4.3 Mercruiser mechanical fuel pump: Marine vs Automotive

Prophammer

Prophammer

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My 1987 Mercruiser, 4.3, mechanical fuel pump isn't working so I removed it and dissassembled it and found it corroded and rusty inside. I checked Napa for a Mercruiser fuel pump, the guy told me he can get it Marine style but cheaper Automotive style. He then went on to say; he bets 'they are the same internally' , 'they have the same # stamped on the case'. Is it sheer folly to consider using the automotive version pump to save 70 - 80 dollars? And can I do the same with the power steering pump?(it leaks fluid)
 
L

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Re: 4.3 Mercruiser mechanical fuel pump: Marine vs Automotive

If its not USCG Approved you do not want to chance it.
 
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Jasen

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Re: 4.3 Mercruiser mechanical fuel pump: Marine vs Automotive

They are mechanically the same. The difference is the automotive pump has an open weep hole that will leak fuel out of it when the internal diaphragm fails filling your bilge with fuel. Marine units have a tube that directs any fuel leakage to the intake stream where it is safely burned in the engine.
My friend almost lost his life that way when his boat exploded because of his automotive style fuel pump leaked in his bilge and got ignited by a leaky plug wire.
 
Prophammer

Prophammer

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Re: 4.3 Mercruiser mechanical fuel pump: Marine vs Automotive

Thanks for the replies! I did notice the approx 1/8 plastic line from the weep hole to the carb. Is that the only thing that makes it a Marine fuel pump, or does it have to meet corrosion resistance specs or some other specs too?
 
Bondo

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Re: 4.3 Mercruiser mechanical fuel pump: Marine vs Automotive

Parlay said:
Thanks for the replies! I did notice the approx 1/8 plastic line from the weep hole to the carb. Is that the only thing that makes it a Marine fuel pump, or does it have to meet corrosion resistance specs or some other specs too?
Click to expand...

Ayuh,... That's Enough reason all by itself...

That keeps ya fro Blowin' up yer boat....

Put a Marine pump on it....
 
Prophammer

Prophammer

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Re: 4.3 Mercruiser mechanical fuel pump: Marine vs Automotive

Ok, Ok, I'll put a "Marine" pump on it. Thanks, I just have to use my other boat untill I get this one fixed, shucks!
 
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