Why replace the water pump?

[Martyn27_uk]

Up-coming cambelt service ( 1993 car 96K ) - last change in 1999 included water pump swop - what's the real chance of the unit failing and justifying the cost of a "preventative" replacement? I understand the issue about labour costs etc but what are the real odds of a failure?

[kowalski]

My water pump failed last year after the castle combe meet, Temp went through the roof, causing head gasket failure and damaged heads. Cost me aprox 6000 pounds for the engine rebuild, i got a discount from Honda of 1500 but still expensive! Failure occured at 115,000 miles on a 91 plate.

leigh

[Martyn27_uk]

that's what could happen but what are the odds that it might? Would a newly fitted pump have let go after a Castle Combe outing?

[duncan]

If I could predict the future I'd give up the day job!
I've just had my pump replaced at the same time as the belt, 1995 car, 63000m. The pump wasn't replaced at a previous belt change so I felt I was being prudent. On inspection of the old pump it may not, in my case, have been necessary, HOWEVER, any failure is likely to be mechanical, caused by an increased load on the bearings introduced by a newly tensioned fresh belt.
If your pump was replaced last time, it could be overkill, the half way stage is to defer a decision until the belt has been removed and the pump inspected. At least you would have further information to support whatever decision you make.

[kowalski]

The pump that failed on mine had been replaced at the 60,000 service in 1998, but was the old style pump. There is a newer type available which is more reliable but requires a new housing as well. Supposedly there was a problem with the earlier style pumps which Honda know about. Risk of failure could occur due to mileage and age, the failed unit had been in the car 6 years and covered aproximately 55,000 miles. If you have to do the cam belts it is worth doing the pump as well, but up to you if you want to risk it. If you dont have it done at recomended intervals then your warranty might not cover it if it does let go.

leigh

[swlabhot]

How much is the waterpump?

[ctrlaltdelboy]

just to clarify Leigh's comments above, the new style pump does not require a new housing but a new cover, however the existing cover can be used provided you drill a small hole though it to accommodate the drain pipe which is in a slightly different location than on the earlier version.

Leigh is quite right re the increased risk of failure on older style pumps vs the revised version - Honda are not in the habit of making changes just for the sake of it, so if you do not already have the new style water pump fitted, it would be poor judgement not to do it at such an ideal opportunity.

relevant items are here

water pump only - $194 (http://daliracing.com/v666-5/catalog/index_browse_part.cfm?focus=1568)
water pump with new cover - $333 (http://daliracing.com/v666-5/catalog/index_browse_part.cfm?focus=1821)
full 90k service kit inc water pump, cover, plugs, filters, belts, gaskets - $663 (http://daliracing.com/v666-5/catalog/index_browse_part.cfm?focus=986)

[duncan]

Waterpump set, including the lower housing, part no 19200PR7305, £308.47 plus VAT, as at last week.

[710]

I suppose it's a little late, but maybe you can use some of the info on:
http://nsxcb.co.uk/forum/viewtopic.php?t=356&highlight=water+pump
about halfway down there is some waterpump info...