I know this subject has been beat to death but I still need help.
I have been reading posts from other people and taking their responces and applying them to my situation but nothing it panning out.
My problem is with the oil pressure stay too high and have oil all over the engine. I have checked the compression on all cylinders and it's 130. I did a leak down test and I have 10% on three cylinders. My oil plugs are moving freely. The oil level is normal or below. Pressure spikes when the temp goes over 180 degrees.
I have a 69 Baja with the recently rebuilt motor. New cylinders, After market Power Pulley, 110 Engle Cam, 1.25 rocker, oil pump with oil filter, relocated oil cooler and stock crank.
I am trying to give all the information needed to resolve the problem.
OK what is the oil pressure? Where is the oil coming from? The rear crank pulley? Was that "oil slinger" installed on the rear of the crank before the engine was assembled? Stock rear crank pulley? How is the crankcase pressure? Do you need valve covers with breather pipes at their tops going to a collection box at the top of the engine?
Do you have an external thermostat for the oil cooler? These devices look like an "H" with 2 hose coming in, and 2 coming out. These open oil flow to the cooler above 175, and bypass oil cooler bellow that temp. So maybe your oil cooler circuit after the t-stat is blocked, obstructing flow, and raising oil pressure in the circuit before the cooler, or the thermostat is faulty (outlets to the oil cooler not completely drilled or something). Remove and inspect.
What about oil cooler seals? if you have wrong ones or over tighten oil cooler mount that will squish seals too much and restrict the flow as well. Not sure if that would manifest during hot temp more.
ant> Do you have an external thermostat for the oil cooler? These devices look
Look, the oil does not flow to the cooler until it reaches about 180 degrees. If the valve is stuck or a block exists in the cooler system (my guess) the oil cannot cool nor flow properly so the increase in case pressure and damage will happen. Dennis
There is no dog house cooler on the vehicle. It has been moved to where the air flows better. I have the temp gauge on the oil drain plug. The pressure sensor is at the motor.
The oil slinger is installed on the motor. And the after market pulley groove aren't that deep.
One thing that peaked my interest is the squished oil seals to the cooler. If they where squished that might create high oil pressure.
What I should be looking for is a blockage in the oil cooler and/or squished seals?
The seals really make sense because when the engine is cold the pressure is high but it comes back down when it returns to idle.
Also I don't have the tube hooked up from the oil filler to the carb. Might that make some difference in the pressure?
1) Is it a stock oil cooler, relocated, if so it is better off in the stock location. There is no better place for it where it was supposed to be originally. Check the oil cooler seals and oil cooler. Take it to a shop to see if it leaks while you are at it as well. So you are looking for both, restrictions in your oil cooler and crushed seals. Get a new set either way and use correct ones. Over tightening adapter and/or wrong seals can cause blockage and will be destroyed in the process.
2) Not having a hose from oil filler to air filter WILL make oil thrown all over the engine bay. You have to vent your case. If you are running after market air filter or dual carbs. You can get one of those white plastic L shaped fittings that will allow you to vent case properly, ~ $5 a pop plus the cost of ~2 feet of hose.
If you are seeing a fine spray of oil on the blower housing and firewall (ie, 'all over the engine') then you are probably seeing the effect of excessive blow-by or an improperly connected crankcase ventilation system, neither of which has anything to do with your oil pressure.
However, if you are seeing liquid oil dripping off the under-side of the engine then high oil pressure may be a factor.
Which leaves us to wonder about the fourth cylinder :-)
In any case, leak-down testing is also done twice, once 'dry', then again 'wet' (ie, with a squirt of oil DISTRIBUTED in each cylinder). A leak-down test not only determines the amount of leakage but WHERE it occurs (ie, valves or rings)
A ten-percent leak-down is NOT especially good. 15% is often the decision-point for rebuilding the engine.
This would tend to indicate a problem with your oil cooling system, since 180 degrees is about when ALL of you oil is routed through the cooler. If you are using an after-market tube-type oil cooler (ie, 'Rapid-Cool' et al) the spike is probably due to the high restriction of such systems. Or of using hose that is too small. Or the wrong grommets on the adapter. Or a few dozen other things.
I can appreciate that but if you didn't build the engine yourself there will always be a knowledge-gap. Fortunately, engines can't lie and they are more than willing to tell you when they have a problem. The tricky bit is understanding what they are trying to tell us.
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