> From Darrell Walker <walker@hprpcd.rose.hp.com>:
>
> In reconnecting the fuel system on my 66 TR4A, I have discovered a
> potential problem. When I pump the priming lever on the fuel pump,
> or even crank over the engine with the starter, I can force fuel to
> spray out of the float chamber vent holes (I have HS6 SU carbs).
>
> [...]
>
> Questions-
>
> 1. Is it possible the I have too much pressure from the
> fuel pump? I thought this might be the case at first,
> since it takes a bit of pressure on the priming lever
> to get it to spray (I was trying to test the fuel line
> connections). But it also happens when I crank the
> engine with the starter.
Something's wrong with this picture. You should not be able to make fuel
"spray" anywhere by squeezing on the priming lever. In fact, when the carb's
are fully primed, you shouldn't feel any resistance at all on the priming
lever. The way the fuel pump *should* be working is that pressure on the
priming lever (or the corresponding action from the cam inside the engine)
should draw fuel *from* the tank, and it's the return spring pressure on the
pump diaphram that "pushes" the fuel to the carburettors (and likewise,
determines the fuel pressure to the carbs).
In your rebuild, did you maybe install the check valve backwards??
> 2. Is this a common failure mode for the float valves? If
> so, would groose-jets be better?
No, this is not common. Grouse jets won't help in this situation.
Let us know what you find.
Good luck!
Pat Vilbrandt John Fluke Mfg. Co., Inc. Everett, Washington USA
UUCP: pwv@tc.fluke.COM or: { uunet, uw-beaver, sun, microsoft }!fluke!pwv
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