1986 260 water pump- sierra or mercruiser?

samm835

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I am buying a new water pump today/tomorrow, but trying to determine if I should buy sierra or stock merc. There is about 45ish price difference, is there a difference?
 

CV16

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I have had bad luck in the past with Sierra impellers. I've had a few where the rubber spins on the hub. Never had that issue with OEM. I had to use Sierra again years later and had the same issue. I will never again buy one of their impellers.
 

samm835

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Sorry I didn't mean to confuse, water pump/circulating pump. Not the foot/impeller pump, sorry for the confusion.
 

alldodge

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I still prefer OEM over aftermarket, even OEM has defects and lowest bidder which can cost us more, but in the long run I'll still take OEM.

Will also say, that the circulation pump is a lot less chancy to use aftermarket then the impeller leg. So in a pinch I would use one. If it started to fail it would not cost me a motor so quickly.
 

samm835

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I'm having some cooling issues, and I'm testing parts and replacing as I go. My boat is an 86, so small things are starting to fail. I'm cleaning out the heat exchanger this weekend, already did the foot impeller. It only over heats once you are going full force.
 

Pete104

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1986 or any year didn't run the water pump in the drive on ANY closed cooling system! They all used the belt driven pump.
 

samm835

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Pete104....I was stating I have already changed the impeller in the outdrive, which it does have....I have grease on tools to prove it. My boat does have a circulating pump ......as per my question which pump is better, I can take pictures along they if needed. This isn't my first boat engine I have worked on.
 

Bt Doctur

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go Sierra and save some money, Marine circ pumps have brass impellers not cast iron.
Must be only a 1/2 system to use a impeller in the outdrive.
manifolds and risers may be getting clogged up a bit. How old are they?
 

samm835

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I'll take a picture tomorrow when at the dock......cause if it has one I have never seen it.....and trust me I've looked. That would be easier to change out vs the circulating pump, as a majority of the times they are off to the side not in front like the circulating pump
 

samm835

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BT Doc, I'm not sure to be honest. Those are my next things to be looking at for issues. What's the correct sierra # for 1986 260 (350) mercruiser?
 

Bt Doctur

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If you have a composite timing cover SIE 18-3599
If you have a steel timing cover SIE 18-3583
 

Pete104

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go Sierra and save some money, Marine circ pumps have brass impellers not cast iron.
Must be only a 1/2 system to use a impeller in the outdrive.
manifolds and risers may be getting clogged up a bit. How old are they?

1986
 
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