Thermostat and oil pressure-- All fixed

[geopig]

Does anyone know the torq spec for a pinion nut on a dana 35

Hi again,

So I recently posted at thread regarding my heater core and coolant leak issues. See it here:

http://www.jeepz.com/index.php?name...t=323610&sid=d87c753c8ceff344c0f5a48c6e5f714e

So I replaced the heater core and hooked everything back up with new hoses. Also did a cooling system flush while I was at it.

When I started back up the engine got hot, quick but there was no heat coming from the heater and when I checked the upper radiator hose it wasn't hot either. Now this seems like a thermostat problem. However, I also noticed that my oil pressure was high and actually got so high that it buried the needle on the gauge (>80). Could there be some relation there? Or is it possible I did some engine damage when I was driving home with the leak. Other than the engine periodically getting hot the oil pressure was normal during the period when I was driving with the leak. Also I checked the oil and it was fine. Furthermore, when I filled up the radiator after replacing the heater core and hoses, it only took 1 gallon of coolant and about 1/4 gallon of distilled water. Could there be air in the system that could be causing the problems?

Thanks again for the help/advice in advance.

 

[LBR]

Yes - your block wasn't completely full of water and created steam, which is hotter than water but won't register properly on the temp gauge and cooler than normal upper hose to the touch (no coolant circulation) - after a coolant purge, I always run the engine a couple of minutes while monitoring the water level, then shut it off. As the heat saturates the block, heads etc., the thermostat will many times open up without the engine running. Then fire it, top off the level, drive a few miles to purge all head coolant pockets and top off again (whew! lots 'o work!) LBR

 

[geopig]

Could this situation be the cause of the high oil pressure as well? Thx LBR.

 

[LBR]

there are not many things that can happen in an engine to create a higher than normal oil pressure, especially in an "all of a sudden" situation like you described. Usually when you overheat and do any damage to an engine, the pressure will be less rather than more - did any other events in that time frame happen that might spread some light on this?

 

[geopig]

No not really, and I didn't ever really "overheat", I was loosing coolant and getting hotter than normal, but the couple times I stopped and checked there was still coolant present when I refilled. When I finally got home the oil pressure was normal, and between then and this afternoon, I haven't fired up the jeep, just been replacing the heater core and the heater core hoses. Nothing else really happened.

Hmm, just wondering if something could have gotten clogged when I was loosing coolant inside the engine compartment that may be affecting the oil pressure?? Its the only thing I can think of right now.

Also, I ran the engine for a couple of minutes and the coolant level didn't drop in the rad. Took it out for a quick spin, made it less than 1/2 mile before engine was getting way hotter than normal operating temps and the oil pressure gauge was buried. Should I run the engine with the radiator cap off to release the air? Or maybe I'll try purging the system again.

More advice will be greatly appreciated. Looks like I'll be riding my bike until this gets sorted!!

 

[geopig]

So I have an update and still am having problems. I don't know if they are related or not but I've got 2 problems.

The first is the cooling system not functioning properly. I replaced the heater core and hoses flushed the rad. and now the engine is getting hot very quick but the coolant is not (see above for more detail). Here is the update. When I run the engine for a couple of minutes and then open the radiator cap there is pressure there and coolant overflows from the cap but it is not hot at all, not even warm. So I drained the rad. again this morning and refilled (just with water at this point) and the same thing is happening. It sounds like the thermostat but could it be the water pump (I hope not)?

The second thing is still the oil pressure. It gets sky high after running the engine for a couple of minutes (buries the needle on the gauge) which makes me very nervous. Any ideas what the problem could be there and if it is possible that the two issues are related.

Sorry for the lack of new info but I'm kinda stumped as to what to do next.

P.S. Prior to the heater hose leaking on Sunday everything was fine with the oil pressure typically 40 psi at idle and 60 psi when engine cold.

 

[geopig]

So I replaced the thermostat and the cooling system seems to be functioning properly now, along with the new heater core. Temperature climbs normally and the heat works. However, I'm still getting really high oil pressure. The needle buries after just a few minutes of running. Any thoughts?? I may have to take this into someone to get it fixed, I think I'm getting over my head, but any suggestions are appreciated.

Cheers,
Geoff

 

[Ford_Dodger]

Have you considered the oil pressure sending unit? It may be faulty. Coincidental cuz of the cooling problem, but it might be shot... The gauge would become eratic if the sending unit failed.

 

[Ford_Dodger]

P.S. - If it is the sending unit, you might consider a manual oil pressure gauge with copper tubing. Much more accurate than an electrical sending unit. I am installing mine this weekend cuz my sending unit is shot and my gauge reads 60-80 psi!

 

[geopig]

I'm back in business. Thanks for all the advice. Replaced the oil pressure sending unit and all is well with the cooling system and the oil pressure.

 

[LBR]

Keep a close eye on it GP - if it happens again, it could be a dropping resistor for those gauges - I don't know if this advice is applicable to your Jeep, but I had a 1977 Mercury Capri w/ the 2.8 L engine - had this particular problem - 2 of my 4 electrical gauges would freak out at exactly the same time - turned out to be a very, VERY intermittant voltage spike (through a faulty dropping resistor in back of dash) - the clue was both did the same raise/lower dance at the exact same time.... Good luck LBR

 

[geopig]

Thanks for the tip LBR, I'll keep my eye on it. Cheers.