Finally It Runs . . .
I Finnally Started up my 77 Vette, But all i can let it Do is Idle, as soon as I Tap the Gas it will Stall. I Checked teh Timing Countless Times And Its Dead on Perfect.
What could be Wrong With it?
Ps. I have to get it Fixed by this weekend :cool: :cheers:
Btw, What Should i set timing @ For Best Performance and easy Starting with the Mods Listed in the Sig,
Also What Rpm Should it Idle at?
I really need help with My Originall Question First though :(


Are all the vacuum lines hooked up? Is your vacuum advance connected and working. You said your timing is dead on, but that is at idle. What happens when you try and speed it up? Does the distributor advance like it is supposed to? There are two types of advance, mechanical and vacuum advance. Mechanical advance is controlled by springs in the distributor. Vacuum advance is controlled by car vacuum actually moving the points (or pickup) plate around the distributor cam.
If the timing isn't advancing it can keep the car from running.
When I First Put the NewCarb and Intake on it Fired Right up and Ran preeety Good. The Car is not a daily Driver so it Sits a lot, So i only work on it in my Spare Time. In the Meantime the Starter Died on me, so i replaced that the other day and started the Car right up. It idles Decent but as soon as I even Tap the Gas The Car Stumbles and Chokes and wants to Die Donw and Stall.
The Distributer is Vacum Advance, I tried it with the Vacum Connected and Disconnected and still got the Same Crappy Results :(
The Carb is Also New and Worked Perfectly when I installed it. (no other Adjustments were made)
What could it Possibly be? :confused:
Sounds like you have a big vacuum leak somewhere. First thing to do is double check your carb installation. Make sure the carb is seating against the gasket as it should and against the intake mounting surface. Are your sure you're using the correct carb gasket? Are you sure all the unused fittings on the carb are capped or plugged? If you have a vacuum gauge (if you don't, borrow one) check your vacuum at idle. Should be at least mid to high teens. If you have an automatic trans, make sure you've hooked up the vacuum modulator hose.
1) replaced plug wires
2) replaced plugs
3) replaced master booster(had a major vacuum leak there...I am seeing a connection w/what the other guy posted above)
4) replaced fuel filter
plus the big one
5) when I first fired up my car, it was after a 6 year dry spell of just sitting, so it ran like crap, I went out and let it idle every day for about 30 minutes while I watched my FAV TV show or did homework. THen I'd go out and rev it and hold it at different RPM's for about 4-5 minutes total. after two weeks it was running good, I had a friend come over and he said it looked and sounded like everything was in perfect condition for sitting for 6 years.
I don't know what to suggest though...sounds like the vacuum leak probably.
Daniel
Well I am Running with the PCV valve Bypassed. would that Cause it not to run under throttle? (It ran Fine Before)
Im Gonna T the Pcv valve into the Vacum Stream and see how that works, I also going to test the vacum pressure. whre should i hook the Vacum Tester up to? :confused:
The Best of Corvette for Corvette Enthusiasts
I also hooked up a Vacum Guage/Tester and it was Far under the Teens where you all said it Should be. The Guage was Bouncing around like there was no tomorow.
What could be Causeing all of this?
Btw, I hooked the Vacum Guage up to one of the Vacum Lines going into the Intak manifold/Carb.
My '69 has only 9" at 750 rpm and goes quite well so don't worry about the absolute level of the vacuum.
Check for accel pump shot when you blip the throttle.
there should be a nice stream of fuel into each side of the carb
Check float levels while running
Check fuel pressure while running
Timing isn't THAT critical, anything from 0 to 20 degrees and it should RUN!
Do you have points? :U make sure of the dwell if you do
I would bet tho that it's fuel related
Try this...
SLOWLY increase the engine speed till it starts to die, then squirt a little starting fluid in the carb ( just a pinch!) if it takes off, you definitly have fiel problems, if not look to that bouncing vacuum ( check compression ) or the ignition... use a timing light and look for a steady flash...
Because, The Shortblock is New , as are the Heads, intake ,Carb, and ignition.
Im gonna try and Spray some gas down the Carb and see what that does, If that is my Problem, what do i need to do to fix it?
I would like to have this thing Running by Saturday. (Woodward Dream Cruise) :cool:
If the car does start and idle then pouring gas down it will do nothing helpful.
A bouncing needle on the vacuum gauge in your situation is indicative of an improper carb adjustment or an intake (vacuum) leak. If your carburetor accelerator pump puts out any kind of stream at all, the engine should rev. It may have an off idle sag or stumble, but it should not stall when you open the throttle, especially with no load. When you hooked up the vacuum gauge, it's not all that important where, as long as it's downstream of the throttle plates and is exposed to full engine vacuum. The fact that your vacuum is low and erratic certainly seems to indicate a vacuum leak. Take a few minutes and pull the carb and check the imprint on the intake-to-carb gasket. There should be a clean crisp outline of the carb base on one side and the manifold flange on the other. If not, find out why. I agree with the poster who suggested checking the dwell if you have a points-style distributor. If push comes to shove, run a compression check. It's just difficult for me to believe that an otherwise healthy engine would die when you open the throttle just because the accelerator pump was weak. BTW, if you don't have one in your private library, the public library has a copy of the Chilton's repair and tuneup guide that has a troubleshooting section that will help you evaluate your vacuum readings. Sorry if it seems like I'm harping on vacuum, but it just seems to me to be the most likely problem, given what you've told us about your engine.
So now im thinking that my prob is not Fuel related , maybe it is Vacum .
I just cant figure from where, all the Gaskets on this whole motor are brand new :(
Pull the top off of the carb. Like 8 star bolts. see if the bowls are dirty on the bottom. That carb is a good design that all gaskets are above fuel level so it won't leak and you don't have to worry about the gasket.
You think this is bad put a Holley on it and you will have all sorts of joys.












