RV8 water pump overhaul
Ross Boyd posted a query on the V8BB seeking help with his water pump overhaul. (Dec 09)

Ross Boyd's V8BB posting said I recently had an exchange water pump provided, but found the front pulley is in a different position if you are using a standard 3.9 assembly and your car has air-conditioning. You will need to have the pulley pressed on further to align with the other belts, so it is important to check before reinstalling the new pump.

Stuart Middlemiss responded saying yes the Land/Range Rover water pump is STC483. This is the pump used on the RV8 but it seems that Rover shortened the shaft a little for the RV8. If anyone wants to have a STC483 re-engineered to fit the RV8, the gasket face of pump casing to front face of flange is 87.5mm to 90mm. Measure the old one - discrepancies are probably result of original re-engineering of Land Rover standard pumps. Ensure pulleys are aligned - the alternator pulley can be brought forward by spacing washers if necessary. But of course Clive Wheatley can supply the water pump which will fit out of the box.

Peter Garton in Germany had two questions! What is it that goes or wears in the RV8 water pump and roughly at what mileage? What were or are the symptoms you experienced, Ross?

Max Porter provided an explanation - it is the main shaft bearing that goes on the waterpump. This is due either to overtightening the fanbelt or more commonly on the RV8, to failure of the bearing due to its lubricant (grease) drying out over time. Bearing wear allows slight axial movement of the shaft which lets coolant past the shaft seal through to the bearing which then increases wear.

Symptoms are droplets of coolant dribbling from a small drain hole in the pump body just below the shaft. The droplets are flung out when the engine is running which can be seen as dried water spots on the underside of the bonnet and on the inner wings etc in line with the pump pulley. Wear can also be detected by being able to rock the pulley from side to side by hand. The seal can fail at quite low mileages, mine went at about 8,000 miles. Long periods of little or no use encourage the grease in the bearing to dry out causing early failure. As with all things
mechanical regular use is best and then the pump would probably be OK for quite a high mileage.

As Stuart says, Rover shortened the main shaft of a standard Range Rover pump to aid the fitting of the engine into a smaller vehicle. Replacement pumps are readily available from specialists like Clive Wheatley.

Peter Garton was pleased saying many thanks, Max for your excellent explanation. When I get the Rv8 out of its wraps in the Spring I'll take a look just to be sure.

Ross Boyd also found that if you have the air conditioning compressor installed, you will not be able to lower the radiator as the manual says, unless you remove the compressor first off the four mounting bolts which also means removing the air conditioning lines as well and de-gassing the air conditioning. To avoid this, it is easier to remove the front stabilizer brackets to each side of the front chassis rails and lift the radiator up and out by moving the stabilizer bar out of the way to avoid the bottom radiator hose pipe.

Max Porter responded saying Ross you are quite correct that the air con compressor prevents the radiator from being lowered and removed from beneath the car as it fouls the top hose spigot on the radiator. The bottom hose spigot on the radiator fouls the roll bar and prevents the radiator from being lifted out of the car. It is of course, much easier to unclamp the roll bar and move it out of the way rather than dismantle the air conditioning system. Rover's workshop manual does not mention this so you discover this point as the job proceeds.

Just another couple of points. On checking the pump for wear by trying to rock the water pump pulley. Wear is easier to detect if the fan belt is slackened off a bit first. The other point that should be mentioned is that the water pump is the same unit for RV8's both with and without air conditioning. Initially I went to my local Land Rover main dealer for a pump as the price was considerably cheaper. There was the new pump on the main dealer's counter and it looked identical in every way to the one removed from my RV8. I was really pleased at the prospect of saving quite a bit of dosh but sadly on closer inspection of the two units side by side, it was noticed that the main shaft was shorter on the RV8 unit. Definitely a case of "sod and his law" once again.
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