I was wonfering how hard it is to change an oil pump. What is involved and does it require lossening the engine mounts. how long would this take . thanks for any advice.

 

It's a real task. You have to raise the engine (so...yes to your motor mount question) to get the oil pan removed and clear. Oil will be dripping from everywhere, making work down there really fun. Removing the distributor to keep it from hitting the firewall during lifting is a good idea.

For the new oil pump, you'll want to fit the pickup to be 3/8"-1/2" from the floor of the oil pan. Welding the pickup to the pump base is recommended, but there are bolt-on straps now that accomplish the same thing.

If you're trying to treat low oil pressure, swapping pumps is not likely to do much. Bearing clearances at the crank contribute to much of what you see on the pressure gauge.

 

Kevin is right. Oil pumps almost never go bad. There's no point in taking apart an engine just for that.

Why are you considering doing this?