engine backfire

Farmall Super A, AV, 100, 130, & 140 1939 - 1973

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Dusty B
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engine backfire

Postby Dusty B » Wed Jul 21, 2021 4:47 pm

Engine starts and runs fine intermittently but backfires thru the carb every little bit! seems to do it less at faster speed but still does! Timing?? carb?? fuel supply?? seems like float does stick once in a while(Gary's fault!) but once running seems to run strong!! Using old wires, but would that cause the intermittent backfire?? Glad to just hear it run!! :tractor:
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Re: engine backfire

Postby Barnyard » Wed Jul 21, 2021 5:04 pm

Timing may be 180 out or a plug wire crossed.
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Rick Spivey
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Re: engine backfire

Postby Rick Spivey » Wed Jul 21, 2021 5:32 pm

Could be timing, plug wires crossed, or intake valve sticking intermittently.
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Re: engine backfire

Postby SamsFarm » Wed Jul 21, 2021 9:55 pm

I had a car a long time ago, did not know it at the time, but, the camshaft got some of the lobes wore off, the result was backfiring through the carb because a few of the exhaust valves were not opening.

Might want to pull your valve cover off and look.

Maybe you have a bent push rod or something.
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Dusty B
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Re: engine backfire

Postby Dusty B » Tue Jul 27, 2021 8:01 pm

Barnyard wrote:Timing may be 180 out or a plug wire crossed.

Would it run smoothly for a minute or two or three without backfiring if it were 180° out?
Grandpa's '41 B
'56,,'57,'59, Cu'b
'45 C
'55 Case S
Dad's DB garden tractor
'48 DeSoto
'31 "A Coup
'79 Lincoln TC
God looks out for those of us who don't know how to look out for ourselves!

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Re: engine backfire

Postby tst » Tue Jul 27, 2021 8:24 pm

its not 180 out it would not run, check valve adjustment, timing, compression, spark plug and wires

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Re: engine backfire

Postby Eugene » Tue Jul 27, 2021 10:18 pm

tst wrote:its not 180 out it would not run, check valve adjustment, timing, compression, spark plug and wires
And/or sticking valve(s).
I have an excuse. CRS.

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Tractors Owned: 1968 Cub Fast Hitch
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Fast Hitch CS Bell 60 Grain Mill
Home Made Fast Hitch Potato Plow
54A Blade

Couple 1948 Cubs
172 Runner Planter
53 Fertilizer
Cub-3 Field Cultivator
Cub-189 Two Way Plow
Cub-22 Sickle Bar Mower
Mechanical Transplanter with side mount barrel (needs a fast hitch adapter) :)

Misc Belly Mowers

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International 100 Fast Hitch Blade
Mott Fast Hitch Flail Mower

Wish Wish Wish List
Fast Hitch Rotary Hoe
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Re: engine backfire

Postby SamsFarm » Wed Jul 28, 2021 10:48 pm

Give it a break, it is kinda old and might burp and fart a little more than usual! :lol:
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