7mge Massive vibration issue! Please Help!!!

[MKIII The Supra King]

Hello i just bought my 88na roughly 6 months ago, all in all an awesome freakin car i love it, little sluggish but operates normally (for the most part). Until one day i slammed it coming around a corner punched it in first then went for second after i got around, and for a split second, felt something very odd and since then i have a wicked vibration that becomes unbearable around 4000 rpm, but no misfire and no noise. it happens in neutral and in gear at any speed. i just did a bunch of overhaul after the vibration came in. replaced motor mounts trans mount, re sealed trans, rear main seals, control arm bushings, ball joints upper and lower, valve cover gaskets, plugs and wires, and im at the point where im just gonna hop in it and ride off a cliff cause i sure as hell aint sellin it. any insight would be greatly appreciated!!!!

[interested!]

Originally Posted by MKIII The Supra King

Hello i just bought my 88na roughly 6 months ago, all in all an awesome freakin car i love it, little sluggish but operates normally (for the most part). Until one day i slammed it coming around a corner punched it in first then went for second after i got around, and for a split second, felt something very odd and since then i have a wicked vibration that becomes unbearable around 4000 rpm, but no misfire and no noise. it happens in neutral and in gear at any speed. i just did a bunch of overhaul after the vibration came in. replaced motor mounts trans mount, re sealed trans, rear main seals, control arm bushings, ball joints upper and lower, valve cover gaskets, plugs and wires, and im at the point where im just gonna hop in it and ride off a cliff cause i sure as hell aint sellin it. any insight would be greatly appreciated!!!!

Hi ! , Have you checked out the harmonic balancer ? , this has a habit of coming loose on the crankshaft . To check , release the tension on all the belts and see if it wobbles . If it does then that could be your problem .
It is repairable by sleeving or replacing the crankshaft and balancer.

[MKIII The Supra King]

Huh I did notice that i cracked two balancers, I replaced the first one then it cracked again I was wondering if it was a crank issue as well. Good to know I wasn't going crazy. Thanks alot your the first person I've found thats had any information on the matter. Now its time for me to get back to the grind and start tearing it apart. I cant wait for my baby to be running again. Thanks again!!!!

[interested!]

Originally Posted by MKIII The Supra King

Huh I did notice that i cracked two balancers, I replaced the first one then it cracked again I was wondering if it was a crank issue as well. Good to know I wasn't going crazy. Thanks alot your the first person I've found thats had any information on the matter. Now its time for me to get back to the grind and start tearing it apart. I cant wait for my baby to be running again. Thanks again!!!!

Hi again ,
If your pulley is loose --the crankshaft has probably worn -( this has damaged the woodruff key and slot) - towards a cone shape and the pulley has probably worn to a cone in the opposite direction . this can be repaired by gaining access to the crankshaft with the timing belt and crank gear removed and stepping the crankshaft to PARALLEL to its now smallest diameter up to the gear position using a machined tube with a spigot to maintain a parallel repair --fit/mark/file--fit/mark/file etc ,repairing the slot with a two part metal epoxy paste and fitting a sleeve in a machined pulley with a slot for a new key. finally after all slides nicely together in the correct position,drill a hole through the pulley/sleeve/crankshaft and fit a bolt ( head and thread removed )to prevent rotation on the crank --removing strain on the woodruff key.it worked for me 10 years ago and came apart easily 8 years later for a new timing belt. fit a new crank seal and a new timing belt etc for a long life. Also check that the TDC mark on the pulley is ACTUALLY the TDC point of the piston , mine was 2 degrees out ! . ( checked it with a dial test indicator on top of the piston ) . This repair took me a week . The hardest part was filing down the crankshaft as it was worn by approx. 5 thou. The spigot on my tube was longer at the start of filing the crank and was cut down as I worked nearer to the timing gear . The spigot diameter is EXACTLY the inner diameter of the crankshaft bolt thread , this centres the tube for filing . The tube inner diameter is the diameter that my crank had worn to and was the diameter I had to file the crank to parallel. Your tube will have to be purpose made . I had my car on ramps to carry out the repair . Remove the radiators for access . The flywheel was restrained with a metal strap attached to the gearbox bell housing for torqueing the pulley bolt . ( mine was an automatic ) .