2qm20 Water Pump

[Mattyb]

Hi guys

My water pump">raw water pump has a lot of water running out from it and it appears to be coming from the hole underneath on the housing. It seems that the hole is meant to be there but obviously not leaking. The question I have is would a rebuild kit do the trick or do I need a whole new water pump? The photo below is the best I can get, I have just taken ownership of this boat so really want to get her cleaned up as you can see she has been a bit neglected

[atoll]

take the pump off,pull the impellor and change both lipseals.........costs about $3 for the new lipseals

[Mattyb]

Thanks Atoll. I wonder how I will go getting it off. That bottom nut looks nice and rusty! Now to find a yanmar dealer!

[tybee22]

Clean it, Osfo it and paint while you have it off also.... on more bite of elephant

[atoll]

Originally Posted by Mattyb

Thanks Atoll. I wonder how I will go getting it off. That bottom nut looks nice and rusty! Now to find a yanmar dealer!

best bet is to wire brush the threads first then apply some heat with a blow torch,then a little wd40 or oil

the lip seals you can find at any SKF bearing parts shop,marine lip seals have stainless springs,though i generally buy the cheaper automotive type and replace the mild steel spring with a rubber "o"ring.

there may also be a roller bearing that will need replacing if it has play,this will need pressing out.

you might also check the sump casing of your engine for corrosion where salt water has been dripping!

[Mattyb]

Actually after doing some goodgling I dont think I have the original pump on it. Mine has a round face on it and the original had a triangular face. Will try put a photo up.

[Mattyb]

Thanks for the other info. I am starting to think a rebuild kit would contain all that stuff and be worthwhile while I am at it?

[Mattyb]

Here is the front of the pump. Any ideas? Definately sounds like lip seals still ( much googling ) love forums like this. Already probably saved me a fortune!

[atoll]

Originally Posted by Mattyb

Thanks for the other info. I am starting to think a rebuild kit would contain all that stuff and be worthwhile while I am at it?

the front cover normally has a jabesco or johnson part number on it if you want to go direct and pay a "marine" price otherwise all the seals and bearings are available from SKF or any bearing supplier at 1/4 of the price

[HopCar]

The hole did exactly what it was supposed to do. When the seal failed it let the water out before it could get to the bearing and into your crankcase.
When you get the pump open check the face plate and cam for wear. Check the bearing as well to be sure the water didn't get to it.

[Mattyb]

Thanks guys. The front plate did look like it had quite a lot of wear on it. We have an skf around the corner so will pop in there thanks atoll. My worry is that th previous owner did little maintenance and I bet this has been running water for a while. There is also a little diesel leak out of a screw on the injector but that's a whole other thread!! Thanks heaps for all the info, I have a lot better understanding of what I am dealing with now!

[charliehows]

better check the shaft too, most likely in a bad way if the seals have been gone for a while, you'll need to check it for pitting where the seals sit.

[charliehows]

oh yeah - its a very original pump, even down to the slotted screws (usually these have been replaced by phillips heads, indicates a pretty low level of maintenance) probably 30 years old. A reco kit is a good idea, but they cost a fair bit, on the other hand if you reco it good and proper you'll get a lot more use out of it. might want to check and see if theres a thermostat in your exhaust manifold - if the condition of the pump is any indication i wouldnt be surprised if the thermostat has rusted away.

[Mattyb]

Rightio then. Am going to take it off tonight and pull it apart and give it all a good once over then go from there. What about just getting a new aftermarket one? How do you know which ones fit?

[charliehows]

Originally Posted by Mattyb

Rightio then. Am going to take it off tonight and pull it apart and give it all a good once over then go from there. What about just getting a new aftermarket one? How do you know which ones fit?

would like to know that meself, i do know that replacing the shaft can be tricky cos there are some issues with shaft length that seem to come up. the kit i used on mine 2-3 years ago had everything but the shaft, housing, cover plate and screws. cost better part of aus$300 but i still think it was well worth it.