Fuel Filter and Pump Recommendations with conversion from FI to twin carbs

Just converting to twin Webber 40s.
Fuel tank appears to have no gauze on supply pipe (FI tank)
So I wanted to run a decent filter before my elec pump.
Tried with the OG type FI filter but after running ENG for about an hour or so whilst tuning my carbs the pressure dropped right down to almost nothing. And filter bowl on Malpassi nearly ran dry!
Think I may have knackered the pump too!

Presumably filter is too fine for a low pressure pump.(filter was new and still yellow!)or maybee something blocking the inlet of my tank!
have now fitted a metal Mann WK 512 filter Before my Facet Flipper pump

anyone else using this set up / Mann metal filter ok with carbs?

thinking I’m probably gonna replace facet pump with hi press pump + regulator with return to tank.
Does anyone have any other/better recommendations?

cheers for any info just hoping to get a useable system for now as going away tomorrow and don’t have time to buy anything on a Sunday!

 

Hi there I'm just in the throws of setting mine up, where is the fuel pump located? What pressure were you achieving at the malpassi filter? Whats type of facet pump are you using and whats its pressure/flow rating?

Last thing have you a safety solenoid cut off installed?



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Fuel pump is in original vw location next to rear outrigger on rear cross member, pump is low press 2.5 to 3.5 psi. To start I had 3.5 psi static (ENG not running)and carbs were flooding.dropped it to 2.5 all was ok then suddenly whilst tuning it dropped to almost nothing! Was definitely the filter as herd bubbles in tank after changing it.
And no cut of yet other than via electric relay when engine cuts out.

 

What’s a Facet Flipper pump? Don’t use a high pressure pump with carbs, it doesn’t make sense to drop the pressure down through a regulator when carbs only need a low pressure. I use a CB/Carter rotary pump that doesn’t need a regulator.

A Mann WK 512 filter should be fine and the FI filter should also have been okay. The problem is elsewhere – is there any fuel in the tank?

 

X2 for Carter rotary pump. Pumps at 3psi and built in filter too.

 

Not sure where you've located the pump from description but it needs to be under the fuel tank to get gravity to feed it as it pumps fuel and doesnt 'pull' it

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yes that’s what I thought initially regarding high press pump.
will prob go carter pump now instead just wanted regulator and visible filter to be able to monitor condition of fuel and to confirm what pressure out put is.

 

I put mine here

Then took the feed pipe in through the nearside of the engine.

 

Van back up and running now and pressure ok. Think it was either an air lock or pump overheated due to cavitation!
Filter looked ok but may have been blocked internally? Tank looks ok apart from a very small layer of rust at bottom. Think it’s just had a verry good clean of 20 of yrs of Dirt out since filling it up a few times!
Hopefully Mann filter will be ok , also have a spare for the trip.

Cheers guys ....fingers....crossed

 

Those worm drive hose clips on the pump and filter are far too large and will damage the hose.

You could fit the Carter pump where the original FI pump was and there really is no need for a regulator it’s just something else to go wrong – and what can go wrong will go wrong, it’s just a matter of time.

 

Incidentally, what was wrong with the FI? Backwards step changing FI for carbs, unless you’ve changed the cam.

 

Yes will be ordering new clips just ran out and fitted what I had left plus old FI hose was 10mm between filter and pump! And yes may well remove filter king or move it somewhere else as not really keen to have it in engine bay!
Changed to Carbs as Although it ran ok before the breakdown I just didn’t have confidence in it and felt it All needed removing and overhauling. At least I can play with / Fix carbs if something goes haywire!

 

Fuel filter seems ok! 200mile round trip to sunny Dorset went well with no major problems. Still need to move Malpassi filter as it seems to take ages to prime where it is (probably air due to being high up on fuel tank bulkhead and long pipe runs as pump still in stock location)
Thinking of putting it below van on chassis rail near pump.

 

The fuel filter shouldnt empty out if the fuel pump isnt running. This means you have a small leak somewhere in the fuel system, probably up around the Malpassi unit or the carburettor. Air leaks in when the pump stops and the pressure drops, when the pump is running the leak will be very slow, as air is less viscous than petrol, and you are only looking at a few ml of air getting in over hours, the same rate of leakage going the other way will just evaporate ...

The other thing you could do is use a fuel shutoff solenoid - it would stop petrol running back too.

 

Or just get rid of the Malpassi filter and route the fuel hose direct from the pump to the carbs.

 

Hi all. I'm installing a fuel cut off solenoid with Mapassi filter king and facet pump.

Does anyone have pictures of a set-up drawing of where to locate and wire each part?

Cheers

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Yep must be getting in somewhere, think also part of the problem is with the pump being in the Original stock location. After having a quick google Most low pressure pumps will only Pump to about 12”/30cm Head, chassis cross member is probably twice that! Will be fitting a shut of solenoid but right next to tank outlet.
So it’s either move pump n ditch Malpassi, or fit higher pressure pump?

 

If it won't start straight away it's likely the carbs that are empty. If there's fuel in the bowls it would run for long enough to refill the pipes and you'd never know.

 

Looks like you have mounted the Facet pump horizontally. They should be mounted at an angle with the outlet higher so it can self purge any cavitation bubbles.

 

Malpassi filter is now gone!
van always started fine and ran ok but pump just struggled to fill filter bowl that high up, tried moving it to lower location but I still didn’t like all the Pipes /wires connections rubbing against each other.
Problem I think was that as soon as engine shut down the fuel in filter back tracked to the tank causing a syphon to occur emptying bowl to about the level of fuel in the tank.
pump was then struggling to fill filter back up and also pressurising the air gap in top of filter bowl.
So to work properly it would need at least a NRV or fuel shut off valve.
However Seems to be ok plumbed straight thru with no carb bowl leaks at idle so far.....Time will tell.
And yes although pump isn’t at an angle which I overlooked (as I just fitted it to existing rubber mounts from FI pump) it is still at lowest point Both ways with probably 18” head of pressure to tank above it but I’ve not run it below 1/2 tank of fuel yet as gauge was sill reading reserve when 1/2 full.
It’s still on it’s limit of 12” Dry prime height so will probably change it for something better with a nrv built in.
I could just move the pump Higher but I like the fact It’s easy to replace Where it is, even it at side of the road if need be and it’s not in the engine bay either!
I suppose I could even fit 2 pumps .....