80smtn

Hi Guys,

After sitting for a couple of days, my carbd 86 305 with Edelbrock takes about 20 seconds of cranking to get fuel to turn over. Drives great after that with no problems all day long. I do understand this is a common problem with todays fuels and evaporation.
Questions:
1. Does my car solely rely on a mechanical pump at the block or is there another pump in addition in the tank. I hear no humming when key is turned.
2. would adding an inline flow through style pump near the tank to push some fuel up be helpful at all?

Thanks very much,

John

OrangeBird

iTrader: (1)

Hi John , Here is your wiring diagram . In the upper right area you will see your fuel pump wiring , there are two fuses , a relay , the oil pressure switch and the pump itself involved in the circuit . check the fuses first and then take voltage checks at the relay while turning the key to the crank position .

PS , at the "crank" fuse disregard where it says "Hot at all times" , it's actually only got power when the key is in the crank position , hence the name "crank fuse" . Damn typos ....

mmadden55

mechanical pump at the block and adding an electric won't make a difference. On mine I just crank it 10 seconds, pump the accelerator pedal three times, and hit the key again fires right up.

80smtn

So does this mean I have both a mechanical pump at the block and an electric pump in the tank? Is this a typical symptoms of the tank pump not working, but the mechanical still working?
Thanks

John

midias

Because someone hacked on an edelbrock carb the only way to know your fuel pump setup is most likely to look. Who knows what else they did.

If you car sits for a while the fuel bowls in the carb can go dry and the line can drain back to the tank. Because a mechanical pump is engine driven you will have to crank it over a bit to refill everything that is normal

mmadden55

An 86 with a carb should not have an electric fuel pump. Unless it started out with fuel injection., I assumed it did not since it has a carb on it now and you did not hear a fuel pump come on. So no you do have both.

OrangeBird

iTrader: (1)

This statement is in error , yes indeed the OP's 1986 with carb (Vin G) did have both a mechanical pump and an electric in tank pump , just as the wiring diagram posted in post #2 of this thread shows .....

zed-028

If he does have an in-tank pump then this would be indicative of said pump shitting itself.

80smtn

Thanks for all the great reply's. OrangeBird is correct and the wiring diagram confirms it. I am in the process of sorting through the wires and fuses and relay's. I can't seem to get the case off the fuse to check it. Any thoughts?
Thanks,
John

sofakingdom

iTrader: (1)

That's not a fuse; just a splice. Doesn't come apart. One side of it is probably a fusible link. Probably the right side in the photo. (looks like the "rust" colored rating) Which might conceivably be bad.