oooooook so im posting, again, for my 1984 camaro, 2bbl 173 cu. in. 2.8L backed with a 5spd, all orginal. now when i got the car the mechinical pump was bypassed with a aftermarket electir pump, just chilling in hte engine bay. well got a new fuel pump(mechinanical), new gas. old gas has been tooken out. fuel lines are clear. when we pour gas into the carb it runs but when the gas runsout it dies. so new fuel filter. still dies. took the line off from the pump to the carb and nothing! nothing at all, in fact the line was bone dry and still looked like it did when i put it on there. went to the boys at advance and they say the cam shaft is worn. thing is ive never heard of something like that. so is it that? or is there something else? please help, all help is welcomed and thank you in advance.

p.s. to any one who says get a v8, you have to buy me one and ill glady put it in!

 

Go buy a $20 electric, but it should be installed as far back as possiable, they are meant to push, not pull.

 

I dunno, but if your Advance auto guys are anything like mine.. DON'T listen to them.

 

advance boys said the same thing. i really dont want to tho. but looks like i mite be, thanks.


ya theres like 3 stores here and 2 of em are complete idiots and the third store, half the staff are morons. but the guy i talked to seemed like he knew his stuff but still i dont. im gona rebuild it with performance anywas so guess ill find out then huh lol.

still would like to run mechinical, any other ideas?

 

Check to see that the actuator arm is actually moving when you turn the engine over by hand. It is possible that the cam lobe is worn, but highly unlikely. It could be that the old pump was bad for so long that the arm is stuck or something, I suppose. Either that or the strainer sock in the gas tank is crapped up bad enough that the mechanical pump can't suck anything through it, unlike the electric.

And yes, the parts store guys are idiots. When my 730 ECM failed the second time (at first thought it was the ignition module that went bad), I went to have it tested at AutoZone. When I had the ign module tested, I saw the test harnesses and the directions (for the 730) in the book they have there. But, when I went to have the ECM tested, I was told "Oh, no... We can't do that! There has been so many revisions we could never possibly test THAT! But we can sell you a crap reman one for $75 plus tax!" I looked at the guy, said to myself, "that's a load of bullcrap if I ever heard it!" and went to the junkyard to pick up another one from his pile (the one I'm running now... Only ever had 2 from there fail out of four, one with a bad fuel pump relay circuit and the other got soaked)

 

so the eletric is more powerful? and the strainer should be fine, bc thats how i siphined out the old gas. and this arm you speak of? where can i find it and how do i check it?

 

just a thought but wouldnt a electric pump have to much fuel pressure compared to a mechanical pump? so youd need to get a fuel pressure regulator too im guessing right?

 

no the $20 pump they sell are for carbs, FI fuel pump are not $20.

 

i wondered the same thing

 

The actuator arm is what converts the eccentric cam to a vertical up-and-down motion that moves the diaphragm inside the fuel pump. At least, that's the way the SBC is. If it's not there or if it's stuck or the cam is worn, you won't have a working pump because the diaphragm isn't moving.

But, hey, if the electric works, use it.

 

o ok so thats what the advance guy was talking bout, lol he said to stick a finger in there and try to start it, but to greese the finger and not put it all the way in, just close and should feel pressure...i thought hell no im not doing that, and im not finding some one who will. but i didnt think to try it by hand. so ill do that some time soon, maybe sunday. what if i can feel it moving? does that mean the cam is worn? and ill be using an electric pump till this is fixed...but i still hate it.

 

I'm replacing my mechanical for an electric and had a question. The Mechanical one has two lines on it. One from the tank is the main fuel line is the other a return line????? If so, what do I do with it if I put an electric back by the tank? Should I also install a relay for switching off and on or??? Last question, do I need the oil pressure safety switch? If so will any work?

Thanks..........

 

ya thats what i had to do. i had 3 lines bc i have ac. but ya the return line just leave open. i hooked a toogle switch bc the pump i got can be used as a booster, so then when i rebuild this motor ill have a booster but the electric ones manual says to hook it up to the igniton switch and youll need a fuel filter b4 the pump and a fuel regultor, o and a 5amp fuse. oil saftey switch... theres one on a mechinal pump? hell theres one of those on these cars period??

 

Thanks for reminding me about the fuel filter before the pump I forgot about that. I was going to wire it to the ignition via a relay. The oil safety switch is incase you blow your engine or worse it reads that the oil pressure is low or 0 and shuts off the pump other wise it will keep on pumping gas thru the carb and that could be real bad if you crash etc. Just wondering if any here has used one or not? The mechanical one will stop with the crank so no need for one.

 

ya and i dont believe our cars have a oil safety switch bc on my 88 fi the oil sender kept popping out lol. and i guess its a common thing so i dont believe any of our cars have one, but i mite be wrong. just post a theard or search most ppl here are happy to talk bout it.

 

The sender n oil switch are two different things, GM used them on everything as a back up, so if you had oil psi [via cranking] it would turn the FP on as a default backup if the regular system was not working.

 

o ok thanks for the info/ correction

 

Gumby, your 86 was like my 87 used to be. It has a separate oil pressure sender and switch, whereas the later models have an all-in-one thing that has 3 wires. IDK if my switch side is working or not, but I think the sender side died because my gauge hasn't worked in 2 months now...

And no, mech pump cars don't have the switch, as there is no need for it. When the crank and cam stop, so does the pump.

All you have to do is remove the pump from the engine and try to move the arm by hand to see if the pump will pump gas into a container or something. If it doesn't, the diaphragm is shot. If it does, either the arm isn't being moved by the cam or the fuel line between the pump and the carb is clogged.

BTW, do some of those carbs use that screwy inlet filter, or are they too new?

 

ya so ive been told to do. and idk bout all carbs but mine has that screwy filter. lol i remember when i was at the part store they gave it to me and i was like ummmmmmm what the hell is this? i dont think its the right one. and they where yep it is, where the fuel line goes into the carb the should be a bigger nut thing closer to the carb then the fuel line is. i was like dam.