Connecting electric fuel pump

[47windsor]

I am going to install an electric fuel pump  in line on my 47 chrysler 6 .  My only question is the power source. Looking at the ignition switch I have selected the terminal that has only one wire attached (brown) which is going to the ammeter, would this be a suitable source tha twould only allow the operation of the electric fuel pump if the ignition is on?

 

Bruce Watson

[JACK M]

The ammeter is hot all of the time on both sides,  If you hook it up to the ammeter it will run whenever the battery is hooked up.

I would tie it in at the coil. I guess it could be hooked up on another side of the ignition switch, but it would be easier at the coil (same thing)

Also, on a recent project that was a Henry J with a 6 volt system we had trouble with the electric fuel pump off setting the float needle.

(Some previous owner put it on there)

We put one of those in line regulators on it set at 3 lbs. to fix that problem.

What is wrong with the original pump? Or are you just hooking it up for initial priming?

[47windsor]

Jack, Thanks very much for your reply, I will use the coil contact at either the ignition switch or directly from the coil.  The electric fuel pump is only to be used for priming. Like most of us the cars aren't started everyday or even every week so it makes it less time for the starter to crank over & of course saves the battery.

 

Thanks for your help

 

Bruce W

[Gunsmoke]

When I installed an in-line electric pump on my '31 Chevrolet, based on a recommendation from an old timer, I also put in a toggle switch so I could relieve the pressure to the carb by shutting the pump off a few seconds before I shut off the car. In my case the old fuel pump at the time was toast. I have since rebuilt the old mechanical pump and taken the inline pump off, don't really need it any more. 

[Ttotired]

Just an often not thought about precaution with using electric fuel pumps

 

You really should wire it through an "engine running" system that has a priming timer function on it/in it

 

Main reason for this is in case of an accident, you do not want the fuel pump running continually with the ignition key on and possibly pumping all the fuel out (broken fuel line or car upside down)

 

Just while I was typing this, I thought I would do a bit of a search to see if someone made an aftermarket type of module to do this, seems that they dont?

 

Fuel injected cars normally have this protection built in as a function of the electronics (ECU or body control module) and also an inertia switch

 

I am a bit surprised that my search was not that fruitful, might be something worth looking into

 

I did note that your talking about using it just to prime the engine, but this is a protection against forgetting to turn it off (A push button switch also stops this ) or if the mechanical one fails and you use the primer to get you home

 

Mick

[Spinneyhill]

Batteries are cheaper than engines.

 

When the car has sat for a while, the oil drains away. The first start takes a while to pump it all back out again. So for engine longevity, the little extra grinding is beneficial to pump up the oil pressure before it starts.

 

In my opinion, forget the electric fuel pump, make sure the original works well and remember you are pumping up the oil pressure during those infrequent starts. You could even get a maintenance battery charger (so called Smart charger, about an amp max.) for when the car is sitting. This is what I do.

 

Another option, which is what is in my car until my Round-To-It comes round to making up an original pump, is a somewhat modern fuel pump with a hand priming lever on it. No farting about with electrickery this way. Having said that, I rarely use the hand pump. I usually grind it for 5-10 seconds with the ignition off after it has sat for a while; it reduces the mechanical noises just after starting.

[Guest]

The Vega used a switch connected to the oil pressure in the block.  No pressure no current would flow.  I think it would be easy to put a connection in the oil filter line and to screw one of these in there.

[Ttotired]

Oil pressure switch is good, provided the engine will achieve enough to activate the switch while cranking

 

Most will, but thats what the timer side is for, it will activate the pump for a few seconds, then shut off

 

If the car goes upside down, no oil pressure, no fuel pump and if you put an inertia switch in it, a big thump and also no fuel

 

But again, a push button switch to prime is very unlikely to stay on (does happen though), causing any dramas in the case of an accident

 

Mick

[TerryB]

Motorcycles with FI systems use fuel shut off switches too for the electric pump in case the bike is in an accident or falls over. One of their sensors might work in an auto system too.

Terry

[47windsor]

Thank you all for your input it is greatly appreciated.

 

Regards

 

Bruce Watson

[JACK M]

Are you using this as a replacement or as a priming pump (recommended)?

For priming put a push button on it so you wont forget to turn it off. The original pumps worked ok for all these years and I don't recommend replacing with electric.

[47windsor]

Jack,

 

The idea of the electric fuel pump is for priming.  After saying that if something did happen to the original pump the electric, one would get me home. I have opted to have a toggle switch with a red light to indicate it is in the on position.

 

Appreciate your input..

 

Bruce 

[JACK M]

Jack,

 

The idea of the electric fuel pump is for priming.  After saying that if something did happen to the original pump the electric, one would get me home. I have opted to have a toggle switch with a red light to indicate it is in the on position.

 

Appreciate your input..

 

Bruce 

 

Good idea with the switch and light.