I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Chevyboy454

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Bought another boat and it's got a 2.5l inboard. I've always owned outboards so this is relatively new to me. Sure looks like the engine in my old S-10. Can I just get a 2.5l from an S-10 and swap it out??

Thanks Rick.
 

TilliamWe

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Nope, they aren't even close to being the same engine. For one, your boat engine has the intake and exhaust ports all on one side of the head. Your S-10 did not.
 

Chevyboy454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

I understand the head is different, I suppose I should have worded it better. I mean usage of just the block and transfer all the other stuff over?

Cheers Rick.
 

RogersJetboat454

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Dave1251

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

No, the marine engine is not based on a auto/truck engine. The marine engine is based on an industrial engine.
 

Fordiesel69

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

No, but the 2.5L 120HP is literally a dime a dozen. Just get a rotted boat and pull the motor.
 

Chevyboy454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Bummer, found a 2.5l in perfect running order in an S10 for 100 bucks, guess I won't be buying that one. Rotted boat is an option I'll have to look at, down side is what to do with the hull afterword..

Thanks Folks!
Cheers Rick.
 

kd7isf

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Are you sure it's blown?

What are the symptoms -- could just be a gasket or something -- these engines usually rot out before they wear out or blow out -- :)

Sorry, you can't use an S-10 block -- it's totally different technology..
The boat 2.5 is the "stovepipe" design whereas the truck version is the "iron duke" design..
The head deck on the boat engine will not match up to the block deck on the truck engine..
The push rods are in slightly different locations and move at a different angle..
The cam is an automotive cam and the marine cam from your boat block won't fit..


Now that said, if you can find an old '60's chevy II nova with a 2.5 (or 3.0) 4 cylinder, THAT engine would work -- just swap your marine cam in (I'd recommend using the lifters from your marine block as well since they are worn in to your marine cam -- keep them in the same positions), install brass freeze plugs, and swap your oil pickup tube and oil pan onto it.. DO NOT use automotive alternator, starter, fuel pump, or carburetor....

Hope this helps...
 

Chevyboy454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Don't know what the symptoms are as I finally picked it up last night. Guy doesn't have a clue whats wrong with it other then his tech said it was blown. I'm going to see whats up tonight with it. Bugger part is I was given one of those old 2.5's long ago and turfed it, went with a 350 in my Nova. I'll keep you posted.

Cheers Rick.
 

Chevyboy454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Update: Well the engine is whopped. She is seized up. I can get her to tun a little with a bar in each direction but it locks up. Feels kind of like a thrown rod or something along those lines. As for a free boat with an inboard that works (I've been on the used sites all summer lookin for a bigger boat) There is nothing around here. Even if it has any sort of part on it that looks useable people expect to get paid. Oh well Guess I'm in the market for a good used 2.5 or 3.0. Anyone got a spare one kicking around for relatively cheap lol. On the bright side there is 3/4 of a tank o gas in it!

Cheers Rick.
 

Bt Doctur

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

You do have the outdrive removed because the drive can be siezed not the motor
 

Chevyboy454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

I plan on pulling it tomorrow to have a look. Just talked to the guy and he said there was a crack in the block that was repaired and his tech says must have leaked internal, hydro locked and bent a rod or something. Funny as the oil looks relatively clean with no debris. I'll know more tom.

Cheers Rick.
 

Chevyboy454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Thanks BT Doc!! You were correct. Engine is a runner, the repair to the cracked water jacket is leaking a bit but it does run. Seems a little hard to start but I suspect carb is gummed up. With the water on and plugs out I do not see any water in the cylinders, nor is there and evidence on the plugs of it not burning properly. Oil is clean and not milky so I suspect the engine will do me for a while. Now to find an electo shift OMC stringer drive. I am not fond of the electro shift setup but beggars cant be choosy!

Cheers and thanks again! Rick.
 

RogersJetboat454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

This thread is posted as;
I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Yet....
Now to find an electo shift OMC stringer drive. I am not fond of the electro shift setup but beggars cant be choosy!

Somethings not adding up here!?
Did the previous owner not know what he had?
 

Fordiesel69

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Just a guess, but maybe he reworded his post here to get more results. I posted my OMC problems on the OMC section and it takes 2-3 days to get a reply unlike 1-3 hours here........
 

Chevyboy454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

I'm going to assume he did not know the engine still ran. The way he explained it he has had nothing but grief from this boat this year and just wanted to be done with it. Too bad the crack in the block is still leaking. I'll have to pull the manifold and see what can be done there to stop the leak. Don't even know if I want to keep it yet, guess that all depends on how much the foot is going to cost me.

Cheers Rick.
 

Chevyboy454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

Just a guess, but maybe he reworded his post here to get more results. I posted my OMC problems on the OMC section and it takes 2-3 days to get a reply unlike 1-3 hours here........

No I didn't reword the post, I was told by the original owner before I bought it it would need an engine, so before I even had a chance to look at it I asked if an S-10 engine would work. His "Marine tech" was wrong, turns out the outdrive was seized. I hadnt looked at it and assumed it was a Merc, didn't know it was OMC until I actually got it.

Cheers Rick.
 

Chevyboy454

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

I can assume this is not a good one? As I said before I/O is all new to me, I know the old Johnny/rude setup was a pain in the outboards so I am assuming the inboards are just as bad?

Cheers Rick.
 

Fishermark

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Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???

About as bad as it gets.

Regardless of how good or bad they were when new - the real bad part now is finding a competent mechanic who can or will work on one for you. They haven't been used in decades - and the company is out of business. Plus the transom cutout is completely different so you cannot easily change to another type.

Other than that... no problem! ;)
 
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