engine vibration March 09, 2007, 09:19:29 AM i got a 89 3.8 from a friend and swapped it into an 88 cougar Lx,the 89 had the harmonic balancer missing so i put the balancer from the 88 on it and upon acceleration it shimmies/vibrates.when i put it in park and hold it at a steady rpm it has a vibration. is there a difference between the 88 and 89 balancers/is the 89 3.8s internaly balanced?has new plugs,cap,rotor and wires.any suggestions would be appreciated. Mike:cougarsmily: Quote Selected
engine vibration Reply #1 – March 09, 2007, 10:05:23 AM I don't know if there's a difference.Are the motor mounts in good shape.I had a shimmy problem with my old (long gone) 3.8,and the rubber insulator on the driver side motor mount was vapor.The mount fixed my problem. Quote Selected
engine vibration Reply #2 – March 09, 2007, 10:08:22 AM motor mounts are new,replaced with engine.both mounts on the old engine were trashed,i have a 5.0 from a markII but decided to keep it for a future project. Quote Selected
engine vibration Reply #3 – March 09, 2007, 11:16:42 AM The 1989 3.8 did not have a balance shaft...only the 1988 did, under EEC-IV. If you're installing a 1989 motor you should not have to install the balance shaft. There may be other issues (dampener, flexplate, converter, driveshaft) that are being affected by it being in there. I would suggest removing the balance shaft and seeing if the vibration goes away. That's about the only thing you can do at this point. Quote Selected
engine vibration Reply #4 – March 09, 2007, 11:39:10 PM just got home from work,thanks for the replies.i took the engine out of an 89 so i assumed it was an 89 engine,before i installed it i put new gaskets on and it had the balance shaft already in it,may be ill just sell it and start saving for the next project.thanks Quote Selected
Topic: engine vibration (Read 695 times)
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