Question about 1986 305 carbed firebirds
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Question about 1986 305 carbed firebirds
Hi,I have read online that 1986 and 1987 carbureted firebirds have both a mechanical and electric in the tank fuel pump,supposedly this was to combat vapor lock and heat related issues,my question is this,if the electric fuel pump fails,will the mechanical pump still allow the car to run? The electric pumps are notorious for being a pain in the *** to replace. I am hoping these cars simply use the electric pump as a helper and can run without it. Can anyone confirm this is true?
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From: Sebastian FL
Car: 87 firebird 86 c10 90 mustang
Engine: 383 sbc
Transmission: 97 t56
Axle/Gears: Moser 12 bolt 3.73
Re: Question about 1986 305 carbed firebirds
I'm not sure but you could probably look and see if it has more than 2 wires going into the tank from the forward side of it and you'll know theirs something besides a gauge sender inside.
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Re: Question about 1986 305 carbed firebirds
My question wasn't about if it has an electric fuel pump in addition to a mechanical one,according to what I've read they do have two pumps because of heat related issues.
My question was if the electric one in the tank fails will the car still be drivable with nothing but the mechanical fuel pump on the engine block like any normal carbureted car.
My question was if the electric one in the tank fails will the car still be drivable with nothing but the mechanical fuel pump on the engine block like any normal carbureted car.
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Joined: Dec 2016
Posts: 187
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From: Sebastian FL
Car: 87 firebird 86 c10 90 mustang
Engine: 383 sbc
Transmission: 97 t56
Axle/Gears: Moser 12 bolt 3.73
Re: Question about 1986 305 carbed firebirds
I only have a mechanical pump but removed the intank pump. You can pull through a electric pump but it will really decrease the volume you could get through. May only be a problem if you really want performance or go WOT for a good run. I only mentioned checking for fuel pump wires to see if you didn't need to worry about it.
Joined: Mar 2000
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Re: Question about 1986 305 carbed firebirds
To the best of my knowledge, '86 only had the electric pump if a customer complained about vapor lock, and the dealer installed it as part of a vapor lock kit.
L69 also had the in-tank electric ('84 & '85).
But only the '87 LG4 had the in-tank electric from the factory.
As mentioned, a non-functioning in-tank will reduce the capacity of the mechanical. Best to get the electric running.
L69 also had the in-tank electric ('84 & '85).
But only the '87 LG4 had the in-tank electric from the factory.
As mentioned, a non-functioning in-tank will reduce the capacity of the mechanical. Best to get the electric running.
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From: Perth Western Australia
Car: 1987 Z28 Camaro
Engine: 305 LG4 4bbl
Transmission: TH700R4
Re: Question about 1986 305 carbed firebirds
Five7 is on the money with the years and options.
its a mixed bag on the effects though. if she dies in the tank, the mechanical may have no issues pulling fuel through, it may create a partial restriction that makes you think the fuel filter could be clogged or it may stop fuel flow all together.
but as above - best to get the electric running
its a mixed bag on the effects though. if she dies in the tank, the mechanical may have no issues pulling fuel through, it may create a partial restriction that makes you think the fuel filter could be clogged or it may stop fuel flow all together.
but as above - best to get the electric running