Replacing camshaft bearings while engine installed?

Question

I have a 1987 boat with twin crusader (chevy) small blocks. My oil pressure on one engine dropped from 25-35 psi @ 2500+ RPM to less than 10 psi. I also have a metal to metal bearing noise in the top front of my engine. I assume I lost the front cam bearing. If I pull the cam and I have a bad cam bearing, can I replace it without removing the engine?

I have installed cam bearings in a bare block before, but have never removed them. I guess I'll have to remove the oil pan to get the bearings out once I drive them out of the journals?

Can I just knock the old bearings out and drive new ones in?

I know I'll be replacing the cam and lifters along with the bearings.

This is in a 34' boat and for me to pull the engine I will have to get it out of the water and blocked. It will cost over 500.00 just to do that plus storage by the day. I am hoping I can do this in the boat while tied up in my slip.

Thanks in advance

Answer 1

yes you can be sure and remove all of the bearings. also remove your rod bearing caps to See if any one have spun and broke the tabs. that will also cause low oil pressure.

Answer 2

No cheap way out >If you have metal in the oil the engine need to be completely torn down and flushed out or the bearings & crank shaft will tear up> Might be less money to find a short or long block replacement>The cam shaft bearings have to be pressed in & line bored for aliement>

Answer 3

Maybe you can do it in place, but it will make a mess.  Many engines can be pulled without drydocking. Ask your local repair yards and try Craigs list for local marine engine mechanics. Get many references if you go with an unknown mechanic.