Can I replace my short block with 305 chevy?

[vampirefish]

Well.. my engine is cracked (Mercruiser A1, Gen II, 5.0 V8 Inboard) so I need a new one (old thread - http://forums.iboats.com/showthread.php?t=395665)

My cousin (mechanic) is interested in helping me out with this engine so I have a question... can I swap out with a Chevy 305 short block? Will any of this engine work at all? He said he wasn't sure if the crank would work (said he had a friend try that once and it didn't but can't remember what type of engine his friend had - of course he said we'd know once we pulled mine out of the boat... but I'm trying to do some homework here).

305 Chevy short blocks I'm finding are CHEAP. So I'm thinking that if I can save any money, why not do this? Thoughts? Any experience with this? What could I use from the engine if I can do this...?

 

[RogersJetboat454]

Re: Can I replace my short block with 305 chevy?

You may be able to use a short block. Providing your heads are in good shape. With the freeze damage that happened to your block I would have the heads thoroughly inspected by a machine shop to check out what kind of shape they are in. Any cracks or excessive corrosion will mean you need new heads. On top of that, if your old heads are any good, they probably need a rebuild. Heads surfaced, valves reground, new valve seals, valve springs checked. In the end you would probably be looking at 4-500 bucks for a good once over to the heads.

What do you intend on using for a short block? Something out of a car or truck, especially high mileage is only going to be a band-aid fix before it wears out. Unless you intend on doing a complete rebuilt to the lower end of a used short block, or at the very least a fresh set of bearings, and an oil pump, you will be on borrowed time.

As far as the crank is concerned, your cousin needs to figure out if the engine in your boat is a 2 piece or 1 piece rear main seal. Then find a matching replacement engine.

Have you looked into the cost of a reman long block at all? By the time you are done patching together a 305 for temporary use, you may be close to the cost of a remaned 350.

 

[vampirefish]

Re: Can I replace my short block with 305 chevy?

Thanks... I guess I can also look here.... buy something with the heads... ?

http://www.rapidomarine.com/default.aspx?p=/engines/default.aspx

maybe that will just the be the best bet... but I guess we'll just have to get the engine out first.

 

[Bondo]

Re: Can I replace my short block with 305 chevy?

buy something with the heads... ?

Ayuh,.... Buy a 350 long Block,.... It's like Free Horsepower when dealing with a Dead 305...

 

[vampirefish]

Re: Can I replace my short block with 305 chevy?

Ayuh,.... Buy a 350 long Block,.... It's like Free Horsepower when dealing with a Dead 305...

That's what my cousin said... but wouldn't I need to replace the lower end too?

 

[Bondo]

Re: Can I replace my short block with 305 chevy?

but wouldn't I need to replace the lower end too?

Ayuh,... lower end of What,..??

V8s usually all run 1.50:1 geared outdrives...

 

[Matt89GT]

Re: Can I replace my short block with 305 chevy?

Ayuh,.... Buy a 350 long Block,.... It's like Free Horsepower when dealing with a Dead 305...

there's no replacement for displacement

 

[vampirefish]

Re: Can I replace my short block with 305 chevy?

Ok, ok... I just recall reading on this forum (somewhere) that if you upgrade the engine you need to upgrade something else, but I'm obviously mistaken