Electric fuel pump

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m1marty
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My tercel:: 1986 DLX 4WD 6SPD
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Electric fuel pump

Post by m1marty »

I have searched the forums a good bit on this topic and have not found a clear answer. I would like to delete the mechanical pump and run an in-line electric. questions are:
-Location of pump. In the engine compartment or near the tank?
-Block off plate for mech. pump. I can fab one but, does anyone have a cheap/quick solution?
-Best way to set up regulator/return line. I have seen regs. with a return port or I was thinking of running a tee on the inlet side of the reg. and feeding the return that way.
-IIRC the stock pump runs at approx. 7psi- I was thinking of finding one close to this and getting it dialed with the reg. I do understand that restricting a electric is not good for it so it would need to be close. Recommendations on pumps?
My pump is a bit noisy and the fuel fitler always looks a little low to me while running (about a third full and drops when you gas it- almost like it's not pulling enough fuel) Lines are good and I'm getting a good seal on the tank. Maybe I should just buy a new pump but this one is roughly a year old. Thoughts?
Oh look.......another broken part.
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ARCHINSTL
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Re: Electric fuel pump

Post by ARCHINSTL »

My replacement pump came with a thick (1/4"?) "plastic" gasket; I cannot recall if the OE did or not. I also do not recall (blush) if I used the original or if the replacement came with two...
Anyway, how about just using a flat piece of plastic (even a Tupperware/margarine canister) cut to the size of the gasket and over the OE/replacement gasket, using the OE studs and nuts?

This is an interesting project - ditto with the filter observation - please keep us advised - and costs.
Tom M.
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kamiphloj
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Re: Electric fuel pump

Post by kamiphloj »

I don't claim to be a great expert on this.
Certainly,it can be done
If you have your mind made up that it is what you really want to do,have fun and learn all you can.No disrespect or discouragement intended.
I have bought a fuel pump from Autozone that failed after 2 weeks and left my daughter stranded on a 12,000 ft mountain pass as a winter storm hit her.
However,
A best quality mechanical fuel pump is a very easy thing to install.It is simple and reliable and should probably last as long as your engine is likely to run.
I wouldn't worry about that bubble in the fuel filter too much,does the engine run well? Does it cut out under heavy load? Do you vapor lock?
All it needs is enough.Have you done a fuel pressure/flow test? to set the regulator,you need a gage anyway.Be sure the gasket stack thickness comes out right.This affect how the arm rides on the cam.The terc came with a plastic drip tray doohickey under the fuel pump that adds about 5/32 inch as I recall.
If you do go electric,one common type of pump is a solenoid pump.They are not meant to have a bypass line,the just hold the pressure.(Might be made in Malasia or Borneo or???)
Then typically at your oil pressure sensor you would put in a pressure sensing switch to supply current only when the engine has oil pressure.Why? You don't want the pump to pump when you have a wreck or leave the key on.
Oh,and for real estate to mount accessories under the hood of a Terc,well,there isn't much,and most of the open space is handy when you change oil or a starter....
But still,it is your car!!! Enjoy!!! Bob
Like my old Volvo 544 with 4wd.I seldom regret neversieze or threadlocker
Mac
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Re: Electric fuel pump

Post by Mac »

i think a regulator and metal block off plate will work best, the type of plastic used in a Tupperware or margarine container will melt on the engine.

a tee off the fuel supply line into the return line might work, but your also taking the chance that all the fuel will bypass going into the carb and simply go to the fuel return line.

something you might try would be routing a line from the outlet to the inlet of the pump, if it works correctly you'll have a returnless fuel system and any excess fuel will cycle through the pump until the carb needs it. in theroy it works, but in practice it may be another story. If it works an added benefit will be increased fuel milage because less fuel will evaporate on its way to the hot engine and back into the tank. thats why new cars have a returnless fuel system nowdays.
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mods: ignition at 10 DBTDC and 90 octane gas.
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ARCHINSTL
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Re: Electric fuel pump

Post by ARCHINSTL »

The Tupperware/margarine lid WAS a D'uhhh moment on my part...
As Emily Litella would say - "Never mind!"
Tom M.
T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
takza
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Re: Electric fuel pump

Post by takza »

Nothing in the FSM on gasket/spacer thickness...and with a mechanical pump operation depends on how close the follower is to the cam. My old pump was sticking when cold and would take forever to start pumping...when out...found the follower was riding on the edge of the cam.

Think I used the thick plastic spacer...shield...and a gasket. New one is doing fine.

You might have too thick of a gasket set? I'd pull it and see how it is riding on the cam...you can probably bend the follower to one side if needed. I bought a roll of gasket material at the parts store...not too hard to make a gasket.
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m1marty
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My tercel:: 1986 DLX 4WD 6SPD
Location: Gig Harbor, WA

Re: Electric fuel pump

Post by m1marty »

takza wrote:Nothing in the FSM on gasket/spacer thickness...and with a mechanical pump operation depends on how close the follower is to the cam. My old pump was sticking when cold and would take forever to start pumping...when out...found the follower was riding on the edge of the cam.

Think I used the thick plastic spacer...shield...and a gasket. New one is doing fine.

You might have too thick of a gasket set? I'd pull it and see how it is riding on the cam...you can probably bend the follower to one side if needed. I bought a roll of gasket material at the parts store...not too hard to make a gasket.
I'm going to check that in a day or two. I have the plastic thing and gaskets but couldn't find anything either on correct instalation. I was also thinking I might try and do a return-less system by running a line from the return on the pump to a tee just before the filter. I can't think of any reason why this wouldn't work or hurt anything and it won't take but a few minutes to set up. Cheap too! :D
Oh look.......another broken part.
kamiphloj
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Re: Electric fuel pump

Post by kamiphloj »

Hi,on the gasket stack for the mechanical pump:
The original setup,as I recall has a shovel shaped plastic scoop under the fuel pump with a flange that fit between the fuel pump and block.It defected oil or fuel leaks away from the engine.Replacement pumps provide a plastic spacer to replace this original part.I prefer to retain the original part.
So,I'm pretty sure it goes1)fiber gasket against block 2)original or replacement plastic part
3) fiber gasket 4)pump

I rub a little moly grease on the lever where it rubs the cam for start up.

If you do still go for an electric pump(not my recomendation) carefully consider the wiring.
The solenoid pump draws some amperage.What circuit do you want to use?.Not good to pump gas if you just want to listen to the radio.
Also,consider using the switch at the oil sending unit.It will start the punp at 3-7 psi oil pressure.
Like my old Volvo 544 with 4wd.I seldom regret neversieze or threadlocker
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splatterdog
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Re: Electric fuel pump

Post by splatterdog »

The OE spacer also helps deflect some heat from the exhaust manifold. The cheap spoonless ones that come with a new pump should only be used if the stock one is shot or already gone.
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