I just had the motor worked on in my '91 Bronco (5.0). Had new lifters, rods, cam done, however, now when the truck warms up, it loses oil pressure at idle in gear; also starts hard (turns over hard) when its warm. Other than these problems it runs like a bear.

What bothers me is that before I has this work done, although it ran like caca, I didn't have either of theses problems...

 

The oil pressure could be the sending unit. I had to replace mine about 3 days after replacing the motor. (They missed the sending unit and used the old one). For the starting, make sure they put the heat shield back on with the starter. When the starter gets too warm, it will have problems starting. It sits right by the exhaust manifold. I would go to the solenoid, but from what you said, it only happens when warm, so I would go to the starter. If it hasn't been cooked too bad you should be OK. Otherwise you may need a new starter.

 

thanks, that what my mechanic was saying about the starter...by the sending unit, are you talking about the guage sending unit ?

If the heat shield is gone, and ideas on what its supposed to look like so I can fab one up ?

 

The Oil sending unit. Attaches to the block. If you have any knocking then it will be something else. If no knocking, the probably the sending unit.

The shield is kind of a half moon bend to it. About the same length of the starter with a couple of tabs that are secured by the starter mounting bolts.

 

A suggestion if you find it necessary to repace the sending unit for the oil gauge, just buy a mechanical gauge setup and install it instead. The factory electronic gauge/sending unit is nothing more than a glorified pressure switch which will indicate "good" oil pressure with as little as 5 psi which is of course NOT GOOD.