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Discussion Starter #1
I am trying to help a friend get a new car he bought running. It's a 39 Chevy 4 door sedan with a 327 in it. It has an Edelbrock 1406 carb on it, and I cannot keep it running when it is put in gear. I did an online search using the words car stalls when put in gear, and EVERY ONE of them has an edelbrock carb!!!!! The car was bought and driven into the garage, but the car idled really high. I have since gone through everything on it (over the phone) with him since he is Florida. Things I found so far. The 4 and 6 plug wires were crossed, and there was no ground wire on the choke coil. I assume this was the cause of the high idle. So with that being fixed, he got it started and set the timing at about 14 degrees. Now the vac advance was hooked to the passenger side port, though I believe for this car it should go to the driver side. Regardless with the vac advance connected or disconnected, at 14 degrees it should idle. He can idle it at 800 and it is really smooth, the throttle response is really good, and it runs at about 170 sitting in the garage. Now whenever it goes into gear it stalls. I thought maybe it was lean at idle so I had him check the mixture screws and the passenger one was bottomed out. He opened both to about 2 turns but no change. He has raised the idle to about 1100 and tried to feather the gas to barely keep it running. I told him to plug every vac port he could find and see if there was a change. There was none. Only things I can think of is a base plate vac leak, but the car idles so well at 800. The other thing is I wonder if the coil is bad. He killed the battery by leaving the key on, so I don't know if it fried. IF anyone can give me any idea, it would be greatly appreciated. Thanks.
 

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Carb

Edelbrock has compleat instructions on how to set up, repair and you can down load instructions on there web site. Edelbrock.com, they have a teck part if you need to ask a question, Good luck
 

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IS the motor stock. I had this problem when I put a higher horsepower engine in my car with the stock torque converter, same as you describe, dies as soon as you put it in gear, but will run with a high idle. Edelbrocks are goods carbs should run and easy to tune. Take a look at this.

 

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Re-baseline

I'd re-baseline that carb using Edelbrock's instructions.

The butterfly may be too far open at idle (not adjusted right).

start from scratch, but get the timing right FirST!!!


Find TDC on the car and make sure the pointer is AT 0 or TDC. Then set initial timing at 12 and start her up.

Total timing needs to be checked too. 36-38 total timing.

I always advance it as much as it likes, shut it down for bout 10 minutes and try to start it again. If starter drags, i pull it back just a hair at a time until it starts right up when warm (after 10 min shutdown). This is a great place to start for initial timing. Then you need to make sure the total timing is right.

THEN

work on the carb with the timing set.

Just my .02
 

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a vacuum gauge might help diagnose the issue or maybe the carb needs rebuilt. Just thinking outloud.
 

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Like the other member said make sure the throttle blade arent open to far as this will make you lose control of mixture at mixter screws, also make sure there is no debre in CARB
 

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Discussion Starter #7
I am assuming stock converter. He has been told that it is a stock 327 with a cam of the famous "one step above stock" specs. Though there is no cam card or info. Like I said the car did run before, just not really well. So I can't see it being converter / cam related. I believe it is more related to the engine being set up as a bandaid to cover the poor running of it. And setting the engine to run normally is just not allowing it. He did a compression check on it last night, and got numbers from 130 to 160. So the engine is no race engine, but they are consistent and I would guess it rules out valves being held open. I told him before he goes any farther, to replace the plugs, wires, and coil. He pulled all the plug wires off one at time last night and claimed no change when he pulled 4 wires and a big change when he pulled the other 4. So I am starting there. I also did find that the engine has 3947041 heads from about 68-70 on it that should have a gasket type plug and there were tapered seat plugs from like a late 70's car in it. Thanks so far.
 

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Timing, timing, and once again timing!

What you describe is most likely not a problem with the carburetor. :no:

Make sure the advance weights and springs are fully operational and that the vacuum advance works properly and is connected to a full manifold vacuum source. (driver's side)



Always set the initial timing with the advance disconnected and the vacuum ports plugged.
 

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Discussion Starter #9
Thanks guys, I know this is hard to help with. Like you I am only able to go by what he tells me. I did tell him about the driver side port on the carb yesterday. However, he claims that vacuum advance connected or not does not change the base timing. But regardless the car should idle with the vac advance disconnected. He tells me he has at least 14 initial in it at 850 rpm in neutral. This should be more than enough to get it to run. If he told me 4-6 degrees, I would say bump it up a bunch. He has tried 1100 rpm idle and 14 degrees base timing and it stalls going into gear. This engine is so mild that it should run with 8 degrees and 800 rpm idle. If I was there, I would put a timing tape on it and bump the initial up to 20 and set the idle at 1000 and see if it worked. If it didn't there is no way it is timing related.
 

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Not that it matters but I was told to use the passenger port timed. If he has an automatic and it stalls when putting her in gear then I would think its carb related.
Also, the vacuum advance shouldn't make a difference wether its working or not if he not getting to idle n gear, the vacuum advance doesn't start working till your actually driving or getting the rpms to come up. As rpms come up, vacuum hg drops which then alters timing.if he can't get it to idle then its not working whether it works or not. Lol isn't there like a kick down cable in automatics that changes the idle circuit when put into gear? Sounds like its loading up and I thiink the carb needs gone through. And if he has the wrong plugs then he's gonna definately fix that.

Is the exhaust plugged? Sounds funny but id look to see if someone stuck a banana in there. Lol has he put good gas and replaced fuel filters and is he getting good volts when he's trying to idle? Was the tranny shifting smooth when he did get to run it?
 

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Ii still think if he plugging vacuum advance in he'd do it in the port above the throttle blades. In have a non emissions set up and I've heard some cars like the other but I would think you wouldn't want constant manifold vac to the vac advance. Either way this isn't the problem. Good luck keep us informed
 

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Need to check manifold vacuum with the engine idling. This will be a big help in further diagnosis.

Also need to verify that the outer ring on the harmonic damper has not spun on the inner hub of the damper, thus rendering the timing mark inaccurate.

Also need to verify that the engine has the correct combination of timing indicator and harmonic damper. Generic "one size fits all" timing indicators are common place for the SBC, and are wildly inaccurate in many cases.
 

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Can he have someone in the drivers seat and put it in gear while he sprays a little carb cleaner in the carb to see if it stays running. If so it's lean and he may try and turn mixture screws out another turn or 2 see if it helps. If the carb cleaner keeps it running but the mixture screws don't help, pull the carb top off he'll probably see debris inside.
 

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Discussion Starter #16
No, I tried eveything I could think of. Either the carb is just bad, which is possible. The car gets horrible mileage. Or the issue is converter related. We ran timing up and down all over the map. Verified vac advance was not pulling in at idle, verified mechaincal was pulling in at idle. Tried full vac advance with a ton of initial. Every time it went in gear it fell right off. Later on he told me that at a light the car feels like it wants to pull through the light and in gear idling it will go like 15 mph. The engine wants to get back to the 1000 rpm idle. It is just being pulled down in gear. That is why I believe it is in the converter.
 

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Yeah maybe the converter is just too tight for the setup? Must be a super tight stock converter with a really low stall speed.

Don't larger displacement engines with more torque generally make the same converter stall higher than a smaller displacement engine making less torque? A mild 327 probably isnt kicking out much torque at low RPM's, so maybe it has a mismatched converter installed in the trans? Maybe its a stock 12" converter from a larger V8 engine and the lower amount of torque from the 327 is causing it to stall at a lower speed?

I dont know maybe I'm way off on that, but if you've nailed down the timing and carb adjustments and its still doing that it sure seems like that could be it.

There's no vacuum leaks right? I think you mentioned you guys checked for that already.
 
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