Pump Leaks Water and Oil


Most likely due to freezing. When I run the pump, it cannot sustain pressure with an open nozzle for more than an instant. Water drips out from 2 of the 3 “cylinders,” where the brass head meets the ceramic body. The water that leaks out has a light oil residue on the top, minute enough that you can only tell by observing the “rainbow” effect upon changing viewing angle.

The oil reservoir has no water in it. However, the area around the two pistons has the light frothy “chocolate milk of death.”

So, is this a case of water seals going bad, causing water to drip into the area where only oil should be? Or, is it a case of an oil seal failing and causing oil to mix with water?

The fact that it is losing pressure and producing a small burst on an interval makes me think it is just the water seals in the head that are bad. What do you guys think?

More than likely. Mine just did that today too. Find your pumps pdf diagram, it’ll have the part# of the kit. Or you could call ar north America for just the seals part#.

did you remove the brass manifold ?check your plungers for cracks. and the seals I had one that was doing the same. had a cracked plunger.

I did, but I didn’t see any. Where were the cracks in your plungers?

I did remove the brass manifold.

my plunger was actually cracked in half. it was visible to see. also the little spring and washer and nut had come lose on the plunger. it is a simple fix for you just have to do a little more trouble shooting…the seals could be dried out and or warp .may have to replace them.

Gotcha. Definitely no damage quite so obvious. This would be easier if I knew exactly how these mechanisms worked. I see around the plungers there are some seals that look like they are there to keep oil in. Then the plunger goes into the brass manifold which is where it looks like the water flows through.

So, if oil is SUPPOSED to be in the area closer to the pump crankshaft, it looks like it is just the water seals that are leaking.

ok .it may just be your seals.i had the same problems with a cat pump. I purchased the new seals and plunger no problems since, been a year and running good…you seem to be mechanically inclined keep at it you will get it worked out.

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Thanks! I only have ~$500 in work scheduled for pressure washing remaining this year. Deciding whther to spend $50 on seals to attempt to repair, $250 on another pump, or just tell all those clients I will schedule them in the spring and use the money on my Fall start-up.

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