This has been a lively topic on the M100 site for some considerable time. The cost of a replacement pump can be an issue, as well as the method of removal which seems open to debate. I have always maintained that it was unnecessary to remove the pump housing nor the crankshaft damper.
For the first time ever, with the Astral Silver 6.9, I have not been able to remove the pump on its own. It defied all attempts and, in the end, I have had to remove the housing as well which is fitted to the engine block and supports the water pump. It's not one of those jobs that you'd want to carry out everyday as you're always in danger of having to contend with broken, or rounded out Allen bolt heads....and so it turned out - despite all care, one of the bolts broke which caused no end of bother trying to remove it.
There are normally three other problems that one has to cope with. First, if you remove housing and pump as one unit, separating the two on the bench can be almst impossible on account of the sealant that is normally used. Secondly, the housing will invariably be affected by corrosion at the lower two flange heads, and that's how it turned out to be in this instance. That needs to be welded or built up, otherwise the gasket will not be able to provide an effective seal...and thirdly, THAT spacer between A/C bracket and the housing - that's never been easy to fit, and obviously the previous mechanic that had removed the pump must have experienced some difficulty because that spacer was missing. Also, he used an indecent amount of the blue silastic sealant - you only ever require a slight smear.
At the moment, busy fixing up these latest problems. Regards Styria
N.B. My apologies - I hadn't realized that this matter had already been covered previously - more than likely Admin. will merge the two threads. There is not a lot of difference between the two posts, except that I could not remove the pump by itself, and one of the bolts did indeed break off....well, it's the THIRD time.....hmm....well, it's early in the morning !
For the first time ever, with the Astral Silver 6.9, I have not been able to remove the pump on its own. It defied all attempts and, in the end, I have had to remove the housing as well which is fitted to the engine block and supports the water pump. It's not one of those jobs that you'd want to carry out everyday as you're always in danger of having to contend with broken, or rounded out Allen bolt heads....and so it turned out - despite all care, one of the bolts broke which caused no end of bother trying to remove it.
There are normally three other problems that one has to cope with. First, if you remove housing and pump as one unit, separating the two on the bench can be almst impossible on account of the sealant that is normally used. Secondly, the housing will invariably be affected by corrosion at the lower two flange heads, and that's how it turned out to be in this instance. That needs to be welded or built up, otherwise the gasket will not be able to provide an effective seal...and thirdly, THAT spacer between A/C bracket and the housing - that's never been easy to fit, and obviously the previous mechanic that had removed the pump must have experienced some difficulty because that spacer was missing. Also, he used an indecent amount of the blue silastic sealant - you only ever require a slight smear.
At the moment, busy fixing up these latest problems. Regards Styria
N.B. My apologies - I hadn't realized that this matter had already been covered previously - more than likely Admin. will merge the two threads. There is not a lot of difference between the two posts, except that I could not remove the pump by itself, and one of the bolts did indeed break off....well, it's the THIRD time.....hmm....well, it's early in the morning !
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