World of Reliant,

I bought a new water pump for my 1986 Fox. Unfortunately the casting is slightly different and the bracket for the alternator doesn't fit. Wrong pump or have they changed? General problem or one off? Suggestions for a remedy please. The car is taking up space at a garage and they are not happy!

i dont understand that, ive known casting been bad on some pumps which stop them going all the way on the studs so you have to drill the holes out slightly but ive never known one stop one fitting the alternator bracket as it just fits on the stud the pump slides on!

I've now see old & new together. It appears that a small amount of the casting has to be ground away around the bolt hole which also holds the alternator bracket. Looking closely at the old pump, it seems that this is what was done to it. The garage were reluctant to alter the new pump in case they went too deep and broke into the water channel. Unless I hear differently by tonight, the garage get out the files tomorrow. I wonder if every water pump has needed this done since the 1980s?
The new casting looks a lot rougher than the old one.

I replaced a water pump last year and the alternator bracket fitted fine. The pump was one with the pressed in steel tubes for the heater hoses, rather than the cast ones.

I discovered that there are 2 different alternator tension bars, a virtually flat one, used on early engines and one that has a pronounced double bend/offset to step the water pump fixing end out a tad, fitted from mid-term Rialtos and Foxes onwards I was told, probably about the time the three-bolt plastic fans came in. The flatter ones don't fit later water pumps, unless a washer or two is put between the bar and the pump to space it away from the pump casting, if the stud is long enough, or the casting is filed away a little.

Difficult to describe in words, if I've got a pair out in the shed I'll take a photo. I found out about the problem when I first changed the water pump on the Jaffa, sometime in the late 80's. I just fitted the later bar and also adjusted (added a couple of extra washers to) the lower alternator front spacer (the back one is a sliding system) to bring the alternator forward to meet the new tension bar, then pushed the alternator pulley a little further on to keep the pulley in line with the other two - a bit of a faff but still fine today 2 decades or more and at least a couple of further alternator replacements later! Back then, replacement alternators never ever came with a pulley fitted, you had to change this over from your old one..... Even if only slightly out of alignment, the pulleys will soon cause the fan belt to fail and the belt will also become noisy.

A point to note with new water pumps is to look carefully at the construction. If the hose stubs are part of the actual casting the pump will definitely not last long. A flood of these has come on the market and they are pants!!!! Any pump with separate, not cast in, hose stubs (screwed or pressed in) should be fine, though these pumps do tend to cost a bit more.

John

a good point that Tony Mentioned...........if your pub has the water tubes made of cast its the cheap quality pump, if they are steel inserts its the good quality one

When I offered up my new water pump for the Rialto it was out of line by the thickness of the pumps pulley wheel flange. The vender twice offered to return my money but as the measurement of 45mm from the pulley face to the block was correct there wasn't any point.
The wall thickness of the pulley is much thicker and will have to be pressed on further by about 1/8 inch or more which is something I am just about to try after making up some dolly's on the lathe.
I only hope the wheel is held on with a press fit and not Locktite as it might come loose if the wheel can be moved. Anybody else had this problem ?
This pump has the two 1/2 pipes glued in.