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[C2] Started running like crap

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Old 07-12-2018, 08:56 AM
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prestige6
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Default Started running like crap

Went to Cruise night last night. Took the 67 427-435 ran great going there. Was about 25 miles away.. Coming home was running great . Came to a detour when I slowed down, would night idle. Had to keep playing with the gas to keep it running to make it home.. Any ideas where to start. Thanks
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Old 07-12-2018, 09:24 AM
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Tampa Jerry
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Check the usual suspects.l would start with checking to see if you have a clogged fuel filter or dirt in the carb. Check the needle and seat. Check the big red wire feeding power to the car on the outside firewall. If it is loose or the connections are dirty, this will cause your problem. Check your timing to see if the hold down slipped. Also check your points to see if they are opening and closing and in range.Check your alt. to see if it putting out 14 plus volts. It could also be vapor lock. This will give you a start. Jerry
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Old 07-12-2018, 09:51 AM
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This has happened to me three times over the years.

First was the choke snapped closed on the small block Chevy in my 1954 Studebaker when I stopped at a stop sign - went pig rich, had to keep feathering the gas to get home, but easy fix.

Second, some asswipe twisted the mixture adjusters on the front of my edelbrock carbs (twin 600cfm carbs on a tunnel ram Chevy 502) in my 1941 *****ís when I was at a car show. This is probably not your issue and one of the reasons I donít like Edelbrock carbs with their big, easy to turn knurled adjusters.

Third, was crap in the fuel tank of my 1970 442 convertible with a 455. It ran great and then started missing and bucking. If I let it sit, it would start right up, but then in about ten minutes do it again. It was a bitch to find, but when I did I felt like a genius!

Only the first is potentially your issue, but your symptoms sound more fuel related than ignition.

Best of luck in the troubleshooting and please let us know how you resolve it.

Last edited by Factoid; 07-12-2018 at 09:53 AM.
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Old 07-12-2018, 10:25 AM
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Gavin65
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You have a triple carb set up and normally run on the center carb, did you try kicking in the outer carbs? see if the performance is there or not, I would start with replacing the fuel filter may have pulled some dirt into the carb., it really does not sound like an ignition issue.
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Old 07-12-2018, 11:18 AM
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I think you need a better definition of crap to get a good answer.
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Old 07-12-2018, 12:19 PM
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Originally Posted by Factoid View Post
This has happened to me three times over the years.

First was the choke snapped closed on the small block Chevy in my 1954 Studebaker when I stopped at a stop sign - went pig rich, had to keep feathering the gas to get home, but easy fix.

Second, some asswipe twisted the mixture adjusters on the front of my edelbrock carbs (twin 600cfm carbs on a tunnel ram Chevy 502) in my 1941 *****ís when I was at a car show. This is probably not your issue and one of the reasons I donít like Edelbrock carbs with their big, easy to turn knurled adjusters.

Third, was crap in the fuel tank of my 1970 442 convertible with a 455. It ran great and then started missing and bucking. If I let it sit, it would start right up, but then in about ten minutes do it again. It was a bitch to find, but when I did I felt like a genius!

Only the first is potentially your issue, but your symptoms sound more fuel related than ignition.

Best of luck in the troubleshooting and please let us know how you resolve it.
Its clobberin' time....

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Old 07-12-2018, 12:55 PM
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Factoid
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Oh, believe me if I would have caught him red handed...

...this was back when I lived in PA and it was a huge show at a fairground with over 2,000 cars.

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Old 07-12-2018, 01:02 PM
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Originally Posted by MikeM View Post
I think you need a better definition of crap to get a good answer.
Going very rich Wanting to stall. I could here and feel a definite miss. I'll go out in a little while and see how it starts up cold now.
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Old 07-12-2018, 01:07 PM
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Originally Posted by prestige6 View Post
Going very rich Wanting to stall. I could here and feel a definite miss. I'll go out in a little while and see how it starts up cold now.

Pull the sight plugs on your float bowls and see if gas runs out after you turn the engine over a few times. Watch out for sparks off the coil.

Last edited by MikeM; 07-12-2018 at 01:24 PM.
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Old 07-12-2018, 02:22 PM
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Was it acting rich or fuel-starved? Vapor lock feels very much like running out of gas but you can often keep the car moving by "feathering" the gas pedal and nursing the car a while.....sometimes that too will eventually stop working; sometimes you can power through the condition and resume normal driving...
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Old 07-12-2018, 03:08 PM
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Originally Posted by Frankie the Fink View Post
Was it acting rich or fuel-starved? Vapor lock feels very much like running out of gas but you can often keep the car moving by "feathering" the gas pedal and nursing the car a while.....sometimes that too will eventually stop working; sometimes you can power through the condition and resume normal driving...
I believe it was running really rich when it was starting to stall. Only when coming to a stop. I would put the car in neutral and apply the brakes on a slight roll so I wouldn't have to come to a complete stop and keep the car running by giving it gas. Once I got rolling again it was running decent but not 100%. I just went out No plug wires off. Before I started it, I was able to move the Dist. Now I don't know if it moved before then. I reset the timing and really tightened the dist. down. checked the float level of the center carb. That was Ok. Adjusted the carb. It was running good after I reset the dist. Do you think it could be vapor lock?? Oh by the way Frank, It was my self adjuster hanging up on the 63..
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Old 07-12-2018, 03:31 PM
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Originally Posted by prestige6 View Post
I reset the timing and really tightened the dist. down. checked the float level of the center carb. That was Ok. Adjusted the carb. It was running good after I reset the dist. .

How far was the timing off? Could have been your problem if it slipped enough.

I'd check the float levels in the end carbs too.
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Old 07-12-2018, 03:59 PM
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Check the distributor rotor ! Kidding. But maybe NOT! I had that symptom in my 66 427 a couple of years ago, suddenly, and after checking EVERYTHING else, I pulled the rocker covers and found a broken valve spring.
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Old 07-12-2018, 06:28 PM
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Originally Posted by prestige6 View Post
I believe it was running really rich when it was starting to stall. Only when coming to a stop. I would put the car in neutral and apply the brakes on a slight roll so I wouldn't have to come to a complete stop and keep the car running by giving it gas. Once I got rolling again it was running decent but not 100%. I just went out No plug wires off. Before I started it, I was able to move the Dist. Now I don't know if it moved before then. I reset the timing and really tightened the dist. down. checked the float level of the center carb. That was Ok. Adjusted the carb. It was running good after I reset the dist. Do you think it could be vapor lock?? Oh by the way Frank, It was my self adjuster hanging up on the 63..
Hard to say but a rich mixture usually results in some black smoke and sooty plugs. Pulling a plug might give a clue. Hearing so much about vapor lock in the current heat wave that just seemed to be a likely candidate.
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Old 07-12-2018, 06:59 PM
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Originally Posted by prestige6 View Post
Going very rich Wanting to stall. I could here and feel a definite miss. I'll go out in a little while and see how it starts up cold now.
I would check for a fouled plug. Easy to check and will show if it is rich also.
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Old 07-12-2018, 07:33 PM
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prestige6
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Default Runs like Crap

I was thinking of putting the Phonolic plates between the carbs. They come in 1/4 inch and 1/2 inch. Has anyone done this with the Tri Power?/ Will I have a problem closing the hood??
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Old 07-12-2018, 09:15 PM
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If all else fails, I would look at the center carb float. I had one fail (sunk) creating a gross rich condition.
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Old 07-12-2018, 10:58 PM
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I'll 2nd what claf said.

On my small block single 4 barrel Holley (2818-1) I went through this loading up condition which repeated itself after double checking and setting the primary float level. Unless I was running WOT, she would load up and die. Pulled the primary bowl off, removed the float and it was full of gas! �� This was a brass colored float. What was happening was she ran Ok initially, but once she was fully warmed up, the pin hole in the float opened up from the heat enough to fill with gas. The float adjustment just went out the window when that happened as the now heavy float just called for more fuel, running like crap, rich as hell. That cost me a lower end rebuild.

Worth checkin that out.

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Old 07-14-2018, 09:50 AM
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I'm going to pull the carbs off, and install phenolic 1/4 inch plates between the carbs. Also check the center carb float, Change the fuel filters. The car runs a little rich when running good. What jets are suppose to be in the center carb? How many sizes should I go down to make it leaner???? Thanks
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Old 07-14-2018, 10:21 AM
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Did you check the float levels in the end carbs?
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