Disconnected TAC & runs awful- what did I do?

[Jeremiah]

No problem I think its easier to give a visual for people.. Rather than over there by the thingy that is right next to the alterhuminator..

Did you disconnect the tach wire from the negative side of the coil?

 

[Ski 61701]

If I were you I'd pull the bulkhead plugs apart and examine the the terminals and make sure they are not corroded. If they are clean put dieletric grease in the terminal area and reassemble. Pay close attention to the amp meter wire both inside and outside of the pass compartment make sure the outside if the wire isnt bubbling due to excessive resistance in the wire. Ive cut open what I thought was good wire only to see green corrosion inside. It might behoove you to bypass the amp gauge. If you dont have one you might want to consider getting a factory service manual the wiring diagrams are a great thing to have. If I lived closer I'd stop by to help you out.

 

[65Fury440]

Did you disconnect the tach wire from the negative side of the coil?

I was thinking the same thing, if the green wire is making any contact to metal, you're gonna have problems.

 

[Jim Chochole]

OKay I figured out the issue- its the 750 Holley dbl-pumper. The car sat for a couple weeks and when I went to start it the plugs were fouled out. Gas is getting past the cylinder and exploding in the tailpipe and out the carburetor. Next step, is to replace the wet plugs and get better ones. Darned Holleys!

 

[1967coronet440]

What motor is in your car?

 

[BeepBeepRR]

I can speak from experience. DO NOT GET ACCEL BRAND PLUGS.

 

[Jim Chochole]

My car has an early 70s 400 motor.

 

[1967coronet440]

That double pumper might be a bit much for your motor

 

[Jim Chochole]

I agree but I have a high intake and I would have to swap plates over for a more standard carburetor. Anyone know how hard it would be to swap to an Edelbrock for reliability? Or can recommend a simple carb for swapping?

I have a 400 with a mild cam, m1 intake Holley 750, 727 with 2500 stall. Hp exhaust manifolds with 2 1/2 exhaust.

 

[oldbee]

Ur not gonna like my idea, but 670cfm carb. IMHO

 

[Jim Chochole]

I am open to whatever ideas you guys think is best. What brands do you fellers prefer for a bolt-and-go carb?

 

[oldbee]

I think Eddy wud be a little shorter? Others will chime in.

 

[Jeremiah]

When the car is idling can you see fuel coming out of the boosters, primary or secondary?

Have you checked the float level?

Does it run a mechanical pump?

There is no reason a 750 DP won't run on that, it can be made to run fine on a 318.

 

[Shorthorse]

I have to agree with Jeremiah. How long has that carb been on your car? Has it been running Ok until recently?
I know multiple things are possible at the same time but the odds are high. You first noticed it when you were dealing with wiring that was related to the ignition. If the engine was not firing on all cylinders, you will get wet plugs, not caused by the carb.
It's never bad to consider, where was I and what was I doing last before this started. It's not impossible but be careful about getting sidetracked.

 

[Dragon Slayer]

You did two things. First check that you still have a good ground to the negative side of coil. Depending on how the terminals were stacked, and the condition of the wiring you may not have the ECU connected well to the coil. Go back to that wire on the coil and inspect for good continuity. Did you bump or move the distributor? Is it loose, is the cap on tight.

The second was the manual choke. Did you disturb any of the carburetor linkage? Is the choke functioning right?