I've searched the forums fairly extensively and found lots of problems and when they are solved the person usually doesn't report back as to its outcome. I don't want to re-hash a subject, but I don't seem to find a solution to my issue. Here are the details: 1974 Maverick 250 I6 35,000 original miles I just bought the car a few months ago and found a unique engine vibration in at at 2500-3000 rpm. In haste, I ordered a rebuilt long block and swapped out engines. Same issue. The only parts that are swapped from the original engine is: 3 groove harmonic balancer Transmission (I replaced everything else, including new flexplate. The mounts are original. The transmission is incredibly clean and works well. Balancer looks new and has very little wear.) The vibration is a rhythmic vibration that peaks in the 2500-3000 rpm range. Would this be something in the balancer or possibly the mounts? Torque converter? I will be more than happy to work with your suggestions and post the results.
Is the vibration when you rev it up to those rpms or is it when your driveing at those rpms? What accessorys does your motor have? Try removing the Belts, rev it to where the vibration occures. Is it still there or is it gone? dont run it with out the belts for more than 1 to 2 min. It could the the torque converter also.
Vibration occurs at revs and driving rpms alike. Did as suggested: Removed all belts and ran for 1 minute. Outcome: Vibration is still present. Since the car sat for 10+ years. Would torque converter be a possible culprit or even be likely?
that all that is left. maybe a weight fell off it or all that siting allowe enought setiment to form on what was the lowest point druing the 10 years of siting. that would creat a imbalance. at this point i would have the converter set out for cleaning or replace it.
The only other component you re-used was the harmonic balancer?? Personally I would have replaced that as well,slipped balancer will cause the vibes too. I would check crank endplay on the new engine as well too much thrust bearing clearance will make the crank walk and cause your vibe as well. Just becuase its a re-man dont mean the thrust is correct.Good luck.
This is a new motor with the same engine vibration as the last motor. Which, when you put everything into question, the only thing that is common with the two motors is the harmonic balancer, transmission, and mounts. One of those has to be suspect, but which one is more likely. It's no fun replacing part after part trying to find the culprit.
On the docket is: Remove and replace torque converter Replace transmission mount Replace harmonic balancer I will have results posted by tuesday.
borris i think your headed in the right diretion bryant is right about the torqe converter after sitting so long or a weight fell off keep us posted
When you replaced the flex-plate , you did get one for a 250 six cylinder, right? The V-8 plate will bolt on but it has a counter-balance weight and the six's don't use one. Same with the balancer.
he has the same vibration as before. the converter or the balancer are all that can really be causing it. i dont know if there is a balancer that will fit that motor that could be have the wrong imbalance. sence he says that it looks new, it could be the wrong one. the balancer is alot easyer to change than the converter so it might be a good idea to change that first but i really suspect the converter to be the problem
Converters are zero balance. None of them are used as engine counterweights. New ones can sit around for years on the shelf - what would make it go out of balance? If he bought a flex-plate for a 302 instead of the 250 he would have an out of balance issue. If the old one was out of a 302 he would have the same out of balance as before. If the balancer/pulleys are one piece then they are for his 250. The V-8 balancers have bolt on pulleys but the sixs are integral.
On my car, I had a Vib. Changed the balancer. Changed the trans mount. Found a broken motor mount, changed both of them. Still had the vibe. Trans was working fine until it blew up. it turns out the input shaft had a bushing that was completely toast causing the vib and the breakage of the motor mt and trans mount. Had the trans re-built ans no vibe at all now
Verified that the flexplate and balancer was indeed for a 250. My suspicion is the transmission as well. They are "reasonable" for a rebuilt one, maybe I should go that route.
