351M running rough...need help!
Thread Starter
|
Junior User
Joined: May 2002
Posts: 56
Likes: 0
351M running rough...need help!
Okay, I have a '77 351M That is running like crap lately. I think it is in the carburetor, but here are the symptoms.
Won't rev up fast (poor throttle response), it hesitates if you give it wide open throttle, and often backfires through the carb if you floor it from an idle. It even backfires out the tailpipe at times. Under constant acceleration it often feels like it is missing. I have played with the timing trying to work it out, but that doesn't seem to help. Currently it is timed at 12 degrees btdc like the valve cover says. It has the stock Motocraft 2 bbl and mated to a NP435 manual trans.
All your help is apprciated, just point me in the right direction! Thanks, Josh
Won't rev up fast (poor throttle response), it hesitates if you give it wide open throttle, and often backfires through the carb if you floor it from an idle. It even backfires out the tailpipe at times. Under constant acceleration it often feels like it is missing. I have played with the timing trying to work it out, but that doesn't seem to help. Currently it is timed at 12 degrees btdc like the valve cover says. It has the stock Motocraft 2 bbl and mated to a NP435 manual trans.
All your help is apprciated, just point me in the right direction! Thanks, Josh
Posting Guru
Joined: Jun 2002
Posts: 1,099
Likes: 0
351M running rough...need help!
It could anything.
Incorrect timing, weak spark, bad plugs, worn dist. shaft, vacuum leak, carb, worn cam lobe, bent pushrod, stuck or broken valves, valve spings, piston or ring damage, crappy gas, should I keep going?
It's hard to solve problems long distance.
Fill us in on everything you have positively checked.
Incorrect timing, weak spark, bad plugs, worn dist. shaft, vacuum leak, carb, worn cam lobe, bent pushrod, stuck or broken valves, valve spings, piston or ring damage, crappy gas, should I keep going?
It's hard to solve problems long distance.
Fill us in on everything you have positively checked.
Thread
Thread Starter
Forum
Replies
Last Post
10129
1973 - 1979 F-100 & Larger F-Series Trucks
4
Feb 9, 2015 03:39 AM
evam350
Big Block V8 - 385 Series (6.1/370, 7.0/429, 7.5/460)
12
May 26, 2012 04:52 AM
