I'm back again. This time I'm looking to replace the oil pump in my 1984 Z28. It's not broken and oil pressure is an acceptable 25-30psi at hot idle, but if it's not too difficult I'd like to replace the pump with a higher-capacity unit as I'm swapping the cam and heads out and want the lowest chance possible of destroying both. Prodemand gave the useful step one of "remove oil pan," yet it looks like there's plenty in the way of it coming out - mostly the transmission and crossmember, but also the pump and sump.

 

It's no fun at all in these cars.

Best way to do it, is remove the engine. Yeah sounds like alotta work; yeah sounds like it'll take forever; yeah sounds like a pain; but it's nothing compared to what you'll put yourself through trying to lay up under the car and wrangle the pan far enough out to free the pump. And even worse, getting it to all seal back up leak-free the first time (not much fun to have to go through it all over again to fix a leeeeek, no?) when you can't see half of what you're doing and with crap dripping all in your face. One of those situations where you'll do twice the work in trying to get out of doing the work, than the work you're trying to get out of doing.

IMO if it works, best to just leave it alone.

 

Yup, pull the engine.
But if it were me, I'd keep the original pump. No need for a HV or bigger psi pump.

 

If its working any over 15PSI id leave it alone if everything else runs good. But..when its time to replace an oil pump IMO its time to go on and refresh the engine. You pretty much are having to pull it so take the chance to go on and get the motor freshened up.

 

Thanks for the replies, guys. I figured it'd be a ton of work just based on the positioning of the pan; Chrysler likes to pull the same crap. Guess I'll leave the current one in, it was more of a peace-of-mind thing. Someone's borrowing my hoist right now so I can't pull the engine anyway.

 

Not sure about "pull the same crap"; it's kind of inevitable when you jam a motor that just barely fits into a small chassis. You end up with no room around it. It's not like these things have the engine bay height and width of a truck.

 

...yeah, but they did it with a slant six. And then just crammed a massive iron I-beam between the front frame rails right in front of the pan and behind it.

 

You can also pull the engine cradle. That's what I did to get at my pan and took the opportunity to install an UMI K-member and control arms. BEST IDEA EVER! Cured every problem with the front suspension. No more tire scrubbing on full lock turns, no spring popping, and no wandering on the freeway. Rock solid handling.

GD

 

An oil pump should last the life of the motor, so really no need to go through the hassle to change it with the motor in the car.

Different story if you pull the motor for your heads/cam swap, then replace all of the seals, gaskets and go ahead and do the oil pump since it’s easy. In that case, I would probably also pull the main and rod bearing caps to inspect the journal bearings for wear.

 

That was the original plan, unfortunately I don't have the space and my hoist is currently lent out to a friend. As for right now I'm just gonna pull the front clip, radiator, and condenser to get the cam out.

 

I have done a cam swap without taking off the front clip. The radiator and condenser need to come out and the "X" braces that are bolted to the front of the core support need to be moved (should be able to unbolt just the bottom bolts and move them aside just enough to get the cam out). The tricky part was the timing cover/oil pan. You need to loosen the oil pan to get the timing cover off and then bolt the oil pan back on after you put the timing cover back. My oil pan leaked after messing with it.

 

Not to worry, my oil pan already leaks plenty.

 

If you have good oil pressure (implying normal bearing clearances), there isn't any reason to install a larger oil pump on an otherwise stock small block. That stock pump flows plenty of oil. If you put in a high flow pump, you'll just send a lot of extra oil through the bypass and back to the pan. If you have a higher pressure pump, you just add load to the oil pump drive. More oil pressure doesn't necessarily make life better. The key is enough pressure. I wouldn't necessarily put in a larger pump even on a normal rebuild. If you're pushing extreme RPM and need more pressure, fine. If you're running higher clearances or have some other reason for more oil, fine. But "more" isn't always better.