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MG MGB Technical - Fan fit MGB

I have now got my engine model sorted and with advice from members, it is a 64-67 build MGB 18GBUH15081.
So now I would like to know if a 12H4744 7 blade plastic fan will fit straight on to the water pump on this engine, I think the pump is a GWP114 (been told but not confirmed).
Any help appreciated

George Mills

As far as I'm aware the fans are all interchangeable, if nothing else pumps and fans changed at different times meaning that each fan was generally compatible with at least two pumps, and vice-versa, through all the variations.

The only thing you have to watch is the differences between short-nose and long-nose pumps, in some case both types can be used with certain engines. Short-nose pumps need a shallow pulley and a spacer between that and the fan. Long-nose pumps need a deep pulley and no spacer. With the wrong combination, and depending which way round you mount the fan, it can foul the block or the rad.

Turning the fan round does not alter air flow direction of course, only reversing rotation direction of the thing that drives it can do that. But some fans have the mounting base offset to the blades, in my case I had a short-nose pump with no spacer, and the fan was the wrong way round to clear the block. There is a slight improvement in efficiency with the fan rotating correctly, but IME it's marginal.

Thanks Paul that's great
George Mills

While all the Bolt holes and spigot align, the plastic fan is thicker, and will be too close to the radiator for comfort with the gwp114 pump. One quick stop a D you might be looking for a new radiator if your car lacks the positive fore/aft restraint of the early convertibles
Paul Walbran

Maybe why one or two packing strips AHH6320 were added each side at various times between radiator flange and mounting panel.

Engine restraints very valid though. Several cars I've worked on should have had the angle brackets on the front mount but didn't, including my own, since added.

The angle brackets were nowhere near as effective as the bellhousing stay, seenquite a few radiators lost by the brackets jumping over the mounts.
Paul Walbran

This thread was discussed between 22/03/2018 and 25/03/2018

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