knocking engine

k-man

New Member
Jul 27, 2009
7
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spokane, wa
i just got a 95 gt, had a bad vibration at idle and found that the harmonic balancer had come apart, so changed it out with one off parts engine and now runs smooth.. and yes it is 50oz had same part number as old one..
but now that all is fixed the car has a rod knock, guess the guy ran it long time messed up.
so anyone know if i yank the engine and just replace the rod bearings if that would be all i need or replace the mains also? :shrug:
 
Wont really know till you tear it apart. Funny thing is, i went thru the exact same progression somewhat. Noticed the balancer wobbling a bit, replaced it, motor started knockin, piston broke off rod and engine went BOOM lol. Tear it apart and see!
Matt
 
i just got a 95 gt, had a bad vibration at idle and found that the harmonic balancer had come apart, so changed it out with one off parts engine and now runs smooth.. and yes it is 50oz had same part number as old one..
but now that all is fixed the car has a rod knock, guess the guy ran it long time messed up.
so anyone know if i yank the engine and just replace the rod bearings if that would be all i need or replace the mains also? :shrug:

I think it's more than likely the main bearings will be shot. Just cross your fingers and hope that the crank journals won't need to be reground.
 
Hopefully if, as soon as you noticed the knocking, you parked the car, the damage won't be too bad... A friend of mine with an N/A 300zx chipped his car and it brought the rev limit to 7,800, even though his cams ran out of juice by like 5-6 grand... He constantly revved it that high, and ended up getting a knock about a month ago. Instantly shut the car off, towed it to his shop, we tore into it and just found a single spun rod bearing. The rest of the rotating assembly looked just fine, so I hope you have the same luck!

On the bright side, if the internals are unfortunately shot, 351 swap? :nice:
 
thanks for the advice everyone! i did park the car right after replacing the balancer right when i noticed the knock.... well and for the fact that the same night the auto trans in it decided to only work in 1st and 2nd gear :notnice:

going to yank the engine-trans, replace the mains and rods. i got a crank from my friends engine that he put a 331 stroker kit in.. same engine that the balencer came off of.

does anyone around the washington-idaho area have the parts needed to convert to manual trans??