Fuel pump - aircooleds

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Mech fuel pump wear and delivery problems

mike the van: Having a few probs with the running on my 2.o l A/C, it is pretty standard apart from Twin Dell 36's

Has been running fine, but seems to be lacking a bit of grunt on the hills and the top end has dropped away

Seems almost like when going up a hill it almost shudders keeps going, but usually a change down is needed, temps all seem OK

Any ideas , I have retimed with a strobe to 6 ATDC. But still having problems!

jason k: induction leak?

check inlet gaskets as these are a common fail on dells

mike the van: Seems to be worse under slight load, although I am thinking maybe the induction side as has gradually developed and I didn't use the thick gaskets

orangebooboobearcrew: Could be the start of fuel pump push rod wear - common problem (see my other posts).

This could be starving the carbs of fuel if worn and particualrly when going uphill / under load....

Loads on here about it if you do a search... :ok

Electric fuel-pump (substitution)

cumbriankeith: I used a facet but a more basic one - one up from the very smallest I think.

This is the one - no point in fitting a higher pressure and volume than you need - CUs are only 70 odd BHP after all


Facet pumps from www.raceparts

Use a rubber cotton reel to mount it just behind the tank outlet on the chassis rail and it won't be as noisy as some people think these pumps always are. Looks like you can choose the size of the tails connectors with that eBay supplier - I'd go for the smaller ones - they will be closer to what is already fitted than the 8mm supplied as standard. said

For the record I fitted Facet fuel pump type 40105 Replaced fuel pipe and left old mechanical pump in place.

Installed relay unit with prime push-button and for safety the relay unit senses the alternator warning signal and if absent de-energises relay. Approximate cost for bits £70 including new fuel pipe.

'Many thanks for the help from Fritz and work done by cumbriankeith.

Covkid: - Connecting relay for pump to alternator trigger wire is nice and simple but clearly if alternator isn't working/running, the pump will not run either. This shouldn't be a problem unless the alternator actually fails but if you have an alternator where it takes a rev or two to put the ignition light out, remember, if light is on, no fuel whatsoever is going to the carb and you will quickly run out of petrol once float bowl/s are empty, sometimes just a matter of yards after you pull off. Its therefore important to ensure ignition light is off before you pull away!

If you do experience this problem, in an emergency you can simply clip a wire from battery positive, out the door and underneath to positive on the pump. This will quickly run the pump, fill the carb, and get you running again. Just rev up to extinguish ignition light this time. Ask me how I know all this....

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Topic - Fuel (pressure) regulator