WANT TO BUY 1959 Gas Thermodyne Oil Pump for B85

[loyaldavis]

The oil pump on my 1959 mack fire engine is only putting out about 8psi. I had it "rebuilt" but I think they only shaved the head to increase pressure, which went up to 10 psi. The gears look badly worn and I can't find any rebuild kits for the pump. I would appreciate any suggestions, or, if anyone has a working oil pump they want to sell, that would be great.

[BOB DINGSDALE]

I take it it's for a 707 gas in a fire truck?Will any other OHV mack engine ones work?

[theakerstwo]

If its a 707 engine i am sure the pump from a end 672 673 707 will be same.I have been in those engine but been 45 years and still remenber that it look same as a diesel inside.

[loyaldavis]

Thanks, I don't know the answer to what gas engine I have, I will do a little more research and get back to you. I really appreciate your posting.

[loyaldavis]

The engine is a 707. I have found complete engines for sale, a few sites have a dozen or so parts for sale, but no oil pumps. Does anyone know of a source for an oil pump, whether it's from the gas engine or one of the compatible diesels? If I don't find an oil pump or am not able to rebuild this one, is the only alternative to r&r the engine?

[Firemack]

Check with Matt Pfahl

Here might have one, his ad runs on the banner screen

Firemack

[loyaldavis]

I have some new information. We contacted the company that did the rebuild on the oil pump and he said he bench tested the pump at 45psi before he sent it out. Assuming that the pump didn't immediately fail and the bench test was correct, it would seem we have a pressure leak in the engine. There was no metal in the original oil to indicate a problem with the bearings. The piston rods were tight as well. The oil runs thru the oil filter separate from running through the engine. I am wondering how the oil filter assembly creates back pressure. Is there some kind of valve in the oil filter assembly that we should check? Or and other ideas?

[Gmerrill0516]

The filter should be a bypass type and should not in my opinion be the issue. I'd guess you have a bearing problem or some other issue. Is there a spring/presure relief in the pump? Maybe the spring failed and is not allowing the pump to build pressure. I have a 707C that I will either part or sell shortly and I know the pump works...I have to get my stuff running first which will be in a month or two (good Lord willing). I'll post what I have on the parts section or I can let you know if you like.

Good luck.