ok...I have got an engine vibration. I didnt have it before I changed over to the manual tranny. I have several 302's floating around the garage and thought I might have but the wrong harmonic on it...so I pulled it off monday to check the date code...and of course the first year letter was missing via a hole. I grabbed another one that was date coded "C5" which was heaver than the one I took off...fired up the the engine and still had the vibration...next I though ok maybe a bad miss, so I got the IR temp gun out and measured the tubes....all 400+ except cyl #3 150 degrees...removed the plug and the gap was closed...fixed that and it still has a vibration...checked the flywheel and it has a date code of "D8"...The engine has a date code of "C8" so it looks like everything is a 28oz imbalance. what is strange It doesn't fill bad on the outside but when I am behind the wheel it vibrates the wheel like crazy......any suggestions. Robert
Could be the input shaft or pilot bearing. What transmission are you using? Do you have the correct balance flywheel?
i would have the flywheel checked. does it make a difference if the clutch is engaged or not? they can get hot and warp like a rotor
if all you changed was the fly wheel and trans then the problem has to be there. the balancer that was on that motor originally should be put back on. the flywheel would be my first suspect. my machine shop told me that they can match the balance of the old flex plate if i replace it with a different one or a fly wheel. i would recomend having that done. next i would suspect the clutch pressure plate may not be balanced. im not sure how you would check that becides changing it. does it shake just based on engine rpm, or does the clutch have to be released and you driving down the road to feel the vibration?
The flywheel and bell housing came off the 73 6cyl comet I parted out this summer. It doesn't change at all when I press in on the clutch. I don't feel any added vibration through the pedel. when I grab the shifter I can feel the vibration through it. The engine came as is. it already had the 4bbl stuff and a nice rumble of a cam and the automatic floor shift. it didnt have a vibration before the 4-speed swap. I tinkered with it some more last night and the vibration is very noticeable inside the car, when standing beside it with your hand on the breather it isn't. I started wondering if maybe it is the new exaust I had put on last week. Robert
I found online that a 221-351 up to 1981 was the same and was 28oz. I have another flywheel in the garage that I could change out but it needs to be turned..has been heated and has surface cracks. Robert
You are half right and the half my be my problem.....221-250 6cyl are 28oz but the 300 6cyl is zero balance....the comet I got my parts from was swapped from a 302 to a 6cyl which me and chuck figured it was a 300 because it looked bigger that a 250...... Robert
Here is a quote from the 6 cyl performance handbook. I don't know much about big 6 except it a lot bigger and looks different with a removable intake. Here is what the back side of a SBF flywheel
I am in the garage now taking it all apart to install a C5 coded flywheel. I have the camera up and going. http://robertbailey.homeip.net:8081 Username = mcci password = mcci I will shut it down later tonight. Robert
ok...she is fixed.got it all back together and went around the block and no vibration. either the flywheel stuff online about the 6cyl is correct or my first thought was correct and the motor from the comet was a 300 6cyl...which chuck thought too. anyhoo she is fixed and drivable now to do some test driving during the daylight. Robert
