Mite runs really bad

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Bill H.
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Mite runs really bad

Post by Bill H. » Sun Sep 03, 2017 8:44 pm

Okay, my Mite has been sitting for some time and when we moved I almost couldn't get it started to pull up on the trailer. We were at sea level and hav e now moved to 4300 feet above. Same story taking it off the trailer. Barely got it started and had to keep my foot in it just to back it off the trailer into the shop. Fast forward a week, I went out and it started right up and ran like a charm. Idled great, revved great. It ran for probably 10 minutes perfect. I started clearing out the back of it and it started sputtering. I figured it was low on or out of gas so I shut it off. I put five gallons of gas in it and now I get the same as before; it will start but it runs horrible, won't idle and won't rev. It also is backfiring through the carburetor.

I pulled the distributor cap and cleaned all the contacts and shot some WD40 in the cap. Still the same thing. So I pulled the carburetor and pulled it apart and blew carburetor cleaner and air through all the ports and jets. Still the same thing. Any ideas??? TIA
Bill H.

Welfare, a modern day career choice.

1962 AMC M422A1
1965 Stevens M416B1

2 Timothy 3:1-5

hambone
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Re: Mite runs really bad

Post by hambone » Mon Sep 04, 2017 7:51 am

Sounds like it could be the coil??? Hambone

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Bill H.
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Re: Mite runs really bad

Post by Bill H. » Mon Sep 04, 2017 9:39 am

I thought about that. I put a brand new one in it about two years ago (a genuine NOS, not foreign) and it hasn't been driven much since. Means nothing I know but darn it! Thanks for the reply and I'll check it.
Bill H.

Welfare, a modern day career choice.

1962 AMC M422A1
1965 Stevens M416B1

2 Timothy 3:1-5

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Bill H.
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Re: Mite runs really bad

Post by Bill H. » Tue Sep 05, 2017 12:19 pm

I got it running perfect. I have no idea what it was exactly because I pulled the point plate and coil out of the distributor and cleaned everything and oiled the advance weights then put it all back together and it ran great. It must have been a back connection on something in the ignition system of the distributor.
Bill H.

Welfare, a modern day career choice.

1962 AMC M422A1
1965 Stevens M416B1

2 Timothy 3:1-5

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Bill H.
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Re: Mite runs really bad

Post by Bill H. » Mon Sep 11, 2017 8:53 am

The wife and I went for a short 20 mile cruise through the mountains the other day. The Mite ran unbelievably good. We were returning and were less than two blocks from home and it started that same horrible running with back fires and no acceleration at all. We towed it home and I pulled the distributor cap checked all the connections but otherwise found nothing at all. Again, I sprayed some WD40 into the workings of the distributor. I put it all back together and it fired right up and ran perfect. I put close to 20 more miles on it with no issues. I am beginning to think maybe the condenser or coil may be breaking down under heat??? As stated in an earlier post, the coil is a USGI NOS pulled from a an M151 distributor.
Bill H.

Welfare, a modern day career choice.

1962 AMC M422A1
1965 Stevens M416B1

2 Timothy 3:1-5


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Re: Mite runs really bad

Post by hotrodjoe » Mon Sep 11, 2017 10:18 am

do you have a fuel filter before the carb I once had pretty much the same issue and found it foreign material in the tank once cleaned and put back in I put a fuel filter just before the carb :D

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Re: Mite runs really bad

Post by hambone » Mon Sep 11, 2017 11:10 am

I started to ask how long you ran it after you got it back going, sounds like a typical coil failure, runs well until it gets hot and then malfunctions, remember, the NOS coil you put in it is still 40 yrs old and the shiny Chinese coils don't hold up. If you can get your hand on another NOS, that's what I would do, I'm running 40 yr old coils.

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Re: Mite runs really bad

Post by Ben Dover » Mon Sep 11, 2017 5:01 pm

Check to see if either of the two small Primary wires are pinched or chafed where they go over the top edge of the coil. This is a common fault with those wires. They get caught between the cap and edge of the coil if one is not careful. I can provide a NOS TO Primary wire w/condenser attached that goes to #12 Circuit.
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Bill H.
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Re: Mite runs really bad

Post by Bill H. » Wed Sep 13, 2017 8:58 am

Thanks guys. All the wiring is in great shape. It has been running now for a few miles now and no issues.

I do not have a fuel filter other that the one in the tank. It backfiring suggests ignition electrontics. I get the feeling that it's either the coil or condenser breakinget down.
Bill H.

Welfare, a modern day career choice.

1962 AMC M422A1
1965 Stevens M416B1

2 Timothy 3:1-5

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