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General Tech Oil Pressure

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KVH

KVH

Obi Wan
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After driving for about 45 minutes and idling at several stoplights yesterday, I noticed that my oil pressure, at idle, was only about 30 psi. While accelerating it goes up to about 70 and while ordinary driving, it’s around 55 to 60 psi. Does this sound OKAY?
 
Sounds OK to me at first view. What is your idle speed? I keep mine down around 700 RPM to prevent dieseling when I shut the engine off, and the oil pressure at idle is about 35 PSI, plus or minus a bit.
 
It's a little lower than mine, but I have a new engine (4000 miles on the rebuild) so it's probably still fairly tight, compared to others. In any case, your sounds OK to me.
 
More than 70 is excessive. 30psi at a hot idle is very nice( IMHO) as 20 is the more common reading in most cars.
Mad dog
 
Thanks guys. Just fyi, I run 20/50 oil, and it was a hot day when it read 30 psi. Engine is new. Maybe 3500 miles. It runs great. Roars!
 
Years ago we rebuilt a Tr4 motor that had had the pressure relief valve adjusted for the old worn bearings.
Never got the chance to re-adjust it before the gage exploded in a spray of oil ,on start up.
In retrospect I would say that backing off the valve a bit for the startup procedure of spinning the motor
(sans sparkplugs) until the pressure is up, would have been better.
Mad dog
 
Sounds pretty normal for these engines. I run 20w50 in mine. On cold start I run about 50-60psi. When it is fully warm, it runs about 50psi going down the road. At idle, warm, it depends on the weather, but about 25-30 is normal. These engines are kind of old fashion. Oil volume is more important than pressure, but you still have to have enough pressure to keep everything moving. Summer weather here in the California desert brings ambient air temps. well over 100deg. I usually set my idle speed up a little in the summer to play it safe. I also use a little higher octane fuel in the summer. ...J.D.
 
KVH said:
How does one adjust that pressure valve.
Click to expand...
On the oil filter head there is a bolt with a locking nut. You loosen the nut and adjust the bolt inward for higher presser, and outward for lower. Then retighten the lock nut. It's really that simple! The only "but"...if the adjuster bolt leaks after the adjustment, it is sealed by a couple wraps of lead wire. Normally it will remain a good seal, but if not, then you will have to remove the nut and wrap a fresh wrap or two of lead wire (or thin electrical solder) around the adjuster and re-tighten the lock nut.

You adjust for 65-70psi on a warmed engine with RPM above 2000. Idle and initial start cold pressures are whatever you get, and don't worry about it unless it is zero. That is a sign that you have a wear or mechanical problem.
 
CJD said:
On the oil filter head there is a bolt with a locking nut. You loosen the nut and adjust the bolt inward for higher presser, and outward for lower. Then retighten the lock nut. It's really that simple! The only "but"...if the adjuster bolt leaks after the adjustment, it is sealed by a couple wraps of lead wire. Normally it will remain a good seal, but if not, then you will have to remove the nut and wrap a fresh wrap or two of lead wire (or thin electrical solder) around the adjuster and re-tighten the lock nut.

You adjust for 65-70psi on a warmed engine with RPM above 2000. Idle and initial start cold pressures are whatever you get, and don't worry about it unless it is zero. That is a sign that you have a wear or mechanical problem.
Click to expand...
OKAY. Great. Thanks.
 
These engines have a pressure relief spring and plunger in the left side of the block. When I bought mine, I had some fear the plunger was stuck. Someone has been into this engine before me. It looks like it has been at least partially rebuilt. It had been sitting for some time as well. The previous owner had pass away. The head has been painted a different color than the block. So has the oil pan. The rocker arms etc. were very clean when I adjusted it's valves. The oil pressure always stayed very high. After I changed the oil, I installed a spin on filter kit, and ran it a few hundred miles, and the pressure is acting more normal. I have purchased a new pressure relief kit from British Parts Northwest. I plan to change that out during my next oil change just to be safe. ...J.D.
 
On my TR3A, the oil pressure adjustment was originally sealed with a lead washer under the nut (Standard Triumph part 30123 in the spare parts catalogue). The washer is NLA at any of the suppliers I checked.

This winter, I replaced the spring and ball in the oil pressure valve to address an oil pressure that I considered too high.
On disassembly, the lead washer crumbled as it had perished, somehow, though it had not leaked.
Perhaps solder wire wrapped around the thread would have worked, however I gently hammered a piece of scrap lead to washer-thickness. I drilled and then punched a washer out of it using a die from a set that I have for making bolt-holes in gaskets. A small fishing weight would be plenty of material for this and it only takes a few minutes.
 
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