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Discussion Starter #1
Well, I got my oil pump installed and the rig is going back together fairly well. I still have to lower the engine and put the tranny and motor mount bolts back in as well as tighten a few things but, I should be able to fire up the engine soon.

One thing worries me though is the oil pump drive shaft. It went right in! I was working with the pan just dropped and not out completely. From what I hear and read on these forums, that kind of easy just don't happen.

I plan to let it crank over nice and slow a few times to ensure my pump prime worked. Is there any certain type of sound I might hear if I got the oil pump drive shaft in the wrong hole or something really dumb like that? :whiteflag
 

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But the special little tool to prime your engine. You stick it in the disbutor hole, spin it with a drill and it primes everything up nice.. you can probably even turn your acc. key on to see your pressure.

Thats what I did with my new engine and it was happy as could be, when I fired it.
 

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Discussion Starter #4
Thanks guys. I went ahead and fired it up before any responses showed. Oil pressure on a cold engine jumped right up to 50 or so on my mechanical gauge.

I was real happy until it warmed up and the oil thickened...pressure about 4PSI at idle!!!! Pressure at 1700 RPM going down the road is about 11PSI when the oil is good and hot.

Gonna try a few other tricks later on to see if I can't flush out those crappy oil passages!
 

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"I was real happy until it warmed up and the oil thickened"...Just the opposite it gets thinner as it gets warmer hence the low O P ..
 

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Discussion Starter #6

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Thanks guys. I went ahead and fired it up before any responses showed. Oil pressure on a cold engine jumped right up to 50 or so on my mechanical gauge.

I was real happy until it warmed up and the oil thickened...pressure about 4PSI at idle!!!! Pressure at 1700 RPM going down the road is about 11PSI when the oil is good and hot.

Gonna try a few other tricks later on to see if I can't flush out those crappy oil passages!
Before wasting money on "flushing", you should know that a restriction in an oil passage on the outlet-side of the pump INCREASES pressure. A DECREASE in pressure is caused by less than a "normal restriction (as you get with worn bearings).
In other words, you're barking up the wrong tree.
You DID check your bearings while the pan/pump were off, eh?

DGW
 

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Discussion Starter #8
Before wasting money on "flushing", you should know that a restriction in an oil passage on the outlet-side of the pump INCREASES pressure. A DECREASE in pressure is caused by less than a "normal restriction (as you get with worn bearings).
In other words, you're barking up the wrong tree.
You DID check your bearings while the pan/pump were off, eh?

DGW
Absolutely! If the oil pressure were bad or pretty marginal from start up, those bearings would be my prime suspect without a doubt.

I never managed to get the pan all the way off. Just dropped it far enough to get to the pump and pickup tube so I didn't check out the bearings clearances. I know I should have taken the time and effort but just getting that far had me frustrated that I just wanted to get the pump done and button it back up.

One thing I read here is that the oil return passages may be restricted and that could cause a low oil level in the pan resulting in low pressure...not at all sure if that is going on or not.

By the time you responded, I had already dumped some flush into the oil so I'll give it a shot for now. Fired up the rig with the flush in it this morning. Starting pressure was about 50 PSI. As the engine warmed, pressure dropped steadily and I shut it down when the pressure was at about 14 PSI.

It could also be that as the engine warms, the engine parts expand and THAT causes excess clearances thus dropping pressure.

Oh well, experimentation gives me first hand observations...in the mean time, saving for rebuilt engine!:whiteflag
 

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