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Can oil pressure too high damage something ?

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Ed_K

Ed_K

Jedi Knight
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While changing the oil and filter today, I took the opportunity to remove the oil pressure bypass spring and plunger to check it's condition. The plunger looked to be in good shape but the spring was about .2 " inches shorter than the shop manual listed.
I stretched it out to the proper length, then to check if it would stay, I installed it and then removed it again from the engine. The steel must be old and tired because it shortened back up to the .2 " under spec. I found a nut that was the same size as the opening of the cap and .225 " thick. I installed the nut in the cap under the spring and then screwed it back in the car.
Before this oil change, I was running dino castrol 20w-50 . It would show a little over 60 lbs when cold and then about 50 lbs when driving hot. I am using castrol 20w-50 syntec for the first time. When I started it up, it showed 70 lbs at idle, If I rev it up, it went a little over 80 lbs. I didn't drive it or let it warm up all the way ( rainy day ).
Is there such a thing as too high oil pressure ?
Can I damage something with this higher oil pressure ?
Ed
 
High pressure can blow your seals and wash out the bearings. Better get the correct spring for the by-pass and get rid of the nut.
 
About 60 psi cold should be the maximum. Sounds like you were there with the short spring. A stretched spring will just go back to it's original set, as you found. It would need to be annealed, stretched, tempered, & drawn to the correct hardness to have a permanent effect. A new, longer spring would raise the pressure a bit, but I don't think it is needed.

If the spring spacer is too long, it will prevent the relief valve port from uncovering, the spacer can't compress like the spring would, so the spring bottoms out prematurely. The pressure can go very high, as you saw.

The main damage from very high oil pressure on the Healey would be excessive load on the pump drive gear & on it's mating cam gear. It's not a particularly stout drive in the first place.

Secondary problems would be more oil leakage & possibly valve stem flooding. Don't know about "bearing washout", some other engines regularly run at 80 psi or so.
D
 
Thank you both.
I will take the nut out tomorrow and already have a new spring on order.
Ed
:thumbsup:
 
Hello all,

I had an oil pressure relief valve stick on a Triumph six cylinder engine. It blew the oil filter housing off it's seal and dumped a lot of oil. Fortunately I did did no lasting damage.

Alec
 
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