Author Topic: Got a miss  (Read 9673 times)

Offline free2race

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Got a miss
« on: May 06, 2009, 11:09:11 pm »
I've done everything I know. It seems that either the motor or the carb has developed a slight backfire.  I checked the ground wire on the front of the motor, It's good. I cleaned the carb out again,changed the jets,changed the plugs and still the same thing. Anybody got something to throw at this one?




Offline justfreaky

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Re: Got a miss
« Reply #1 on: May 07, 2009, 07:00:51 am »
Have you checked your valve lash?

Steve
Better to be hated for who you are, Than to be loved for who you are not.


Offline free2race

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Re: Got a miss
« Reply #2 on: May 07, 2009, 11:43:54 am »
Not yet plan on doing a complete check tonite. I wish this thing ran a flathead.

Offline justfreaky

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Re: Got a miss
« Reply #3 on: May 07, 2009, 11:47:36 am »
I got thinking (I know, Dangerous!  :-\); Make sure you don't have a weak valve spring.
Don't know if you can access the timing, but might want to check that too if you can.

Steve
Better to be hated for who you are, Than to be loved for who you are not.

Offline free2race

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Re: Got a miss
« Reply #4 on: May 07, 2009, 12:27:43 pm »
I think I'm going to swap motors this evening. Bad thing about this is this motor has one race on it. Got a really BIG boat anchor.


Offline justfreaky

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Re: Got a miss
« Reply #5 on: May 07, 2009, 12:36:20 pm »
Does the backfire or miss seem to cause any proformance loss?
I know on my kart, that after adding the header, I now have a popping sound when letting off the throttle. I will look into jetting, but will wait 'til I get the velocity stack and filter added on. I am certain that the popping is due to excess fuel in the header.
I'm just kind of thinking out loud. I am sure the problem is not likely that serious.

Steve
Better to be hated for who you are, Than to be loved for who you are not.


Offline IraceLegends77

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Re: Got a miss
« Reply #6 on: May 07, 2009, 01:05:57 pm »
Does the car backfire when your on the gas or off? If off these cars backfire because of the exhaust systems. If on the gas I would guess that the carbs are just a little off. We need a lot more info though.

Scott #77w
Scott Wilkerson #77   Vision Graphix Racing

Offline apm motorsports

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Re: Got a miss
« Reply #7 on: May 07, 2009, 04:37:35 pm »
unplug rev limiter see if it goes away. Check to see if gasket fell  off that goes between aircleaner and carb.                Gil


Offline free2race

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Re: Got a miss
« Reply #8 on: May 07, 2009, 11:22:37 pm »
After a complete check of everything. I have decided to throw in the towel on this one. After checking and rechecking the valve lash, gaskets, ground stud, jets and (3) carbs. This thing is junkpile material. The only thing I have not done is disconnect the rev limiter. It seems when you give it gas at about 3,000 rpm it sounds like it's choking on too much fuel and it won't "lean out" and run steady. I have no clue. Thanks for the help. Maybe someone at Monroe can do something with this possible mailbox holder, I know I can't.

Offline justfreaky

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Re: Got a miss
« Reply #9 on: May 07, 2009, 11:59:26 pm »
Are you sure your jets aren't too large? Did you try to readjust your air/fuel settings?
How many races do you have on this engine? Maybe it is due for a refesher?
Sorry that I am not of more help.  :-[  It's hard to get a grip on the situation when I can not be there first hand. Don't know that I would be much help anyway.
Let us know what the outcome is.

Steve
Better to be hated for who you are, Than to be loved for who you are not.


Offline free2race

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Re: Got a miss
« Reply #10 on: May 08, 2009, 11:38:36 am »
The jets that I put in are really small compared to some of the other guys I've talked to. I think I'm going with the stock jets. I've played with the mixture and can't seem to get it to quit stumbling. I HATE THIS!!!!!

Offline free2race

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Re: Got a miss
« Reply #11 on: May 08, 2009, 08:30:03 pm »
Ok people,let me explain the outcome of the missing engine problem in a nutshell. CHECK YOUR GAP ON YOUR PLUGS. That's all i'm going to say.