Difference in marine engines?

Engine, ignition, fuel, cooling, exhaust

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JMcTurnan

Difference in marine engines?

Post by JMcTurnan »

So I have an OMC 235Hp 351w engine in my truck. I pulled the dizzy out yesterday and some teeth were slightly sheared again, and a whole cam tooth was grinded down. I have an automotive dizzy in there, does anyone know if theres a difference in the gears? I finally got it back in time, and it's running strong. But I don't want to let it go too long before I ruin my whole cam.
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Re: Difference in marine engines?

Post by DuckRyder »

If a "whole cam tooth is grinded down" the cam is already ruined, any new gear you put on it is going to wear prematurely.
Robert
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Re: Difference in marine engines?

Post by Redcap »

DuckRyder wrote:If a "whole cam tooth is grinded down" the cam is already ruined, any new gear you put on it is going to wear prematurely.
Yup, that cam is toast.

And it is "distributor".
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Re: Difference in marine engines?

Post by DuckRyder »

In addition, to answer your question, it depends but some common differences are:

Heads may not be drilled for automotive emissions.
It might have GT40 heads. (Real ones not "P" heads)
Water jackets may have bronze inserts, particularly in aluminum parts.
The cam will be specific (it is [or at least was] geared for good performance)
It might be reverse rotation, so the cam and crank would both be specific (if you have it running that probably is not the case)

Pleasure Craft Marine (PCM/SeaMaxx/Crusader) were the last to use Fords, they negotiated a contract to ensure their exclusive use when Ford began to phase out the small block. The final iterations were rated at about 310 hp @ 44-4800 rpm, this was a fuel injected "GT40", the same engine with a 4bbl was rated at 290 hp (I am not sure of the RPM). They also made a "base" engine that I believe was ~245 hp and may be similar to what you have. I do not believe the base engine had GT40 heads.

I am unfamiliar with OMC's use of Fords, but by the time I bought my Nautique in 1998 PMC was the only Ford user and had been for a while.
Robert
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"An unarmed man can only flee from evil, and evil is not overcome by fleeing from it." -- Jeff Cooper
JMcTurnan

Re: Difference in marine engines?

Post by JMcTurnan »

Well I don't know if it's completely grinded down, I will have to take a look at it. It's running fine as of now after getting it timed. But I know it's a matter of time. I got a book on the whole boat, with detailed engine specs and directions so I'm sure I can find out. It's not reverse roation, not water jackets. By emissions what do you mean? The cam is a performance cam I know that. Its a clean engine, do you think I could get away with putting a new cam without changing bearings? I don't know how to chance cam bearings and I know most shops make it mandatory to cook it out.
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Re: Difference in marine engines?

Post by JMcTurnan »

The engine ran good before my crank gave out with the dizzy and was never grinded. So I am not sure. I know I could just put the same cam back in and drop the equivelent of its original distributor. But then Id have to get rid of electronic ignition.
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Re: Difference in marine engines?

Post by 1971ford »

Come on man, do you try to make your posts confusing lol
-Ryan
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Re: Difference in marine engines?

Post by Redcap »

Uh...do you have any idea on what you are actually talking about? No one else does, that's for sure. :? :? :?
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Re: Difference in marine engines?

Post by DuckRyder »

I know that I've said this to you before and I'm letting the two previous replies remain in hopes that they will help you to realize that people are reading and are frustrated with the level of information provided.

I must assume that if you've posted here, you have a problem or question that you would like an answer to, in order to get that answer you are simply going to have to put some time into presenting the question in a logical and organized manner.

About all that I can tell you from the information provided is this:
  • If there is any area of the cam which fits any reasonable man's definition of "grinded down" at all, the cam is scrap.
    You can change a cam without changing bearings in most cases.
    If you continue to run the engine with things like cam gears wearing it is going to destroy the engine.
    By emissions I mean AIR injection, EGR, carburetor heat and the like.
    I'll assure you it has water jackets.
Robert
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"An unarmed man can only flee from evil, and evil is not overcome by fleeing from it." -- Jeff Cooper
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Re: Difference in marine engines?

Post by 70_F100 »

THANK YOU, DUCKRYDER!!!

That has been needing to be said VERY badly!!!!!!!!!
Wise men talk because they have something to say; fools talk because they have to say something.--Plato
Why is it that there's seldom time to fix it right the first time, but there's always time to fix it right the second time???

That's not an oil leak :nono: That's SWEAT from all that HORSEPOWER!! :thup:
JMcTurnan

Re: Difference in marine engines?

Post by JMcTurnan »

It's cool, sorry. Just been very busy lately. Its not fully grinded down, but it will get replaced anyways. It does have egr, not quite sure about air injection, it has a street carb. I took off the marine, not sure about carbretor heat. I havent been driving it, Im letting it set till I can save up some money to fix it. I don't know that much about engines, but I have people that help me get along. Put in a crank kit by myself which is probably the most internal I've done. I have never done a cam shaft or any of that. But ill get someone that knows what theyre doing to help me.
JMcTurnan

Re: Difference in marine engines?

Post by JMcTurnan »

Yea sorry bout the confusing posts, just been in a rush lately. My dad has had 4 surgeries in past week, and I'm in and out. It's really rough right now.
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