We have now seen several cases of premature diesel water pump failure. This results in very large bills !
The Saab 9-3 and 9-5 16v and 8v diesels ( Z19DTH and Z19DT) can suffer from water pump failure resulting in severe damage to the engine. The trend we are seeing is that this failure can happen around the 60k and above miles. The Saab schedule interval for the cambelt change is, 72k miles or 8 years for cars up to 2007, and for 2007 models on is 90k or 5 years. We are finding however that the water pumps, which we change at the scheduled cambelt service are failing prior to these intervals. Whilst the cambelts are good for these mileages, the same cannot be said for the water pumps.
We are seeing that the water pumps are seizing, this causes the cambelt to lose its teeth and shred. With the 16 valve engines, if the failure happens at low speeds, idle or startup the usual, ( but not guaranteed ) damage we find is that the cam followers break with no damage to the valves or pistons. However with the 8 valve engines the valves are damaged and in some cases the pistons as well. Obviously to establish the extent of the damage involves quite a lot of stripping down. In both cases this involves you, the owner in a good deal of expense.
An early sign of premature failure is the need to top up your coolant, usually prompted by a ” check coolant ” warning on your display. If this starts, or is occurring. Get the problem investigated, it may be another cause such as a leaking hose, or radiator. Do not ignore it ! Based on our experience. We are now recommending to owners the the cambelt and water pump should be replaced at 60k miles or 4 years ,whichever comes the sooner. If you are buying, or have just bought a vehicle you should make sure that the cambelt and pump have been replaced. Many will say that the cambelt has been done, however we have seen several instances where the belt has been done, but not the water pump. In posting this article we are seeking to inform, not frighten owners. We believe that in doing so we are serving our customers properly. After all prevention is better than cure !
If you wish to talk through this with us please call us on 01892 825208, or contact us through our website at www.motorvationsaab.co.uk .