Rebuilding A Mercruiser 5.7?

[raptrax]

Hey guys I'm new to the forum and new to owning a boat. i just picked up a 1987 Sea Ray Sorrento 5.7 mercruiser but the engine is seized and it looks like I'm going to be rebuilding. Can any of you guys point me in the right direction as to where I can pick up a rebuild kit gaskets, pistons, bearings etc.

I'll be pulling the motor out and ripping her apart to see what I'm getting myself into this weekend but just want to do my research first.

If you guys have any suggestions I would appreciate it!!!

 

[Fun Times]

Re: Rebuilding A Mercruiser 5.7?

Here is one of many places to come. Good luck with it.

http://www.mercruiserparts.com/selectModels3.asp?type_id=8

 

[raptrax]

Re: Rebuilding A Mercruiser 5.7?

Nice, looks like it's gonna be fun! Don't flame me now I'm a newb how interchangeable are automotive parts for the 350. I guess what I'm trying to say is can i order a automotive rebuild kit from like jegs or summit racing (gaskets, cam, pistons and assembly, bearings) and be safe? Or the rebuild has to be all marine parts?

Sorry for the newb questions?

 

[toolsinbox]

Re: Rebuilding A Mercruiser 5.7?

a few points here.
If your going to re-build it is crutial to get the service manual, read and understand fully how all the components work and what they are for. It won't take you long to realize that there are very unique parts that differ from auto engines. From the materials used to the way an engine computer is programed. I can't stress enough to read and understand all before buying parts as it will save you time and money in the long run. For example; to your question; marine engines use spicfic types of head gaskets. If you bought a auto re-build kit you may not have the correct one.

There are going to be quite a few part options for you to decide as far as quality, manufacturers, and price. A full understanding of a marine engine will help you make the best choice. The four key considerations are type of boat; what are you going to use it for; salt water or fresh water use, And is it going to sit in the water for long periods or be a trailer queen. Maybe a combination of these. you need to prepare your engine for these factors and several more.

A marine engine most closely relates to a truck engine. If budget and/or time is an issue, then they can work well but external parts must be swaped or purchased.

The last point I will make is; using certain auto components can be against boating regulations and void any insurance policy in place, but most importantly It can, has been, and will be deadly to people.

Just saying.

 

[raptrax]

Re: Rebuilding A Mercruiser 5.7?

Toolsinbox thanks for all the info I just ordered the repair manual... The motor is bone stock from the factory mercruiser 5.7 so all the parts on it are for marine use.
The boat is going to be mainly a fresh water boat with occasional salt water trips to Catalina. Yeah I read that pretty much all the gaskets have to be marine gaskets, brass freeze plugs, marine alternator,dist and anything that produces a spark (I don't want to blow up and hurt anyone).

Im just rebuilding the internals freshening it up!

Any other wise tips would be greatly appreciated...

Here's a pic of the boat I just picked it up! Needs a little detail!!!

 

[fishaman]

Re: Rebuilding A Mercruiser 5.7?

The main question is whether the engine is fresh water cooled, in this case the block had never seen salt water, and may be rebuildable. Otherwise, the engine is raw water cooled with salt in the block... I would not even think about rebuilding a 23 year old seized saltwater engine, it makes much more sense to start with a compatible auto block.

 

[Silvertip]

Re: Rebuilding A Mercruiser 5.7?

Correction: Start with a TRUCK block. The cam in a truck is far more suited to marine use than a car.

 

[raptrax]

Re: Rebuilding A Mercruiser 5.7?

Well i couldn't really tell you if it's been in salt water. The engine has a total of 168 hours on the clock. The guy I bought it from inherited it somehow some way and it's been sitting for 15 years.

When I rip it apart is there any way of telling if the engine has been in salt water or not?

 

[John_S]

Re: Rebuilding A Mercruiser 5.7?

Tear it down and find out why it seized, and how bad the rust is. Could have been freeze damage, cracked block, heads, etc. Once you know what you are dealing with, then decide if it is rebuild or new long-block.

BTW, boat looks nice and like the older style lines.

 

[raptrax]

Re: Rebuilding A Mercruiser 5.7?

Thanks imported_John_S I will hopefully have an update this weekend on what my next move is.

And thanks for the compliments on the boat...

I love the lines too! I scored on the boat it's practically brand new minus the motor. Can't wait to get her back up and running and in the water.