Leaking dash heat circulation pump

[gmcbuffalo]

Call these people

P M Pump CO Pm Pump Company 5032 Stanley Farm Road Salem, VA 24153-7948 map

[Denny]

Will send additional photos tomorrow. I cannot separate the brass pump section from the motor part because the impeller is holding it together. I have tried prying between the brass pump and the motor but nothing moves. I believe once the impeller is released it will all separate so I can replace the seals. It seems to be pressed on instead of a nut holding it on the shaft.The Black Bull Dog is simple compared to the bus.

I will contact the pump company on Tuesday. Thanks for the help.

[Gil_J]

It looks the same as what CC installed for the Webasto. If so, get a bigger hammer. The impeller is just stuck. Once you have the motor off you can press or beat it off.

[Pete]

I would think that there should be an allen stock screw holding the impeller onto a slotted shaft. Check closely, it may be covered by sediment/rust.
Good luck in getting it off!

[Gil_J]

Here's what mine looks like off the motor. If the same there's set screw. BTW, I bought a replacement for about $400 and when I get around to putting this one back together it will be my spare.

IMG_20130527_112046_542.jpg

[Denny]

Gil,
My pump is not the same. It is not a converter added pump but one from Prevost. I believe we all have them in the front bay behind the bumper. You have to crawl in the bay and look on the ceiling to find it. It aids in circulating the "water" from the engine compartment to the front of the bus. I checked online on the Prevost site, under Maintenance Manual, and it requires a puller that is available from MP Pumps, the manufacturer of the pump. There are no set screws on impeller.

I have a MP dealer about an hour from me so tomorrow morning I'm going to call them and see if I can get a new one and rebuild this one to keep as a spare. MP Pumps has a list price of $522 on their website so I'm hoping to get it for less using my company. MP is in Michigan but this dealer is only an hour away so I hope I'm taking a trip to get it in the next couple of days.

Thanks for all of the replies and help. I will let you know the results when the pump is on. Again, thanks to all.

[Gil_J]

I meant to say there is not a set screw. I think the converter and Prevost pumps only differ in their water fittings and voltage. I too should have used a puller, but was able to use a mallet without damaging the shaft. Even the converter one that is commonly used in school buses is expensive.

I'm curious, how much coolant came out when you removed the pump?

[Denny]

I shut the valves off in the engine compartment and collected about 5 to 6 gallons of coolant. Fortunately there is enough room to get a five gallon bucket in the compartment. I hit the pump many times with a brass hammer and it would not move.