Car dies when in gear

[80vette_ca]

Hey guys, my car is ideling great and under WOT it runs fine but when i put it in gear with the engine warm or cold the RPM drop to around 500 and then if i just sit there the car eventually dies. Under normal driving sometimes its fine other times it just wants to pop and sputter and then die out. Think this sounds like just a vacuum leak or maybe carb problems. Its a 350 bored 0.30 over running a holley 750, edelbrock intake and aluminum heads, 1.6 roller rockers with crane energizer 284 cam (512 lift), full MSD ignition system. Anybody got ideas for me to check out, thanks

 

[80vette_ca]

some troubleshooting

So i did some checking for vacuum leaks and couldn't seem to find any, I played with the carb and still no affect, adjusted the idel screws and then played with the floats, one thing i did notice is when i take the sight plug out of the front (I'm assuming the main) fuel bowl i can't see any fuel in there with the engine running. when i go to adjust the adjustment screws on top of the bowl, fuel squirts out of the screw and nut but still i can't see anything in the bowl, does this sound right?

 

[wishuwerehere82]

Sounds like the float is adjusted too high if you can't see any fuel. If there was no fuel, it wouldn't be running.
It's hard to see the level if it's too full.
Turn the screw clockwise until you see the fuel level drop in the bowl, then adjust it to the proper level.
Then go back and adjust the idle speed, and idle jets.
It may take few times back and forth to get the idle right. Refer to the carb setup instructions for proper order to follow.
Make sure you set the minimum idle speed with the transmission in drive, not neutral.

 

[JohnZ]

The screw doesn't affect the float level - it just locks the adjustment; the HEX NUT does the adjusting; clockwise to lower the fuel level, CCW to raise the fuel level. Just loosen the screw enough so you can turn the nut; one flat of the nut changes the fuel level by about 1/16" in the bowl.

 

[80vette_ca]

Thanks guys i'll see about adjusting that float level but any ideas about why the car is dying when in gear, RPM drops and then eventually dies out unless i rev it. I have the idle RPM set at around 850 RPM in park.

 

[minifridge1138]

Were there any computer controls on the 80?

Does it die in gear if your moving, or only when you're in gear and at a complete stop?

the more details you can provide, the better our ideas will be.

Good LUCK!

 

[80vette_ca]

There's no computer on this one, the car will die if i let off the gas while driving normally, same with at a stop, only way to keep it running is keeping my foot in it. Only guess i have is a vacuum leak, i'll keep you posted

 

[yellow77]

If you removed the sight plug and couldnt see fuel, the float level is too low, this will cause all sorts of problems. Loosen the screw very slightly, and turn the hex nut counterclockwise a small amount. You will probably have to alternate between the screw and nut until fuel just barely dribbles out of the plug hole. When this happens, lock it down and that float is set.
The same applies for the rear float level.
Let us know what happens.

Cheers

Richard

 

[minifridge1138]

The fact that you didn't see fuel sounds like the float bowl is too low.
Adjust that first and see if the problem goes away.

If it doesn't, try disconecting and plug all of the vacuum lines. If the car dies with the vacuum ports plugged, then vacuum leaks are not your problem. If it runs with the ports plugged, then reconnect the lines 1 at a time. Check to see if the car dies after each line. When the car dies, you'll know which line has the leak.

Good LuCK!

 

[80vette_ca]

Vacuum leak fixed now tunning the holley

Hey guys so here's what i found out, i went around sprayed WD-40 on all vacuum connections and seems to make no affect, so be frustrated I decided that maybe it was something around the carb leaking, So i went around checking the carb bolts and found a couple had worked there way lose so the base gasket wasn't sealing. So i took them all out, and the gasket cleaned everything up nicely and then tightened everything up. Then i tightened up some of the vacuum connections around the back of the intake manifold... put a vacuum gauge on and i'm getting around 10-11 Hg of vacuum at idle and around 7-8 in gear, the car now idles perfect when in gear and drives without dying. Now i have to play with the float a little bit which is fine, and then need to play with that holley a little bit cause its got a hesitation from part to WOT. Question, what are you guys running for jet sizes in your carbs? I looked and i've got 70 in there right now, seems maybe a bit big.