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Old 10-11-2009, 12:05 AM   #1
Scootin 81 C20
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Exclamation Guys, I Need Your Help.

Hey guys, I just went out to start my truck to move it to the garage. I started the truck and noticed that it is starting rougher everyday. Well it started and I heard it backfiring and running choppy. My parents were out in the back yard with the dogs and they told me to kill it because it had flames coming out of the exhaust when it backfired. Here's what I need your help on. What can I do to diagnose and fix this. I have noticed it running rougher for the last week and yesterday on the way home it was cackling louder than usual. So please guys, I really need your help as this is my daily driver.

P.S. If this post doesn't make sense, I'm really shook up right now at the fact that it may be something seriously wrong that I don't have the funds to fix.

Thanks
Benjamin.
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Old 10-11-2009, 06:00 AM   #2
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Re: Guys, I Need Your Help.

When you say starting rougher, do you mean it is hard to start as in taking longer than usual?

It sounds like your timing is off. That could cause both problems your having. It would either be a problem in the distributor, or the chain jumped a tooth due to wear.
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Old 10-11-2009, 10:51 AM   #3
Scootin 81 C20
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Re: Guys, I Need Your Help.

When I say starting rougher, I mean I have to crank it a time or two more than usual and when it starts, it runs rougher than he// for about 10 minutes and then it starts to smooth out.
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Old 10-11-2009, 10:56 AM   #4
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Re: Guys, I Need Your Help.

I agree it sounds like a timing issue to me.
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Old 10-11-2009, 01:57 PM   #5
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Re: Guys, I Need Your Help.

I second wut pcwillsie said check tha timing it sounds like that might be it!!!
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Old 10-11-2009, 04:41 PM   #6
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Re: Guys, I Need Your Help.

Well guys, my dad and I adjusted the timing both directions at the distributor and no dice, now it won't even start and stay running. It is puffing white smoke when it backfires and it occasionally puffs back in the carb. What can/should I do know?

To quote Cooter from the Dukes of Hazzard episode Days of Shine And Roses. "I don't know whether to fix it bury it."
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Old 10-11-2009, 07:05 PM   #7
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Re: Guys, I Need Your Help.

Did you allow it time to warm up? It sounds like a choke problem more than anything else to me, espically since it is now getting colder. Check your choke settings, is it working properly?
If your really worried check your oil for any water since its puffing white smoke, but I believe the problem is with your choke since this problem started all of a sudden.

Tom
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Last edited by Eyegore; 10-11-2009 at 07:06 PM.
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Old 10-11-2009, 07:08 PM   #8
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Re: Guys, I Need Your Help.

Pull the ignition module and have it tested at Advance Auto or whatever you have there.
I am not certain it's your problem, but it won't cost you anything but time to check it.
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Old 10-11-2009, 07:29 PM   #9
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Re: Guys, I Need Your Help.

Quote:
Originally Posted by Eyegore View Post
Did you allow it time to warm up? It sounds like a choke problem more than anything else to me, espically since it is now getting colder. Check your choke settings, is it working properly?
If your really worried check your oil for any water since its puffing white smoke, but I believe the problem is with your choke since this problem started all of a sudden.

Tom
Tom, both my dad and I checked the choke and it is working and it is adjusted for winter. I left it that way from last year.

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Pull the ignition module and have it tested at Advance Auto or whatever you have there.
I am not certain it's your problem, but it won't cost you anything but time to check it.
I'll look into that. When we were messing with it, it bit my dad, but he said it didn't bite as hard as it should. Just to clarify, the module is bolted inside the distributor housing, right?
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Old 10-11-2009, 07:37 PM   #10
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Re: Guys, I Need Your Help.

When was the last tune up?
How do the terminals on the dist cap look?
Rotor?
How do the plugs look? (pull them all to inspect)
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Old 10-11-2009, 07:53 PM   #11
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Re: Guys, I Need Your Help.

To me it sounds like the choke is a big part of the problem. Have you tried starting it and then pulling the choke open a bit to see if it smooths out. Start it with the air cleaner off and make sure the choke pull off is pulling the choke open a bit once the engine fires.
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Old 10-11-2009, 08:46 PM   #12
Scootin 81 C20
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Re: Guys, I Need Your Help.

Quote:
Originally Posted by SCOTI View Post
When was the last tune up?
How do the terminals on the dist cap look?
Rotor?
How do the plugs look? (pull them all to inspect)
The last tune up was a year ago. The terminals were corroded on the cap and rotor so I cleaned them, until I can afford new ones. The plugs are nasty and smell like fuel so they are drying out tonight and I'll try again tomorrow. I'm gonna do a complete replace of plugs, wires, cap, rotor, coil, and module. Just to be on the safe side.

Quote:
Originally Posted by sierra4x4 View Post
To me it sounds like the choke is a big part of the problem. Have you tried starting it and then pulling the choke open a bit to see if it smooths out. Start it with the air cleaner off and make sure the choke pull off is pulling the choke open a bit once the engine fires.
We tried that and it was trying to fire, fired, but wouldn't run. If I can just get it to run good enough to drive a one-way, 20 something mile trip to Whiteside Area Career Center where I can put it in the class shop and work on it, I'll be happy. Once it's there, I can put a Sun scope machine on it, run a timing light on it, and use the schools discount on NAPA parts.
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Old 10-11-2009, 08:52 PM   #13
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Re: Guys, I Need Your Help.

Quote:
Originally Posted by Scootin 81 C20 View Post
The last tune up was a year ago. The terminals were corroded on the cap and rotor so I cleaned them, until I can afford new ones. The plugs are nasty and smell like fuel so they are drying out tonight and I'll try again tomorrow. I'm gonna do a complete replace of plugs, wires, cap, rotor, coil, and module. Just to be on the safe side.
Your heads are likely leaking oil past the umbrella seals & valve guides. This allows oil to drip down into the cylinders which starts degrading plug quality much faster than a vehicle that is in 'fresh' operating condition (no leaks).

All it takes is poor combustion & presto, fouled plugs. Fouled plugs = increasingly poor performance (operation). The fuel smell is two possibilities: a) simple result of multiple attempts of getting the out of tune motor to fire up (typically accompanied w/excessive pumps from the gas pedal when there's already fuel saturation; b) leakage from the carb itself.

Swap out all the ignition stuff ASAP. How old are the plug wires? What size? Stock HEI? What p/n on the plugs? Get one item remedied (the tune-up) & it will allow you to decifier the condition of the other (carb).
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.

Last edited by SCOTI; 10-11-2009 at 08:56 PM.
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Old 10-11-2009, 09:08 PM   #14
Scootin 81 C20
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Re: Guys, I Need Your Help.

Quote:
Originally Posted by SCOTI View Post
Your heads are likely leaking oil past the umbrella seals & valve guides. This allows oil to drip down into the cylinders which starts degrading plug quality much faster than a vehicle that is in 'fresh' operating condition (no leaks).

All it takes is poor combustion & presto, fouled plugs. Fouled plugs = increasingly poor performance (operation). The fuel smell is two possibilities: a) simple result of multiple attempts of getting the out of tune motor to fire up (typically accompanied w/excessive pumps from the gas pedal when there's already fuel saturation; b) leakage from the carb itself.

Swap out all the ignition stuff ASAP. How old are the plug wires? What size? Stock HEI? What p/n on the plugs? Get one item remedied (the tune-up) & it will allow you to decifier the condition of the other (carb).
Ok, I'll let my dad know that. It's gonna cost me $100 for all the ignition stuff. The HEI is all stock replacement as are the wires I believe. They are only about 1 1/2 years old. The P/O included the brand new ones with the truck. I'm gonna get the $15 Auto-Zone wires when I do the tune up.
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Old 10-11-2009, 09:44 PM   #15
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Re: Guys, I Need Your Help.

Quote:
Originally Posted by Scootin 81 C20 View Post
Ok, I'll let my dad know that. It's gonna cost me $100 for all the ignition stuff. The HEI is all stock replacement as are the wires I believe. They are only about 1 1/2 years old. The P/O included the brand new ones with the truck. I'm gonna get the $15 Auto-Zone wires when I do the tune up.
Use AC Delco stuff on the ignition (cap, rotor, plugs) & use 8mm wires. You should be able to pick that up for $50.
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
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Old 10-12-2009, 01:40 AM   #16
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Re: Guys, I Need Your Help.

if all the plugs are fouled chances are its rich. the obvious place to look is to make sure the carb isnt just dumping fuel which could have a few causes depending on the type of carb. if you have a holley a bad power valve will cause exactly what your describing. other carbs and including the holley could also be float adjustment. most likely the carb could have a bad float that sunk.you need to use a timing light to set the timing back to where it should be first of all but it will be obvious if you look down in the carb while its running if its dumping too much fuel. a piece of trash stuck in the needle and seat can also cause it. it sounds like its running ridiculously rich to me and i would look in that area first before replacing anything else. it will be the cheapest fix
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