Replacing Chevy 350 engine suggestions?

gussie

Cadet
Joined
Aug 26, 2008
Messages
19
It looks like we have to replace the 350 engine in my son?s 22ft BW Revenge. We can buy a brand new Chevy 350 with 4 bolt main, 2 pc rear seal engine for $1563.00 in stock locally. All the other things should fit on this engine since it is the same as the old one, we hope. This, of course, is not a marine engine, thus no warranty.

What if we were to replace the seals and gaskets ( especially head ), the cam, and freeze plugs? All the other parts, like carb, fuel pump, starter, alt, are marine. What do you think about this approach to solving our re-power dilemma?

The boat is used about 3-4 times a month from April to September for fishing in brackish water, and usually not run continually, except for trolling for 6 weeks in the spring.

Are we to be concerned about longevity, or cracking a piston, throwing a rod, or other internal engine damage?
Your input will be greatly appreciated. Thanks!
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,464
Re: Replacing Chevy 350 engine suggestions?

We can buy a brand new Chevy 350 with 4 bolt main, 2 pc rear seal engine for $1563.00 in stock locally.

Ayuh,....

You can pretty much just dress that truck motor with the Merc. components from your take-out motor,+ Go Boatin'...

Last I knew the GM crate motors are spec.ed for trucks,+ have composite headgaskets,+ brass coreplugs...
The Cam,+ other internal components are a Non-issue...
 

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Replacing Chevy 350 engine suggestions?

Thats a good price also, yep it's doable. And the easiest way to go.

How old are the manifolds and risers another 500 bucks you can have new ones
with gaskets and everything ready to install. All in one box, something you should consider.

Good luck !
 

abj87

Petty Officer 1st Class
Joined
Aug 4, 2008
Messages
354
Re: Replacing Chevy 350 engine suggestions?

Cant beat a new engine from gm for reman prices. They probably wont honor the warranty though.
 

slasmith1

Lieutenant Junior Grade
Joined
Dec 2, 2008
Messages
1,028
Re: Replacing Chevy 350 engine suggestions?

If most or all of your boating is in brackish or salt now is also the time to add a fresh water cooling system (heat exchanger)
 

mylesm260

Chief Petty Officer
Joined
Sep 13, 2007
Messages
444
Re: Replacing Chevy 350 engine suggestions?

I will echo what he said.

Heat exchanger based cooling is definitly the way to go. Protect your engine from corosion and potential freezing. Let your exchanger take all the risk and abuse.
 

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Replacing Chevy 350 engine suggestions?

My boat is 23 years old saltwater used, still the same original manifold. Has a 22 year old saltwater used motor in it, If you flush every time you come off the water no reason why your new motor won't last that long.

Point is i don't have the heat exchanger, a lot of boats don't have it.

Why the old motor coming out may i ask, freeze damage??

Really to many things go wrong with those fresh water heat exchangers, and they clog. They leak, i don't like them.

Do a search for yourself on this forum make up your own mind.

Good luck !
 

abj87

Petty Officer 1st Class
Joined
Aug 4, 2008
Messages
354
Re: Replacing Chevy 350 engine suggestions?

I tend to like closed cooling systems even in freshwater. With a heat exchanger you can run the engine at a more efficient hotter temp. 180 vs 160 . In addition its pressurized which increases the boil over temp.
If you get a kit that includes the manifolds in the system they will last for the life of the engine.
Instead of running corrosive sea water though your expensive engine you run it though a nickel-copper heat exchanger which is naturally corrosion resistant and anti marine growth.
I have never had any trouble with any of mine clogging up, but your in an area with more marine growth. (over 1500hrs done nothing to the cooling system,other than impellers)
I'm just bias against raw water coolings systems i have had nothing but trouble with them.
 

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Replacing Chevy 350 engine suggestions?

In fresh water nobody needs a heat exchanger, period the boat will last longer then the owner.

Saltwater is the where it would be needed and thats the debate.

Just my 2 cents.
 

abj87

Petty Officer 1st Class
Joined
Aug 4, 2008
Messages
354
Re: Replacing Chevy 350 engine suggestions?

In fresh water nobody needs a heat exchanger, period the boat will last longer then the owner.

Saltwater is the where it would be needed and thats the debate.

Just my 2 cents.

Were i boat its silty so it keeps it out of the block and manifolds, cuts down on corrosion even in freshwater and makes winterizing a breeze. Everyone is has there own opinion though.
 

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Replacing Chevy 350 engine suggestions?

Abj is 100 percent correct, you have valid points and people do use the heat exchanger.
 

betayv

Senior Chief Petty Officer
Joined
May 13, 2008
Messages
706
Re: Replacing Chevy 350 engine suggestions?

hi there this mean a 350 marine engine is the same as a automotive engine thanks.
 

mylesm260

Chief Petty Officer
Joined
Sep 13, 2007
Messages
444
Re: Replacing Chevy 350 engine suggestions?

Heat exchangers take less time to flush aswell...

IF you have a heat exchanger, you connect your muff's turn on your water, start your engine, let it idle for 30 seconds and your done.

If you don't have a heat exchanger, you have to wait until your engine reaches 160 degrees for your theromstat to open, otherwise the water won't actually be circulating through the block.

I know this isn't really that big of a deal, but it's the difference bettween letting your engine run for 30 seconds at the end of the day or 5-10 minutes.
 

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Replacing Chevy 350 engine suggestions?

beta have you been reading the thread??
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,464
Re: Replacing Chevy 350 engine suggestions?

hi there this mean a 350 marine engine is the same as a automotive engine thanks.

Ayuh,... Where does it say that Anywhere in this thread,..??
 

gussie

Cadet
Joined
Aug 26, 2008
Messages
19
Re: Replacing Chevy 350 engine suggestions?

Thank you all very much for your input. I think the issue of whether to replace the raw water manifolds and risers, or switch to fresh water exchanger will come later.

The reason to replace the engine is a long story. The boat was purchased knowing that the engine was very questionable. It is mainly centered around the fact that the cylinder bores are pitted, and the engine has already been rebuilt by previous owner.

The main issue was whether this new Chevy truck engine can be used in a boat without any serious problems, if we use all the marine parts from the old engine.. Thank you Bond-o for your opinion. So, you think it will be just fine?
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,589
Re: Replacing Chevy 350 engine suggestions?

Here we go again, these threads are as bad as the 2 cycle oil threads:rolleyes: I myself always install a marine spec engine as being taught thru Mercruiser service school there are MAJOR differences between auto/truck spec's and marine. Also the engines I install come with a 2 year warranty and will pay you $50.00 hr up to $550.00 for failure or problems with engine(none so far). I also have seen the Autozone/Napa/Carquest and Gm crate engine state no warranty if used in marine applacations. Do what you want this is just my opinion ;)
 

betayv

Senior Chief Petty Officer
Joined
May 13, 2008
Messages
706
Re: Replacing Chevy 350 engine suggestions?

I agree with Faztbullet but someone can explain to me and Im sorry for being ignorant but internally the marine engine will be the same as automotive thanks.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Replacing Chevy 350 engine suggestions?

betayv
If you have a question, start a new thread about it. Don't hijack someone elses question with things you don't understand.
You can use this one as a reference, to your question, but asking in this thread is just plain confusing to everyone trying to figure out who is answering which post.
 

betayv

Senior Chief Petty Officer
Joined
May 13, 2008
Messages
706
Re: Replacing Chevy 350 engine suggestions?

Im sorry thanks.
 
Top