I am currently experienceing what I believe is an oil pump problem with an '88 Bronco, 302 v8 with 122k miles.

I just bought the vehicle from an auction, it's in pretty bad condition, but it's almost back to a good running state (replaced several things from an ECT sensor to a cracked manifold). After those and some other repairs, the vehicle is running a lot better, but still not running all that great.

The following problems are most evident right now:

-It gets REALLY hot REALLY fast. After starting it, not even a mintue later the exhaust manifold is too hot to touch
-At idle (right now its idling at about 600 RPM when warmed up), the oil pressure gague (this is the dash gague, I haven't checked it with a shop gauge) goes to zero and the "Engine" light comes on, but then returns to normal presssure when RPM is over 2000 and the light goes off.
-Once the engine is hot, if you let it sit at idle for a few mintues it will start to smoke out the exhaust manifolds and buck like it has no oil (when it has a full oil level)
-It's running a little rough and failing emissions with high HC (possibly because it's so hot i'm getting a pre-ignition?)

...okay, so it obviously is having some kind of oil problem. It would be really nice if all I had to do was do a flush out the engine and then replace the oil pump and screen, etc...

However, when I changed the oil it was blacker than night, and the filter felt like it had a brick in it. I'm afraid that the engine has been run in this condition for a long amount of time by the previous owner, and that an engine rebuild may be in order.

Any thoughts about this would help, specifically I'm looking to see how probable it is that the engine is seriously damanged and needing a rebuild, and any recommendations for getting the oil pressure back to normal.

Also, if someone knows how to check the pressure with a shop gauge that would be grealy appreciated.

Thanks,
Robert

 

I had the same problem on my '88 351w. The oil pump screen was clogged up and took the mains with it.

All I did was replace the crank, main and rod bearings. Oil pressure is 65-70 cold and 50 hot driving. 25-30 hot idle. Not to bad for $700. ($300 for crank. oil pump, bearings, gaskets, fluids, filters, and $400 even to pull engine. replace parts and put it back in)

To check the oil pressure, get a guage from walmart for $10. Remove the stock oil pressure sender and install the guage per the instructions. Start engine, read gauge at 4 stages. Cold idle, hot Idle in park, hot idlle in gear, and hot cruising. If the hot idle is less than 10 psi, you have problems, likewise if the crusing PSI is less than 10 psi per 1000 rpm, the bearings are shot.

Good luck.

 

Thanks for the info, I'm going to pull the oil pan soon (probably not till next weekend though) so that will give me a chance to check out the camshaft bearings and whatnot. Did you replace the main's yourself? I was looking through the manual and it was kind of vauge on the procedure, if you've done it and have any useful tips that would be appreciated.

I did run into walmart to look for the gauge, but didn't see one (but i only had a minute so I may have missed it). Is there a specific name/brand I should be looking for?

Again, thanks for the info.

Robert