£1 Fuel Filter

[alantoon]

Should the filter be fitted before or after the mechanical fuel pump,mine is before, the car runs fine but the filter is always half full and I get drainback from the carb when the car hasn't been started for a while.

[tractor]

should be just before carbs

[alantoon]

Cheers, it's been the other way probably since the car was built as the pipework and bracket match the original,work. I have just renewed the filter every year. I think I am just looking for jobs.

[Guest 2b cruising]

Leak back is caused through leaky valves in your mechanical pump.

If you are lucky enough to have a stripable pump you can still buy valves.

[Guest 2b cruising]

Originally mechanical pumps had the fitter before them.to stop muck getting into the valves holding them open and stopping them working altogether.

[knights_templar]

filter should be before anything with moving parts, such as the pump.

 

filters do run partially full, if there was a fault you would have running problems at high fuel demand.

 

provided carb is fitted at correct orientation the carb can not drain back down the fuel system, the needle jet is above fuel level, and therefore can not syphon out.

 

The fuel in the float chambers will evaporate over time, as the float chamber is vented to atmosphere, will just require a little more cranking for the pump to re prime the system.

 

unless you have a running problem, or there is something we are not aware of, you may be looking for something that is not an issue.

[Guest 2b cruising]

I fully agree about leave alone unless you have running problems.

However, before common rail and when the same type of pump was fitted to diesels, I've had to change many vale sets.

No way they would prime back up.

Later in line and rotary spa pumps had a one way check valve to stop this happening.

[maccavvy]

mine seems to need a good few turns over when stood for a whiile..a week plus..

best way i found is a little squirt down each choke from a petrol filled pop top bottle sorts it out.

[Guest 2b cruising]

Can you get a pump at a reasonable cost.

Pinto mech pumps are all getting on now and well worn.

Might save you weeks of messing about trying to diagnose.

Knights is spot on about the float inlet jets, however every carb breaths so fuel level goes down and will speed up the carb emptying.

Easy to remove needle valves and look at the seats.

If worn change these first before the pump.