Rebuilding a 1997 5,7 - mix of parts Vortec/non Vortec, help please!

[24-seven]

I am rebuilding a 2bbl 5,7 Merc from 1997 S/N: K156863.

It looked pretty rough and was siezed due to water intrusion caused by rusted out exhaust mainfolds, had been sitting with saltwater in it for over a month.

The engine is now in parts, allthough i have not pulled the crank and cam yet as I was waiting for a tool to pull the harmonic balancer off. The bores look decent and a will be Ok after some honing.

Now to the question:

The engine has a roller cam, plastic cam gear cover, but not Vortec heads (12 bolts holding the intake). I want to buy a rebuild kit with gaskets, bearings, pistons, Cam, lifters etc but all the kits are either Vortec (With roller cam) on Pre Vortec (with solid lifters). All marine roller cams and lifters that I have found are for Vortec engines, will a Vortec roller cam fit in block or should I just go for solid lifters/Cam and buy new pushrods?

Please give me some suggestions on what to do!

Regards
Martin

 

[Bondo]

Re: Rebuilding a 1997 5,7 - mix of parts Vortec/non Vortec, help please!

I am rebuilding a 2bbl 5,7 Merc from 1997 S/N: K156863.

It looked pretty rough and was siezed due to water intrusion caused by rusted out exhaust mainfolds, had been sitting with saltwater in it for over a month.

The engine is now in parts, allthough i have not pulled the crank and cam yet as I was waiting for a tool to pull the harmonic balancer off. The bores look decent and a will be Ok after some honing.

Now to the question:

The engine has a roller cam, plastic cam gear cover, but not Vortec heads (12 bolts holding the intake). I want to buy a rebuild kit with gaskets, bearings, pistons, Cam, lifters etc but all the kits are either Vortec (With roller cam) on Pre Vortec (with solid lifters). All marine roller cams and lifters that I have found are for Vortec engines, will a Vortec roller cam fit in block or should I just go for solid lifters/Cam and buy new pushrods?

Please give me some suggestions on what to do!

Regards
Martin

View attachment 216378

Ayuh,.... The only thing that makes a motor a Vortec is the Heads,....

Chevy started usin' the roller cam blocks in '87, not '96,..

Yer gonna be needin' alota machine work to rebuild that motor, so talk to yer Machinist 'bout where to get the parts,...
They're generally well connected, 'n have great access to great parts choices,...

 

[Walt T]

Re: Rebuilding a 1997 5,7 - mix of parts Vortec/non Vortec, help please!

You can always buy a wrecking yard Vortec engine and overhaul that, which is what I'd do. The cylinders that had saltwater in them that long may not be salvageable. I guarantee you honing is not going to be enough. Bondo, James Bondo is right the heads are the only thing that makes it a Vortec.
That's my suggestion.

 

[24-seven]

Re: Rebuilding a 1997 5,7 - mix of parts Vortec/non Vortec, help please!

Thanks guys!

Thing is, I live in Sweden and there are really no machine shops that rebuild engines, there is however specialists who build race engines, but they are really expensive... There is also very few 5,7 engine availiable in the scrapyards.

I admit that the state of the engine looks horrible in the picture, but the pistons are now out of the block and the bores is actually in pretty good shape. This is not my first engine rebuild, just the first time rebuilding a 350.

Pretty much every "marine master engine rebuild kit" I?ve seen for the 5,7 is either for a vortec 96- or pre-vortec, up to -96. The Vortec kit always include a roller cam/lifters and pre-Vortec includes solid lifters/cam...

Not shure if the cam is reusable, but will hopefully find out tonight, when I remove cam and crank...

 

[NHGuy]

Re: Rebuilding a 1997 5,7 - mix of parts Vortec/non Vortec, help please!

I'd say look at the Comp Cams Extreme Marine stuff. They have nice cam setups with notes on which springs, retainers, and locks to use. Their web pages have footnotes on which parts require machine work and which don't.
You will want to figure out which heads you have, the numbers are under the valve covers. Once you have the heads identified, look up the chamber volume. With that and some research you can figure your piston types to get the compression you wish.
Your best bet is to check the heads and block, then start researching the parts your motor can use. If you join Comp's forum there are advisors that can punch right through to the answers for you.
I joined recently because I am looking at a cam for a little more power. I tried their CamQuest software which pointed me to the most radical cam I could have used, then when I put in a forum request I got a response that recommended going back one grind to play safe. I am pleased that they said that because I'd rather have my motor last longer than "burn brightly" for a shorter time.
There are other sources too. If you start looking up regular Chevy small block stuff a lot of it crosses over to marine. The main differences are the cam will need a good amount of lobe separation angle. I am looking at 112 degrees. This avoids reversion, a problem in boats that doesn't matter in cars. In a boat if the LSA is too small the overlap between exhaust and intake can allow reversion, pulling cooling water into the combustion chambers at lower engine speeds. This can break your motor because water doesn't compress like air does. Also, boat engines use specific head gasket material, I think it's normally stainless steel, and the core-freeze plugs are brass not steel. I'd look into hypereutectic pistons and gapless rings too. The pistons don't expand as much as standard ones but they aren't as expensive and fussy to run as full-on forged pistons. Gapless rings just hold more compression, which means more power. No gap=no leakage.

Once you have it figured out start web searching the bits individually and in kits for your best deals. Also remember e-bay. And since you are way over there, figure in your shipping costs. It might be best to get everything from one or two places so it goes in fewer boxes.
Good luck, sounds like fun.

 

[NHGuy]

Re: Rebuilding a 1997 5,7 - mix of parts Vortec/non Vortec, help please!

Get that motor dried and oiled!

 

[Bondo]

Re: Rebuilding a 1997 5,7 - mix of parts Vortec/non Vortec, help please!

Thanks guys!

Thing is, I live in Sweden and there are really no machine shops that rebuild engines, there is however specialists who build race engines, but they are really expensive... There is also very few 5,7 engine availiable in the scrapyards.

I admit that the state of the engine looks horrible in the picture, but the pistons are now out of the block and the bores is actually in pretty good shape. This is not my first engine rebuild, just the first time rebuilding a 350.

Pretty much every "marine master engine rebuild kit" I?ve seen for the 5,7 is either for a vortec 96- or pre-vortec, up to -96. The Vortec kit always include a roller cam/lifters and pre-Vortec includes solid lifters/cam...

Not shure if the cam is reusable, but will hopefully find out tonight, when I remove cam and crank...

Ayuh,.... Ya gotta stop thinkin' in terms of "Kits", 'n start thinkin' of buyin' parts that Exactly fit yer application yer buildin',...

That's why I said talk to yer Machinist,...
Bores don't get bored til the pistons are "in-hand", as parts are made to industry manufacturin' standards, but those measurement still vary a tad,...
Yer crankshaft might need turnin', or polishin', if so, main's 'n rod bearin's can be had in smaller increments than in "Kits",...

Get away from the "Kit" mentality, 'n grab a decent cam, like NHGuy is sayin',....

This is also a Great time to consider up-gradin' to Vortec heads, 'n a 4bbl. Carb,....

You can always buy a wrecking yard Vortec engine and overhaul that, which is what I'd do. The cylinders that had saltwater in them that long may not be salvageable. I guarantee you honing is not going to be enough. Bondo, James Bondo is right the heads are the only thing that makes it a Vortec.
That's my suggestion.

Ayuh,.... That's my Cousin Walt,.... Bondo,.. James Bondo,... Licensed to Kill,....

I'm Bondo,.. Bill Bondo,.... Licensed to Thrill,..... :laugh: