496 water circulating pump
 

I noticed today that I had some dried-up rusty colored residue sprayed over the front of my 496. Also some on the bilge floor. It looks to have squirted out of a weep hole on the front of the block water pump. Has anyone ever seen this? Why would it be rusty? The engine coolant is only two years old and looks fine. I'm concerned my memorial weekend will be having to change a pump. Woo Hoo.

Check that your not dripping water from above and the water pump pulley is splashing it over the motor

so did your AF level go down in the reservoir ?

And how did you mix the AF and water ? Hopefully you used DISTILLED Water for a 50 / 50 mix of Dex Cool and distilled water.

I do have plenty new circ pumps for these 496's with the proper gaskets as well. They are made here in the USA.

Thanks for reply. It definitely came out of the pump hole. The fluid level looks normal in the reservoir so I didn't loose much. I did not use distilled water to do the mix although my well water here is very soft. I have to add a large amount of calcium to it for my hot tub.

I'm going to go ahead and change the pump and I can easily change the coolant at the same time if you think the water may be an issue. I'm going to loose a lot anyway. It will also be a good opportunity to clean the heat exchanger and change the thermostat. My engine temp varies over a wider range than it used to (+/- 20 degrees) when running.

How do I order one of your pumps?

temps swings can be a sign of a bad circ pump I have reported that issue in the past on OSO. When we





had a bad run of these circ pumps https://cimg1.ibsrv.net/gimg/www.off...b26022d745.jpg
in the pic - the temps swings happened all the time. We seen this from many not just one. Prob not the case whats happened to yours but I would not rule it out either.

How fast are you needing a pump ? And I would install a New T stat as well. Have those to.

I plan to start disassembly this comming weekend, mostly just to see what all I'll need. I'm going to use this as an opportunity to clean up a lot of stuff. I would need a new pump to put back on by the following weekend.

Just noticed my port engine circulation pump with a little puddle from the weep hole as well. probably going to replace both just so I don't have to worry about the other going bad on me this year.

If it is coming out your weep hole the pump is going bad. I would replace before getting after it.

Also your spark plugs wires shipping out to you this week. THANK YOU. I was at the marinas last week working on boats as to why I could not ship.

Finally received all the parts to do this job and ready to install the pump. The Merc shop manual says to apply Perfect Seal to the 4 attaching bolt threads. Why would I want to apply gasket sealer to the threads of bolts going into the block?. Anti-seize maybe but gasket sealer? Is it a misprint and they mean the gasket surfaces? They don't mention putting any on the two gaskets.

Back on the water and running good with no leaks. Engine temps are steady at 160 when running now. Lots of stuff to change with that job.

At least 5 tubes on the heat exchanger were blocked by small pebbles. I had to dislodge them with a .17 caliber rifle cleaning rod (.22 is too fat). I would never have seen them without removing the exchanger, both end caps and looking down each tube. Crossover to water pump seal was also damaged and the retainer screws were seized. That was fun.

Just saw this; when you reassembled...
I assume you replaced both of the heat exchanger end cap gaskets, as well as the grommets from the h/e to the crossover, right?
Both can cause problems as they age.

Good to hear. Yep it's amazing what gets into the HE tubes. Compressed air also cleans them out really nicely. While winterizing I pull the endcaps, blow out HE, backflush seawater side cooling system. Those retainer screws are always seized it seems. Dissimilar metals/antiseize is your friend.

Yep, all new gaskets, O-rings, seals, grommets, pulleys, T-stat, belt and 19 quarts of fresh coolant. Also plenty of anti-sieze, Permatex, rust remover, paint and corrosion guard.

Those screws were really soft stainless so I pounded torx bits into them and used an impact wrench. Crappy little things.