crank pulley runout/wobble

[tekdeus]

I was under my car today while it was running, and I could see some runout/wobble in the rotating crank pulley, not sure, maybe 1mm? This engine in the past has had the bolt come loose and damage the key way. I checked it today and it was again needing to be retightend (wasn't loose enough to cause problems yet).

I've been revving it to 6000+ rpm with the new turbo. Recently the front main seal has starting to leak a bit. Any tips on what to do here?

 

[CyFi6]

Doesnt sound good, when that happens it usualy fubars the crank and the pulley beyond repair. I have a junk crank here that the same thing happened to, the snout where the pulley fits on is .015" smaller than what it used to be, and the keyway is screwed up. Not only that, but the pulley bolt threads in the crank itself are very stretched out/loose. When i screw the pulley bolt in slightly i can wobble it all over the place, i cant imagine that it would be able to hold torque

 

[Zumtizzle]

Time to find a new crank.

 

[gaboonviper85]

you dont need a new crank....pull the pulley off and see if it damaged it...if i did you can have it built back up with some weld and re ground....then have a new key cut....its not that hard!

 

[IJ.]

Crank would have to come out to do it may as well find a good condition unfucked crank to install while it's apart....

 

[Supra_Villan]

any ways of prevention of this? how common is it?

 

[IJ.]

Just make sure the Crank bolt is pulled down to 195ft/lbs and NO a fucking rattle gun isn't the tool to use....... (not directed at you SV just seems to be the tool of preference for a lot people)

 

[tekdeus]

Will that much runout damage the crank bearings? I don't have a tool to measure it, I'm just guessing by eye. I also think it has been like this for quite a while, and I only just noticed it.

 

[CyFi6]

Over a period of time im sure it could cause some damage. Its not a lot of wobble, but when you think about the rpm's youre spinning it at, it multiplies the forces. Chances are if its been wobbling before and was doing it now, the crankshaft is damaged. Its probably much cheaper to get a new crankshaft than to try to repair this one, its got to come out if its damaged anyways. Pull the balancer off and measure it/take some pictures.

 

[IJ.]

I seriously doubt it would damage the bearings but it WILL continue to destroy the fit/finish on the Crank snout and Damper bore so consider both parts junk.

 

[oldsking]

Are you running a stock crank pulley or an aftermarket one? Zumtizzle gave me a heads up on aftermarket pulleys and the counter weight system form it and how it can damage your bottom end.