drex

iTrader: (1)

ok ive been working on this formula for a while now.last summer we ripped a great running aftermarket style 350 and put into a stock 87 formula.the motor was a daily driver, never any problems.i didnt mess with any settings whatso ever.except i pulled the distributor and then put it back after the install and set it.now i have to pump the gas like a mad man to get it to sputter and eventually start.i have the same fuel pump that i was running before.once it does start, the idle will go to 2500 then slowly come down till she dies.lol but in the midst of writing this post, i had a brain fart.QUESTION???the two fuel lines running up the passenger side of the engine bay, one big one smaller, is one of them a vent that i plugged with a bolt.is this plugged vent the cause of poor running?if it is then im an idiot!what should i do with the vent?:hail:

Nixon1

What kind of fuel pump are you running..... An in-tank pump? Is it from a fuel injected motor? Cause those motors run with like 35-40 psi of fuel line pressure, and a carbed motor can't use that. Carbed motors run, maybe 5-10 psi or so of pressure.

drex

iTrader: (1)

its the mechanical pump that has always been bolted to the 350.the formula was 305 4bbl. with overdrive auto.i dont think its anything on the motor but more something i did when i installed it.or something on the car itself.like i said i just pulled the good motor and slid it right into the formula

Nixon1

Oh ok....my fault.

So the fuel tank isn't vented at all right now? Maybe it's vapor-locking?

drex

iTrader: (1)

yes. that would be a definite problem then right.thanks for the advice also.but i did take it on the street when it was still running like this. as long as i had my right foot somewhat on the gas,it would run strong.just very hard to get started,(even when warm) and the idle will be fine for about 4-5 minutes then start dropping till she died?its gotta be something stupid like the vent?the motor was hassle free

ShiftyCapone

iTrader: (7)

Did you set the timing right? You may want to re-check that to be absolutely sure.

RB83L69

Sounds to me like it has a massive vacuum leak. Check the PCV line off the front of the carb, the power brake line, the carb flange gasket, things like that.

I doubt it has anything to do with the pump or the fuel lines.

drex

iTrader: (1)

all of my vacuum's are all connected tight.after this problem i have set my timing everywhere.(cause everyone will give you a different degree for chevys).still doesnt wanna start until you give it alot of gas. when she is running it sounds strong.and it will idle perfect for 4-5 minutes then just SLOWLY drop...really slowly.about 100rpm's a second. my carb could be at fault also but she worked fine before ...what is that little gas line running with the real fuel line?what else could give me a vacuum leak besides the obvious hoses?:hail:

drex

iTrader: (1)

i also have a set of roh snypers....good looking rims.mine are shot

RB83L69

Carb flange gasket, intake gasket, defective brake booster, all sorts of things. The behavior you describe is classic vacuum leak symptoms.

Put the dist back where it belongs and leave it alone. It's pointless to try to tune a defective motor. You can dink with that until the cows come home, and all you'll accomplish is to create extra work since you'll just have to set it back right again once you get the real problem taken care of.

You can check for it by spraying spray-can carb cleaner at liekly suspects, and see if the engine speed changes.

drex

iTrader: (1)

thanks everyone for posting so fast.i can tell im gonna love it here.ill try what you recommended:lala:

drex

iTrader: (1)

i have a few more questions about this problem.the return line with the fuel line...i had left it uncovered and my mechanical pump has no return fitting.now i started it last season a few times, but it still didnt want to stay running like when it was in the other car.i start it up yesterday and the return line is dumping gas all over. it never did this before and i have mabye $3.00 worth of gas in the car.i will try and get a mechanical pump with return.could this be causing me problems....also can you do any damage to a motor by having the firing order mixed up?i dont think so? ill check the vacuum leak ideas tomorrow.i also saw another post where a carbed 305 camaro had both mechanical and electric pumps stock.is this possible and if i unplugged computer would the pump still work.i never heard it if there is one.my motor still needs 20 pumps of gas to even get it to sputter and eventually start.i might also buy a carb tomorrow and see what that does....thanks all

RB83L69

Except for the obvious fire hazard, no it's not particularly a problem.

But, the return is beneficial, because it keeps the fuel circulating; so rather than stacking up in the line and moving slowly and getting heated up, it's always cooler.