Elec Fuel Pump

[Super Jamie]

i'm putting a little clacky electric fuel pump in my ke25, i'm just trying to figure out a place to mount it. the instruction say something like "engine bay bad, next to tank good", so engine bay is right out (but the stock pump is there?)

 

so far i've found out that i should mount the plastic pump to the body with rubber mount points (stewart just cut up some old radiator hose) and i should give it some air space to aid in cooling

 

i could mount it in the boot, next to the tank on the wheel arch or the parcel shelf support or behind the back seat, however this would be loud in the car, and i'd have to cut the factory aluminium pickup hose which i'd rather not do

 

i could mount it under the floor, and make a plate to go over it to protect it from rocks and stuff, there's actually a nice little tucked up bit next to the leaf eye where i could put it. this would also make it alot easier to factory in a return line (just tee it in before the pump, as opposed to returning to the tank). i think i'll do that

 

opinions? here's a pic of the underside

[wilson_610]

In general, a pump in any circumstance will run better and last longer if it can PUSH the liquid rather than trying to suck it. so somewhere in the back near the tank will be the best thing

[Medicine_Man]

Fuel pumps don't suck, they pump, if they run dry you will kill them, thats why you also run a lifter pump, the lifter pump sucks the fuel from the tank to feed the fuel pump..

[mikeys toy[RL]]

aftermarket pumps do not suck fuel; they push it. You will need to mount the pump BELOW the fuel level for it to last and work properly.

as for the return line; you should run it back to the tank to give it a chance to cool before bieng drawn into the carb, this will aid in vaporlock problems

Edited April 29, 2005 by mikeys toy

[demuire]

Clacky pumps like the one Jamie has are lifter pumps.

[mikeys toy[RL]]

ya, i hate those, i've never had one go more than 10,000 mi

i always would use one off of an old honda, subaru, or the best were the early rx-7s; those were a vane style pump

[styler]

yeah well u get both types suck and push, personally i got myself a little inline pump which can be used as a lift pump or booster pump etc. even though its self priming / lifts fuel (sucks fuel) it isnt really designed to do it as its main function, as has been said its designed to push, so its best to mount it as close as possible to the tank and as much below as possible.

 

my pump, pierburg inline "3-7" psi was easy to put in and cost about $80 from supercheap. its loud when it primes but goes quiet after. it has a little regulator in the engine bay adjusted to 3.5psi. i think a good regulator would be a speco one for about $40. i think they are rising rate too.

 

it doesnt run a return which seems to be common, i am gonna hook one up though cos once my car was left on ignition and the pump died not surprisingly! or somehow connect the pump wires so it only runs when the car runs. i think the return is a good idea cos i see air in the fuel filter sometimes and a return should eliminate the air problem.

 

it was easy to mount being inline and used standard 1/4 inch fittings unlike other pumps which would have to be modifed to 1/4 inch. and it came with all brackets and mounting hardware/rubber vibration insulator. and self priming meant almost

no chance of dying. i think its a vane type. i have put a little inline fuel filter between the tank and the pump.

 

at the wreckers you can find some old small elec pumps - ie low pressure high volume in certain cars, like in early efi cars, but meh too much effort and time compared to a new one with all the bits included.

 

most of you know all this lol but it should be a good read anyway for other people

 

i'll get some pics of the setup if anyone wants em i'll email them.

Edited April 30, 2005 by styler

[Medicine_Man]

My 4AGE will be fed with an in-tank lifter pump that feeds the surge tank and a fuel pump to keep the fuel up..

[demuire]

Jamie running carby, don't need high pressure pump like your 4AGE!

[Super Jamie]

wow, piersberg pump for 80 bucks, that's pretty damn good! my carby guy recommends them too, he thinks this little thing i have is pretty crap. but rob and stewart use similar things so it should be fine. oh well, if it dies it dies and i'll get a piersberg then

 

got a Z200 fuel filter, they're a high-flow efi filter with 8mm fittings, so i'll mount that between the pump and the tank, then make up an alloy plate to cover the lot

 

got a little 12V relay, which i'll probably switch from the ignition coil, or if i get really adventurous, i'll splice a wire in the steering column. i'll hopefully be able to run power to the pump along the same path as the tail-light wires

 

thanks everyone for your help, this has been a very eductional experience :D for anyone changing from stock to electric pump, factor in $200 including all hoses and fittings and plates and bolts and everything. it's probably cost me a tiny bit over $150

 

now i'm off to put my car on ramps and drill holes thru the floor :D

[coln72]

If you are going to use your car in competition with an electric pump then, according to CAMS, you will need to have some form of cut out so that in case of a crash the fuel pump stops if the engine isn't running. CAMS don't want fuel being pumped over hot exhausts of shorting electrics.

 

In my case the pump is hooked up via the oil pressure sender - no oil pressure no pump. Not strictly by the recomendations but it works. CAMS suggests using a cut off swith (impact sensor??) from a LPG vehicle to do this.

 

Then again, I have not been required to prove that I have complied yet..........

 

On the pump side, I am running a Facet pump under the boot floor to feed my twin aisans with no return line. Tried a Holley Red a long time ago and pissed it off as it kept starving for fuel. The car would just stop until I sucked fuel through the system. After this I went back to a Facet.

[Super Jamie]

how does an impact sensor work? obviously you crash and it goes open circuit. but how does it tell the difference between a crash and say, a speed hump at 40mph?

 

how is your oil pressure switch hooked up, just a relay off the idiot light wire?

 

i think the likelihood of me entering a CAMS event any time soon is unlikely, but i'd like to set it up properly from the word go. most racing requirements (bonnet pins on pre-72, fire extinguisher, etc) are a good idea for a normal car anyway

[Super Jamie]

ahh that makes sense, thanks :D

[coln72]

Your right, the oil pressure switch controls a relay which operates the pump. There is a manual overide to prime the system for starting (if required).