I had water pump problems in October 2010 when the bearing failed on the water pump. No problem to sort but I didn’t have time to fix it so purchased a replacement pump from an well known Jeep parts provider. I never saw the original old pump as a friend of mine installed it for me whilst I was working. (He owed me many favours) The replacement pump was made by US motor works and was part number US8909 and listed the VM diesel Cherokee as one of its applications.
Anyhow, all appeared to be well and I don’t tend to use the jeep much above 60 mph very often, that and lots of cold weather I think hid a developing problem with regard to the water pump.
There is another post on here where I was getting overheating issues and loss of coolant that turned out to the heater core. This I replaced (there is a post on here with some pics someplace) with a new one and all was pretty much ok. However I started to use the jeep more at speed and found that over 70mph she would nudge up to a shade over 100 degrees. So I flushed the radiator and cooling system etc. But nothing much improved but the problem wasn't that bad it needed tearing to bits to find.
Fast forward to last week and I started to get an intermittent squeak out of the engine bay. So off came the belt and I spun everything to see if there was a pulley problem. Low and behold the damn water pump had play in it. Off it came and I headed off to ECP in Leicester who had one in stock for £37. Result.
The USMW pump differed from the ECP pump in that the ECP pump, made by Circoli (ECP part number 201510091), didn’t have the cone end. Both pumps had 76mm diameter impellers.
I have to say that since fitting this, the odd cooling problem has gone completely and it is running perfectly and she hardly moves up the gauge even though I screamed her down the M42 at an experimental speed
. I can only presume that the USMW pump may have been supplied in error, right box wrong part sort of thing, and that the cone shape that extended into the back of the water pump housing was impeding coolant flow hence the increase in temperature at higher revs but otherwise all being fine.
Does anyone know which shape is supposed to be in there, just to get a definitive view?
Oh, and the lumps and bumps on the old pump are part of the casting. Not some sort of rusting / debris buildup.
