Author Topic: MISSFIRE ON ONE CYLINDER ?  (Read 7559 times)

Offline cudaneil

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #30 on: February 08, 2009 - 11:23:48 AM »
The miss is continuous at any rpm. I have checked everything and I am baffled. As I said, increasing resistance by pulling the boot away from the plug induces a spark and the engine runs fine on all 8. This indicates not enough resistance to cause the coil to charge. I have changed plugs & wires more times than I can count. Cap, rotor, coil. I put an entire MSD 6A system in. Still have the miss. :dunno: This is part of the reason I am going to tear down the motor. I figure I will get it in the rebuild, because it is not electrical. At least I don't know how it could be.
My apologies. I didn't mean to hijack your thread. I was just hoping that you might have similar symptoms and we could figure it out between the two of us. :cheers:

Kevin

             I think yours must be electrical, because of the fact you can get the cylinder to fire by pulling the boot away. If it was mechanical,compression or flat cam lobe the
 
             cylinder would not come back on.   Why dont you try going to a garage and getting a SUN/CRYPTON tester or the like hooked up to your motor. That will definitely tell

              you!

                                                                                                 :cheers:  Neil.
« Last Edit: February 08, 2009 - 11:27:53 AM by cudaneil »
just one more job to do..................  (O----{|||}----O)




Offline cudaneil

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #31 on: February 09, 2009 - 06:56:58 PM »
Hi,  update......
                      Fitted new carb base gasket(Holley 4bbl) today.  the motor fired up 1st time from cold. But still uneven at idle

 and when warm, still stalls when drive is selected.    :stomp:   This is so annoying !    The only things i havent changed are

the plug wires and the intake manifold gasket now.

                                                                          Cudaneil   :faint:
just one more job to do..................  (O----{|||}----O)

Offline 340Challman

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #32 on: February 10, 2009 - 11:08:38 AM »
Neil, I think we should get together and have a bunch of pints. :drunk:, sacrifice a few chickens, hire some women to dance naked in the rain and maybe it will all go away.



If it doesn't.....



At least we had some fun.
 :bigsmile:

Kevin
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Offline cudaneil

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #33 on: February 10, 2009 - 05:49:56 PM »
Darn good idea kevin !

                             Good news for me today.................got me a vacuum gauge and removed the air filter pan to connect

the gauge to the carb vacuum tube, pulled the vacuum pipe off and.............no vacuum.  The reason for that was the previous

owner had put the vac hose onto the wrong connection, the actual vac connection tube on the carb had a rubber blank on it !!!

I changed them over and the idle immediately improved.  No more stalling at idle when drive is selected.   RESULT    :bigsmile:
just one more job to do..................  (O----{|||}----O)

Offline 422STROKER

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #34 on: February 10, 2009 - 05:59:47 PM »
That was easy!

Tom :smilielol:
Tom
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Offline cudaneil

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #35 on: February 10, 2009 - 06:11:26 PM »
That was easy!

Tom :smilielol:

            If i had borrowed the vacuum gauge a week ago, it would have saved me a lot of work ! :eek4:        :grinyes:   
« Last Edit: February 10, 2009 - 06:14:05 PM by cudaneil »
just one more job to do..................  (O----{|||}----O)

Offline 422STROKER

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #36 on: February 10, 2009 - 06:17:13 PM »
You should have one in your toolbox, they cost <10 bucks.

Tom :cheers:

They are very handy for tuning your carb as well.
Tom
12.77 @ 108.87 15" Street Drag radial tires 3.23 gear

Offline cudaneil

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #37 on: February 10, 2009 - 06:22:19 PM »
You should have one in your toolbox, they cost <10 bucks.

Tom :cheers:

They are very handy for tuning your carb as well.

So how do you tune your carb using the vac gauge Tom ? 
just one more job to do..................  (O----{|||}----O)

Offline 422STROKER

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #38 on: February 10, 2009 - 06:24:50 PM »
Take a look here, if that isn't enough just do a quick search here and something should pop up.

Tom


http://www.cuda-challenger.com/cc/index.php?topic=46628.0
Tom
12.77 @ 108.87 15" Street Drag radial tires 3.23 gear

Offline cudaneil

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #39 on: February 10, 2009 - 06:45:44 PM »

 OK, read that...............................thanks Tom     :2thumbs:
just one more job to do..................  (O----{|||}----O)

Offline 340Challman

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #40 on: February 10, 2009 - 06:55:47 PM »
Great news Neil. :2thumbs: But now you're going to miss out on the dancin girls. :smilielol:

Glad you got it solved. :cheers:

Kevin
Don't look back, I might be gaining on you.
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Offline Chryco Psycho

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #41 on: February 11, 2009 - 02:24:06 AM »
ok so what you have done is removed what I assume is the vacuum advance line from the carb to the dist , there is not supposed to be vacuum on this line at idle & you have now connected the dist advance to manifold vacuum which advances the timing so now you have full advance at idle & it will decrease & retard timing with rpm so what you need to do is connect back where ti was & advace the timing at idle .Next you need to insert an allen wrench into the vacuum pot on the dist where the line connects & turn the screw approx 8 turns counterclock wise to prevent the timing from over advancing at higher RPM  :working:

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Offline cudaneil

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #42 on: February 11, 2009 - 05:20:15 AM »
  Oh no, dont tell me i havent done it right..................... :faint:

 My carb is a Holley 4160, and looking at the instructions i have, the two connections we are talking about are:

  1- timed spark vacuum source connection.

 2- full manifold vacuum source.

 The full manifold vacuum was capped off with a rubber cap........surely this should have gone to the air filter with a hose ?

  The distributor advance was connected to the timed spark source.

  I have just swapped these two around and it has solved the stalling problem at idle.

  With this information,do you still recommend what you have just said Chryco ?

                                                    thanks, Neil.

   (turning the allen srew counterclockwise INCREASES the amount of vacuum doesnt it ?) :dunno:

    Does advancing the timing give more vacuum as well ?      Im confused   :-[
« Last Edit: February 11, 2009 - 07:07:31 AM by cudaneil »
just one more job to do..................  (O----{|||}----O)

Offline Bullitt-

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #43 on: February 11, 2009 - 06:18:48 AM »
Here's a good step by step article our cub president wrote for engine timing & distributor advance.

http://tvmoparclub.com/files/tech/Mopar%20Timing.pdf

another  re: carb tune

http://www.tuningmadeeasy.com/tuning/tuning-a-carburetor-part-1/
« Last Edit: February 11, 2009 - 06:22:57 AM by Bullitt- »
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Offline Chryco Psycho

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Re: MISSFIRE ON ONE CYLINDER ?
« Reply #44 on: February 11, 2009 - 10:59:20 AM »
follow what I suggested & it will work for you Neil

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