Brett & Tiana wrote:

I've just recently replaced all three seals in my (12A) metering pump. I
found that the shaft seal that had been put there months earlier by a

friend

was leaking again.

It was a new neoprene seal of the same 1/4" OD and 1/16th" cross-section

as

mentioned previously, but only held up for two weeks before leaking

again.

This may have been exacerbated by the fact that I'm running 2-cycle oil

from

a reservior rather than the heavier 4-cycle oil from the pan.

On the advice of another RX7 guru I switched to a metric size Viton seal
(marginally larger OD, not certain of actual OD in mm), which was a

slightly

tighter fit. I also replaced the old and brittle end cap seals using

Viton

13/16" OD X 1/16" cross-section o-rings. (Yes, they will conform to the
diamond-shaped seal grooves on the pump body.)

Almost  2 months later there is no sign of a leak. Hope this helps.

Brett,

I pulled my 12 A metering pump apart recently and will replace those seals -
thanks for the heads-up and the info on those sizes.
George (down under)

 
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