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BN2 water leak

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mbrooks

mbrooks

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After a long fast run to the Ligurian coast (Italian Mediterranean) and back to Milan the other weekend, yesterday I spent some time on the 100 and noticed a water leak from the front of the engine, only when the engine is running. It seems intermittent in that sometimes when I start the engine it leaks, sometimes it doesn't. I am suspecting a failed water pump seal/bearing, but before I spend money on a new one, I wonder if other people have had any other leak causes? Another question - if I do need to replace the pump - I notice that the Moss catalogue says their pump does not allow the heater tap valve to be fitted. Since I am in Europe, my intent would be to buy from one of the UK suppliers. Any recommendation for who to go to to ensure I get the correct pump with the heater tap valve connection? Any words of wisdom on fitting a new pump?

Mike Brooks
'56 BN2
 
Any chance of having the water pump rebuilt? I guess it is obvious that you also checked the radiator,hoses and gaskets. A small leak might only show up under pressure (engine running).

Bruce
 
Mike--

It's a failed seal for sure--it will only get worse. Here in the states Bill Bolton sells rebuilt pumps on an exchange core basis and supposedly uses a better quality material for the seal than originally furnished. I'd bet that any of the UK suppliers (CAPE, DW, Healey Spares, etc.) carries either rebuilts or new ones.
 
Bruce,

The hoses are all OK. It is possible it is the pump-to-block gasket. I think the installed pump is already an after-market pump which is not re-buildable (no grease point). However, if you know of a rebuilder please let me know.

Mike
 
Thanks Michael,

Do you have any info on the heater valve tapping? I would hate to do an exchange and end up with ab incorrect pump body.

Mike
 
Mike--

I believe the pumps are rebuildable whether or not there is a grease point. The leak comes out the little window in the bottom--nature's way of letting you know that you have a problem.
 
Hi Mike,
Michael O is correct. The very old pumps required greasing. Rebuilt pumps have modern bearings & seals which do not require it. You do need to use something other than pure water with a modern bearing. Anti freeze or water pump lube additive works fine.

Moss type rebuilds have a heater tap that is a pressed in integral tube. As you know, originals are threaded for a screw in shutoff valve tap.

The non valve rebuilts work perfectly well, just not concours correct.

If you want the original threaded type, & your valve is in good condition, several places such as Bill Bolton will reportedly rebuild your original type pump. I'm sure that either arrangement must be available on your side of the pond.

Two of the three original water pump securing nuts are long extension types which make it much easier to get a wrench on them. If you don't have these, it's worthwhile to find a couple,
D
 
HI Dave,

Thanks for the info on the heater valve - I'll make enquiries with the UK suppliers rather than just order online. I'm using a 50/50 antifreeze/water mix so I don't think it's a lack of lubrication problem. I do remember though when running fifties british cars in my student days that water pumps seemed to be a consumable item!!

I'll look out for the long nuts too.

Rgds

Mike
 
A recommendation for when you fill up the system again. Antifreezes have changed considerably in the last decade.
I recommend you purchase either Daimler/Chrysler or a Honda/Toyota antifreeze to install and replace what you've got in the cooling system. Flush it and refill; these antifreezes have less abrasives, more lubricants and are a lot better than just plain "green" antifreezes.
 
A bit of feedback:-

The new pump is in and working fine. I bought the replacement pump from Dennis Welch. It came with an extension tube fitted, which I thought would prevent the fitting of the original heater return tap. On investigation, it turned out that the extension tube was threaded. Once removed, the thread was the correct one for refitting the original heater tap. One problem I had was no puller to remove the pulley from the old pump. After much headscratching I removed it by bolting the fan back on over a small pile of washers - tightening the four fan bolts pulled the pulley off far enough to undo the fan and repeat the process with a small socket under the fan. It took three iterations, packing out a bit more each time. Another problem was that the thread on the front of the pump shaft was different from the old one, and the new nut was a nyloc type which was thicker than the original. so when I came to offer the fan back on to the pulley,(on the car)ther was insufficient clearance between fan and radiator. Loosening off the radiator mounting screws and encouraging the radiator forward a fraction was enough.

The above may be of interest if you are like me and not a trained mechanic with a fully equipped workshop.

Rgds

Mike
'56 BN2
 
While in this case it was obviously the water pump that needed replacement, another cause of a water leak at the front of a 100 is failure of the water jacket blanking plate found next to the water pump. Replacement parts are steel but when I suffered this failure many years ago I found the plate was alloy and it had literally eroded away. This leak will not be intermittant, when the plate fails, IT FAILS!
 
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