'll polish it up again and stretch the spring a bit.
In reading old threads I see some are of the opinion that an oil pressure gauge is a bad idea on a Norton. I'm firmly in the other camp. This engine always has about 50PSI or better above 3000RPM. The gauge found the sudden change. The relief valve spring is not shimmed. In fact, it exerts no tension on the valve statically.
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Sticking to actual historical facts it was Norton authorities like Mr. Hudson that warned about the fear factor and avoiding more bad PR of installing oil gauges AFTER about a season of factory gauge options install that got freaked out owners reporting to every dealer so the hot patato was dropped. So it not a bad idea to know what the pressure is DUH, but lack of hyw cruise oil pressure was and maybe still is common w/o harm is all. Do not confuse ideal hoped for oil pressure with quite adequate though no reason but time and money to do what it takes to get about 10 PSI per 1000 rpm once hot. Upping oil grade thickness is the historical way. IIRC this oil gauge scare event happened shortly before the Combat Bomb era. Newbies should be aware there are 3 items to match for correct oil pump seal to TS cover, the gasket behind pump, nipple on front of pump and TS cover gasket and Old Brit sells the correct matched pairing for 850 or 750, either way - if matched gasket/nipple pair installed.
So why did this instant case spike PSI which has its downsides too.
So why did this instant case spike PSI which has its downsides too.
hobot said:
I'd be OK with 10PSI/1000RPM, if that was the norm for this engine. If that was the norm and it suddenly fell to 3PSI/1000RPM, which is about what it did, Then I'd be investigating as it would indicate a problem.
The main reason I installed a gauge in the first place is that I found the timing side crankshaft oil seal rolled. I think I know when that happened and I hadn't run it again until I found it.
In the fall I may to go to a lighter weight oil.
I think 10 psi at idle with hot oil is a bit optimistic. Going down the highway at 70 to 80 I get around 50 with hot oil. I really feel that the gauge is there to prove pressure rather than tell us how much we have, although witnessing a sudden drop or spike could save big money and lots of time.
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It is good to see that all went well. Oil pressure gauges do work. Would you fly an airplane without one? :shock:
Mike Partridge told me that they create more problems than they are worth on a Commando....but that's only if you don't take care in how things get routed. Lots of vibration on a norton...don't ya know!
Thomas
CNN
Mike Partridge told me that they create more problems than they are worth on a Commando....but that's only if you don't take care in how things get routed. Lots of vibration on a norton...don't ya know!
Thomas
CNN
CanukNortonNut said:It is good to see that all went well. Oil pressure gauges do work. Would you fly an airplane without one? :shock:
Mike Partridge told me that they create more problems than they are worth on a Commando....but that's only if you don't take care in how things get routed. Lots of vibration on a norton...don't ya know!
Thomas
CNN
In fact it was an oil pressure indication that preceded the only turbine engine loss I ever experienced. The chances were pretty low that it would ever happen but it did. Hopefully it will never happen to me again. #2 engine on a 3 engine plane so not too exciting.
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Well Jim,JimNH said:CanukNortonNut said:It is good to see that all went well. Oil pressure gauges do work. Would you fly an airplane without one? :shock:
Mike Partridge told me that they create more problems than they are worth on a Commando....but that's only if you don't take care in how things get routed. Lots of vibration on a norton...don't ya know!
Thomas
CNN
In fact it was an oil pressure indication that preceded the only turbine engine loss I ever experienced. The chances were pretty low that it would ever happen but it did. Hopefully it will never happen to me again. #2 engine on a 3 engine plane so not too exciting.
It was good that it was a triple and not a single engine. You would be looking for some lonely highway without power lines. or something worse. maybe a corn field which would probably be used to produce ethanol. DAMMN. lol :mrgreen:
Cheers,
Thomas
CNN
A
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Oil gauge? Wouldn't leave home without one! 50 psi instantly at startup and such a comfort on at stinking hot day at 4000rpm to see the needle sitting stable at 25psi.
Ta.
Ta.
Nortons don't need no stinkin' oil pressure gauge. When the rear wheel locks up and you skid to a stop, you'll know something is wrong. Pulling in the clutch will let you know if it's engine or tranny lockup. I guess knowing an engine lockup from lack of oil pressure is imminent is just too scary, for some.
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