Do fuel pumps fail suddenly?

[ScienceBoy]

We were driving around in Harry quite happily a few weeks ago but since we've not been to start him. Diagnosis shows I can get fuel to the pump, but nothing's coming through on the other side.

Do fuel pumps fail like this, or do they tend to be gradual?
I've read other posts about intermittent faults being an indication that the pumps failing.

Before I go electric I just wanted to check the pump is duff or can't be (easily) repaired. Thoughts?

[carver90]

yes, had one just go out of the blue with no warning before. G.S.F sell them around 25 pounds. quick fix. job done.

[kevtherev]

No repairs.. Just replace.
When the diaphragm splits.. That's yerlot

[toomanytoys]

The gsf ones didnt have the inlet and outlets In he right orientation, fouls on the breather tower... worth checking ...

[ScienceBoy]

Or going electric...?

[CovKid]

Go electric. You don't get dry lines if its been stood then. I fitted a primer push-to-make overide switch to mine. Put an end to all that dribbling fuel down the carb throat. You'll need to fit new fuel line though.

Mech ones can fail like that although you usually get bad running problems in the months leading up to it. Both types have their merits ofcourse. Electrric one introduces a new noise for starters.

[ScienceBoy]

Wiring it to the alternator means that if the engine stops, the pump stops. Guess that does away with the need for an inertial cut off?

[CovKid]

Indeed. However, if for some reason the line becomes dry AND engine doesn't start, alternator won't supply power to pump. I fitted an emergency momentary switch to supply power to pump if that ever happens otherwise you'd have to run a wire from battery positive, scrabble underneath and touch positive on pump. Did that a few times in puddles in the rain before fitting switch.

Its a rough & ready solution. Top notch solution would be a small relay and wired to coil or similar but a momentary switch is still a great addition if you ever run out of petrol and need to get the fuel through - or indeed drain the tank.

The Facet pump only draws 2 amps so well under the level actually needed for a relay but some just like relays.

[MGP]

The fuel pump relay from a k-jet injection car runs the pump for a few seconds when the ignition is first switched on and uses a signal from the coil to keep the pump running. Just thinking out loud but it maybe worth looking into.

[bigherb]

The fuel pump relay from a k-jet injection car runs the pump for a few seconds when the ignition is first switched on and uses a signal from the coil to keep the pump running. Just thinking out loud but it maybe worth looking into.

We have
https://club8090.co.uk/forum/viewtopic.p ... 7#p7908387" onclick="window.open(this.href);return false;

[MGP]

I will be over here sitting quietly in the corner if anyone needs me.

[CovKid]

Heres another way using oil pressure: http://www.how-to-build-hotrods.com/ele ... -pump.html" onclick="window.open(this.href);return false;

Lot of messing though - better to fit a relay designed to do the job as suggested by BigHerb.

With the rough and ready alternator trigger I use, its advisable to fit an overide switch but even I concede that at the end of the day a relay is a better solution to avoid dry lines. I'm fairly sure I actually have one at the bottom of my spares bin so will play with that once weather warms up. That said, if you needed to fit an electric pump in an emergency and didn't have the relay, you can use the alternator trigger wire to power it until you can have the time to wire it all up as you'd like.

There are even fully-fledge fuel pump controllers, inertia shutoffs, blah blah. The main prequisite from safety point of view is: Engine stopped = Fuel Pump stopped.

[ScienceBoy]

Got my Facet. Instructions say to mount at 45deg. Did you guys do that?

[bigherb]

Got my Facet. Instructions say to mount at 45deg. Did you guys do that?

Yes
https://club8090.co.uk/forum/viewtopic.p ... t#p7874193" onclick="window.open(this.href);return false;

[CovKid]

I think mine ended up at 45 degrees but not intentionally - it was more the way chassis holes dictated where it went. I've read elsewhere that the angle hasn't mattered but I suppose it'll be related to the way these pumps push rather than suck fuel through.

The crucial bit is the filter. They need clean fuel and won't tolerate any grit through them which is why you have to have the filter in front of it. Mine came with a screw-in one but I used a disposable one on the line instead, figuring that this would be much easier to change over. I also changed the whole line to 8mm hose front to back I think.

One thing I have noticed is that during braking the pump goes virtually silent. Most odd.