408 Stroker crank pulley wobble

airobats · #1 (**permalink**) 10-31-2013, 01:43 PM

I have a FFR Cobra kit car with a 408 stroker motor in it. Let me start off by saying I know very little about this car as it was recently willed to me by my late father. He had been having an issue of an oil leak from the front of the engine and when I fired it up I noticed the crank pulley (harmonic balancer) wobbling. I know a few things about engines so I immediately shut it down to avoid damage but I question how long he was driving it like this and if it could have damaged the crank, thus causing the failure of the front crank seal. Also, can anyone suggest the best place to purchase a new harmonic balancer and crank seal? Thanks.

bobcowan · #2 (**permalink**) 10-31-2013, 02:08 PM

The first thing to do is pull the balancer off and see what you've got.

After you remove the bolt, stick your finger in there and feel the end of the crank snout. The end of the crank snout should be below the level of the balancer hub. If it is not, then that is the reason for the failure.

madmaxx · #3 (**permalink**) 10-31-2013, 06:08 PM

Get a dial indicator and check crank end play. Should be .004 to .008 ". If within range and I am 99% sure it is then replace balancer. Very easy to replace front seal once balacer is off.

Tim Brewer · #4 (**permalink**) 10-31-2013, 06:46 PM

If you do need a balancer, order one online from either Jegs.com or Summit.com.

sllib · #5 (**permalink**) 11-01-2013, 07:24 AM

Before you get too far into this, make sure it's the balancer and not the pulley that's wobbling. I had a similar problem with mine and it turned out to be a March pulley that made it appear that the balancer was bad. The cure? I took the pulley off and moved it 90 degrees and remounted it. No more wobble.
Bill