340 marine motor?? differances?

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snowmobiler7c

snowmobiler7c

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I have been planning on rebuilding my 318 for my 70 swinger because it seems like I cant find a fair priced 340 complete locally unless the price is high. I just ran across a guy selling a 1967 boat with a complete 340. Not sure if it runs but has odviously been apart before becaause its painted red. BUt anyways can these motors be put in a vehicle without too much trouble? bell housing bolt up for an auto trans? still have x heads?

I once heard circle track guys loved maarine motors because they turned counterclockwise, but I beleive that would only be from a boat with twin.

Seems like they must have been common boat motors. THis is the 3rd ive found locally, but the other two guys wont sell. thanks for any info.
 
Some marine engines run "backwards" some single, some twins. Old ski boats usually ran backwards. Only the crank and cam are different and the crank is only different on the rear seal knurling. If it was a raw salt water engine I'd pass. Can you find out what boat it was in? Look it over good. not sure what heads it will have. Trans bellhousing bolt pattern should be the same.
 
I recall someone telling me that some v8s used in boats run backwards. I don't know if that was someone pulling my leg or not though. Don't even remember where I heard it.

Edit: nevermind. Apparently it is true and I was beat to the punch. haha
 
Yes some v8s in boats run backwards, the reason being for putting one engine port, and the other starboard, but later it was found out that they could be spun the same and the marine transmission or Velvet drive would run one opposite. If the boat has one engine, it likely spins normal, as when ordered - it is easier to build a lot of marine engines that work the same as a car engine, and then half as many for the ones that spun opposite. My dad has spent a lot of time with marine chrysler and ford engines, and says that sometimes the marine engines will have larger valves, different cams, a different carb, and the obvious marine manifolds. Otherwise on older engines the marine application made more power than a car application on the same engine.

But as stated above if it saw salt water time and had a raw water pump - forget about it.
 
1968 340s were red. But anyone with a can of red spray paint can make that happen.

The dead give-aways for a marine engine are water cooled exhaust manifolds, and a carburetor that vents back into itself.

I've never seen a reverse rotation 340, but I have seen a reverse rotating 318. It was part of a twin engine boat. Other than being a marine engine, it did not look unusual. There was nothing but the tag on the engine to say that it was counter rotating.
 
Low compression, 318 heads. They can be reverse, fairly sure they can be standard too- most single engine boats were reverse rotation. So the answer's X heads are very unlikely, probably has 318 motor home heads.
 
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