1954 Mercury Fuel Issue

[Fairlane56]

1 week ez start on mine. 2 weeks 3-5 pumps and hope it catches, 3 weeks or longer crank 15-20 seconds or remove air cleaner and add fuel in carb bowl. I blame the ethanol blend fuel…. Worse in California with summer blend.

[KULTULZ]

Dave is correct in his description.

Here is another problem(s) with just a primer pump -

1) The pump needs a filter in front of it so as not to ingest any fuel tank trash and lock/burn it up ...

2) A mechanical pump does not like inline filters on the suction side and can lead to vapor lock/ fuel blend separation, etc.

3) The pump is going to draw a lot of AMP and the OEM IGN SW and wiring is not going to like it. You need a BAT RELAY FUSED source and sufficient wire gauge to get AMP to the pump.

4) The pump should be on a by-pass circuit as shown below. The install is not correct as there is no ELECT PUMP INLET FILTER installed.

And of course I cannot find the ILL ...

... i'll be back ...

OK ... I am back ...

[paul2748]

You don't need a by-pass circuit - just a electric pump that has a flow through feature.


See https://www.ctci.org/vapor-lock-and-...ic-fuel-pumps/

[KULTULZ]

Originally Posted by paul2748

You don't need a by-pass circuit - just a electric pump that has a flow through feature.

See https://www.ctci.org/vapor-lock-and-...ic-fuel-pumps/

Originally Posted by KULTULZ

Here is another problem(s) with just a primer pump -

1) The pump needs a filter in front of it so as not to ingest any fuel tank trash and lock/burn it up ...

2) A mechanical pump does not like inline filters on the suction side and can lead to vapor lock/ fuel blend separation, etc.

That is why a PRIMER PUMP should be on a BY-PASS CIRCUIT.

One must ascertain FLOW-THRU RATING before purchase of the pump. On a BY-PASS, there is no need for a FLOW-THRU RATING.

[JMFL36]

I don't see the need to put the auxiliary electric pump on a by-pass circuit. The pump I bought is flow-thru and my stock mechanical pump pulls like a clydesdale. I'm going to use a momentary switch wired to a battery power source, which eliminates the need for a relay and for wiring through an oil pressure switch and the ignition circuit. Just a simple flow-thru primer pump with 2 wires, ground and power through a momentary toggle switch (with an in-line 3 amp fuse).