One frequent complaint about routine B230F maintenance is that newly-installed water pumps leak. This is either immediately following installation, or over the useful life of the water pump.

Some debate over whether or not the water pump is a 50,000 mile replacement item. Regardless of interval, it is important to remember that the water pump needs proper installation to guard against leaks anytime over the lifespan of the water pump.

Car is a 940 series non-turbo. Today I spent a few minutes reflecting on some of the second-nature things that are part of a 50k service.


1. If the job is being done in conjunction with a timing belt change (very likely if preventative, not repair) then wait until everything is removed to work with the water pump.




2. Tools are important. The one for the water pump, that I rarely do the job without, is a little grinder with a surface cleaning wheel on it. I think it is a 20k RPM tool, and it does a great job of cleaning off the surfaces of the engine block and head, that the water pump touches. Also useful elsewhere in the car for other reasons.

The impact wrench is for the various pulleys. Although not 'recommended', it is SOP when doing a B230 timing belt in a shop.




3. The most important thing to remember when installing a water pump, is to clean the block and head (not visible because of angle) surfaces as carefully as possible, before installing the new pump. This is where the little grinder comes in handy. However, you can easily adapt any other tool to the task, including a razor blade or very fine sandpaper to remove any trace of the old water pump gasket. It is also important not to neglect the underside of the head mating surface, where the mushroom seal at the top of the water pump joins to the head. Often there are traces of old coolant deposits or gaskets left behind, and as a result the new seal starts to leak much more easily, especially in cooler weather.

Interestingly, this car's cam and intermediate shaft seals had been replaced. The crankshaft seal had not. The decision to replace all the front engine seals was made, and the original crankshaft oil seal was removed and replaced with an aftermarket seal of the same brand as the camshaft seals. The original crankshaft seal was not leaking at 96,000 miles.

The timing belt tensioner had been replaced at the 50k service, with a German unit identical to the ones sold by FCP Groton and IPD. No signs of pending failure were present. The unit was replaced, however. Timing belt was replaced with a ContiTech belt. The water pump was the original Volvo water pump, ten years old. The unit was a little noisy, although it did not leak.




4. When installing the new water pump, coat the gasket in grease. You can use RTV sealant, which works very well, but is difficult to work with as it tends to "squeeze" the gasket out from behind the water pump. With grease, the gasket stays put on the block, while the pump can move around to be seated against the head. Coat both front and back sides.

One negative aspect is, the slight film of oil seen in the coolant from any residual grease, can be incorrectly interpreted as oil contamination.

After coating the gasket with grease, hang it on the studs on the block and stick it to the block.




Next, put some grease on the mating surface of the water pump, before placing it on the block. Obviously the pump is without the mushroom seal on top, and the heater bypass pipe O-ring has been placed on the bypass pipe already, which has been cleaned of deposits.

When installing the pump. grease the hole where the heater pipe gasket enters the pump body. This is important to seat the gasket properly. Again, you can use RTV sealant if you like, but it is very slippery and sometimes is hard to work with.

The pump is a new HEPU unit. They are available from FCP Groton, and perhaps others. We source them through wholesale distribution. Definitely the aftermarket pump of choice. I have never seen a failure. I have, to date, seen only one Volvo pump fail, and that was likely because it was original.



Also worth mention is that when the radiator was checked for integrity, it was noticed that the region of the upper hose was showing signs of cracking externally. Although the radiator is not leaking, the usual signs are there. A new radiator was placed on order ($180 vs. $275 wholesale from the dealer) and the problem will be solved shortly.

As a final note, the 900 series cars are a pleasure to do a routine 50k maintenance on. The reason for this is because a standard I-R impact wrench will fit inside the engine compartment without removing the radiator. This is a huge benefit as all of these parts can be removed quickly. This saves a lot of time. On later electric-fan cars, it is necessary to lift up or remove the fan and shroud, but this does not involve having to disconnect anything but the upper screws that hold the fan/shroud in place.
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a Brickboard.com Expat