4.3 merc water pump problems

[z284u2try]

4.3 mercruiser 1998 18.5 bayliner alpha 1

Looks like the seals on the engine water pump maybe on there way out. I saw a drop of water from the weep hole the other day on the hose.

My question is about a replacement pump anyone have a part number that I may get at my local auto part store?

Any difference in a auto water pump versus a boat?

I am also going to change the thermostat but would need a part number I think it may be around a 180 stat but not so sure.

I guess the best thing to do would be to take the stat and pump to the auto part store.

 

[Maclin]

Re: 4.3 merc water pump problems

I would not recommend an auto parts store. Some may be able to x-ref to the Marine versions (like NAPA I have heard), but the automotive pump and t-stat will not be good for your engine.

The automotive stuff is designed to work in nice clean corrosion-protected fluids and will corrode and fail much quicker when used in the Marine environment. Plus the fact that auto t-stats are a much higher range. In the auto world 180 is low whereas in the Marine world with raw water cooling that is high and 140 or 160 are the norms.

The engine cooling circulation pump is built with different materials as well for the impeller and other seals, etc.

Go with OEM from a Marine dealer/site, that is my recommendation.

 

[matt2807]

Re: 4.3 merc water pump problems

I did this job 2 weeks ago, same engine.

Pump was about $140 from the dealer, gaskets included, took a couple of hours.

Take your engine s/n to the dealer, they will give you the right one.

 

[z284u2try]

Re: 4.3 merc water pump problems

Thanks for the comments guys. 140 is very steep for a standard water pump. I pulled the pump yesterday after work and going to napa today.

 

[searay3]

Re: 4.3 merc water pump problems

Running in salt or brackish water, a genuine marine pump is a must. In freshwater though, a chevy $30 pump of the appropriate vintage will last for years, just like the manifolds. With the cost savings could replace again and again before reaching the $130 mark. Only in sweetwater though.....

 

[JustJason]

Re: 4.3 merc water pump problems

140 is very steep for a standard water pump

There's nothing standard about the pump... so i don't understand why you assume that. Same houseing, yes, same guts, no. Different Impeller, beefed up bearing and seals designed for constand high rpm operation.
$140ish sounds a little high, with some searching you can probably get one for a little over $110.

 

[Don S]

Re: 4.3 merc water pump problems

There's nothing standard about the pump... so i don't understand why you assume that. Same houseing, yes, same guts, no. Different Impeller, beefed up bearing and seals designed for constand high rpm operation.
$140ish sounds a little high, with some searching you can probably get one for a little over $110.

He will be finding that out in short order as he installs his second pump.