Oil pressure

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scott75
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Oil pressure

Post by scott75 »

Hi all
i have just fitted a oil pressure gauge and the engine is sitting at or around 40lbs at tickover and climbs too 60ish as i rev up.
This is on a standard 1098 engine.
Are these pressures ok and what is a good safe running temp for the engine? again many thanks .



SCOTT
turbominor
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Post by turbominor »

sound like a nice health engine if it is doing 40psi at idle when hot?

Temperatures depent on the engine but i get 90-100deg as the thermostat opens at 88deg on mine.

Normal temp to open is 82deg??
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Willie
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pressure

Post by Willie »

If your tickover speed is normal then 40 psi is excellent. The
pressure at 30 mph upwards in top gear, hot, should be steady
on 60 lbs. The only time the pressure ever goes above 60 psi
should be when the oil is cold. those figures are for a top
condition engine but the A series will work fine with much lower
pressures. If the pressure running hot is way above 60 you need
to fit the correct length spring in the pressure relief valve (to the rear of
the distributor).
Willie
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scott75
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oil pressure

Post by scott75 »

Hi all although the pressure reads 40lbs at tickover this is when the engine is starting from cold.
When the engine heats fully the pressure at tickover is lower about 25lbs doe's this mean i have a problem as the engine is a recon that has done less than 2000 miles?
This is on a mechanical gauge could there be any other reason for the drop in pressure rather than a worn engine? many thanks

SCOTT
salty_monk
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Post by salty_monk »

I wouldn't worry about 25psi at tickover as long as it climbs with the revs when you blip the throttle... As Willie has said, most engines will run at a lot lower than ideal pressureanyway but yours sounds healthy enough...
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scott75
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Post by scott75 »

Cheers Salty reasurance was required now all i need do is sus out my vaccum gauge lol
Willie
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pressure

Post by Willie »

I too had a 'completely reconditioned' engine but when I fitted
an oil pressure gauge I discovered that the oil pressure was lower
than it should have been. eventually I fitted a new oil pump and the
result was excellent i.e. the 'experts' had not fitted a new one during
the recon. With your engine does the pressure reach 60 psi
if you rev up when the engine is cold? If the pressure never reaches
60psi then it is worth replacing the spring in the Oil Pressure Relief
Valve because it is the easiest thing to try. This spring controls the
MAXIMUM pressure in the engine and MUST be 2. 55/64" long(
that is two and 55/64 inches). If your spring is shorter then it
could be preventing the higher reading from being attained. The
spring is obtainable from Minor specialists and is to be found under
the domed nut to the rear of the distributor below the oil pipe union.
You have to remove the starter motor in order to get a socket on
the domed nut. DO NOT increase the springs length to more than
the stipulated length in an effort to increase the pressure, you only
need 60 max HOT. If you cannot attain that figure then it is down to
a poor oil pump or worn mains/big ends i'm afraid.
Willie
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MikeNash
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Post by MikeNash »

I see Turbominor gets a 90-100C reading with his 88C thermostat. I use one of those but I only get a reading of 75-80C this time of year. I'm using a Smith's bulb type gauge which I've checked and found to be accurate to within 1-2C. The thermostat also opens spot on. The only way I get high water temps is to blank off the radiator. Before I get the thermostat out again to check it, do you think the waterpump might be chucking some of the radiator return up toward the thermostat? Mystified.
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