i have a old ford pickup with a 351 cleveland in it(NOT ORIGINAL MOTOR) i recently got dual exhaust put on it and when i get up to around 55 mph i hear loud backfiring out of the pipes.its a fast pop and happens a couple times a second.also a moth or so back it broke a lifter bridge on the drivers side of the motor.i replaced all lifters and push rods.i hear a slight tapping on the drivers side motor.can you think of anything that it possibly might be and what i could do to fix it. also it doesnt smoke,but everynow and then it does pope out of the carb example going up a hill or passing a car. i thought that might be timing but it didnt help when i adjusted it.
2007-03-15 06:32:03 · 7 answers · asked by josh_ford_289 1 in Cars & Transportation ➔ Car Makes ➔ Ford
i did a compression test i forgot the compression numbers but wasnt to bad one cylinder was a lil lower than others but still passed
2007-03-15 06:48:07 · update #1
You've got a valve sticking. did you replace the valve guides and have the heads machined when you replaced the valves, or did you just tear it apart slap new valves in and call it good? Also new Valve springs would be a great idea, looks like its time to tear the top end off the motor again--unfortunately.
2007-03-15 09:57:08 · answer #1 · answered by Keith C 5 · 0⤊ 0⤋
You have backfiring, caused by unburned gas ingniting during the exhaust stroke of your engine. Timing at the distributer could be set right, but maybe your timing chain or belt is worn or slipping.
You should also check your spark plugs, wires and distributer. Water in the gas or a lean gas mixture can also cause backfiring, so you will want to check your fuel, clean your carb and fuel filter.
2007-03-15 13:56:00 · answer #2 · answered by Doug G 5 · 0⤊ 0⤋
Poissibly a bent valve, bad valve spring, flat spot on the cam or a bad lifter.
2007-03-15 15:56:43 · answer #3 · answered by Bob J 2 · 0⤊ 0⤋
Could be a tight rocker arm adjustment, Bad valve,flat cam ,weak valve spring.
2007-03-15 14:20:41 · answer #4 · answered by (A) 7 · 0⤊ 0⤋
You have a bent or burned valve. Do a compression test to verify my diagnosis.
2007-03-15 13:39:44 · answer #5 · answered by yes_its_me 7 · 0⤊ 0⤋
I agree sounds like a bent valve,are your springs good?
2007-03-15 13:54:16 · answer #6 · answered by Johnny 4 · 0⤊ 0⤋
Pull your spark plugs and see how they look. Sounds like it is running too lean.
2007-03-17 21:47:04 · answer #7 · answered by Anonymous · 0⤊ 0⤋