new user / carb problems
Thread Starter
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Freshman User
Joined: Aug 2002
Posts: 31
Likes: 0
From: Ktn USA
new user / carb problems
Hi all, I am am the new owner of a 73 F100. I really love it (even with all its things in need of fixin!) One big problem though, I have a 360 with a holley 4bbl on top (stock?? I don't know) Problem is, when I let off the gas or down shift, it starts backfiring like crazy. My guess was the carb is running too much fuel, so I backed off the fuel to the point of making it stave, but it still backfires. Could the carb itself need replacing??
Thanks
Casey
Thanks
Casey
Cargo Master
Joined: Jul 2000
Posts: 2,281
Likes: 18
From: Northern California
new user / carb problems
Welcome to FTE!
>Hi all, I am am the new owner of a 73 F100. I really love
>it (even with all its things in need of fixin!) One big
>problem though, I have a 360 with a holley 4bbl on top
>(stock?? I don't know)
I don't think any of the 360 trucks came stock with a 4v carb, it's probably a conversion someone did.
>Problem is, when I let off the gas or down shift, it starts >backfiring like crazy. My guess
>was the carb is running too much fuel, so I backed off the
>fuel to the point of making it stave, but it still
>backfires. Could the carb itself need replacing??
I'd do a rebuild of the carb, if it's backfiring out the carb then it's too lean, backfire out the exhaust is too rich.
Since you just got it, I'd do a complete tune up and check the timming. The carb kit should only be about $20.
>Hi all, I am am the new owner of a 73 F100. I really love
>it (even with all its things in need of fixin!) One big
>problem though, I have a 360 with a holley 4bbl on top
>(stock?? I don't know)
I don't think any of the 360 trucks came stock with a 4v carb, it's probably a conversion someone did.
>Problem is, when I let off the gas or down shift, it starts >backfiring like crazy. My guess
>was the carb is running too much fuel, so I backed off the
>fuel to the point of making it stave, but it still
>backfires. Could the carb itself need replacing??
I'd do a rebuild of the carb, if it's backfiring out the carb then it's too lean, backfire out the exhaust is too rich.
Since you just got it, I'd do a complete tune up and check the timming. The carb kit should only be about $20.
Thread Starter
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Freshman User
Joined: Aug 2002
Posts: 31
Likes: 0
From: Ktn USA
new user / carb problems
yea, I was planning on going that route anyway, just wondering if there was some easy fix (there never is though is there??) Anyway, off to NAPA to load up on tune up material...
THanks
Casey
THanks
Casey
Elder User
Joined: Jul 2002
Posts: 526
Likes: 0
From: USA
new user / carb problems
have you checked for any exhaust leaks? min has a small leak at the collector and will bark a little bit if i gun it then let off the gas. also make sure you check the vacuum advance, it seemed to help with that problem on mine.
1977 F250 460
C6 Hedman Headers
Dual 40 series
edelbrock performer
holley 4160
msd 6a and blaster coil
1977 F250 460
C6 Hedman Headers
Dual 40 series
edelbrock performer
holley 4160
msd 6a and blaster coil
Thread Starter
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Freshman User
Joined: Aug 2002
Posts: 31
Likes: 0
From: Ktn USA
new user / carb problems
I did look, but I have a brand new straight pipe setup, it doesn't have mufflers or glass packs though, just straight pipe and a couple tips. I am sorta wondering if having very little back pressure could be a cause of the backfire?? I am getting a muffler to put on there, just need to find one that will fit...
Thanks
Casey
Thanks
Casey
