302 stiitng up for 20 years...where to start

[Fatbs]

I just picked up a 70's model 188hp mercruiser with the 302. It has been sitting up for 20 years. I know that the part exhaust manifold is cranked. what should i do to prevent any damage before i start trying to start the motor? This will be a project so i will be asking many questions and updating progress.

 

[Fishermark]

If your manifold is cracked I would be very suspicious of the engine block as well. They usually crack because water was left in them and it froze and cracked the metal. If the manifold had water, then the engine did too. Before spending any money on fixing or replacing anything it would be a good idea to see what else it broken.

Then, if it works out, you can start with the basics of oil change and tune up on the engine. And an oil change (and pressure test) and impeller replacement on the drive.

Pull the drive and check engine alignment - replace the bellows - and anything rubber... the list is getting long!

 

[Scott Danforth]

If a manifold is cracked, it is an indication of possible engine damage like Jerry stated.

Start by doing a pressur test, and then a compression and leakdown test

 

[Fatbs]

Okay. Got the boat from my brother. I am sure nothing him he drain everything but the port manifold.