5.0 harmonic balancer

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Aug 15, 2005 | 04:16 PM

gwuister

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From: Pedley

5.0 harmonic balancer

I have an '88 f150 5.0 aod. I was under the truck today greasing the front suspension and saw some rubber sticking out of the harmonic balancer. also it didn't look straight on the crankshaft. I started the engine and sure enough it is wobbling.
Question. what symptoms does this create? The truck runs pretty good, a little low on power lately. Makes some unusual noises though, almost sounds like a diesel at idle sometimes. It has 155k miles on it and I have been wanting to replace the timing chain for a while. I guess if I am going to pull the balancer I should do the chain also.
Anyone else have the balancer fail?
Thanks, Greg

Aug 15, 2005 | 05:00 PM

andym

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Joined: Mar 2002

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From: Bonita Springs FL

No, but yours definitely sounds bad. It will wear out the motor pretty quickly. It puts huge amounts of stress on the crank being off balance like that.

Aug 15, 2005 | 09:02 PM

94F150regcabMARKIII

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Joined: Jul 2003

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mine came completely separated at the beginning of the summer...it rattled horribly but i changed it out and it runs great now... good luck w/ it

Aug 15, 2005 | 10:24 PM

MRL123

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Joined: Oct 2004

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From: Wetaskiwin, Alberta

I would definitely get after that repair ASAP. If it's wobbling on the end of the crank then it is definitely, as AndyM stated, putting tremndous stress and strain on the crank, bearings and all other attached reciprocating parts. Your thoughts on changing out the timing chain are spot on. 155,000 miles is not a bad place to make the change and you are already going to be in there wrenching anyway to get the balancer off so what the H - why not. Be sure to take a really good close inspection of the water pump weep holes and make sure that the pump is OK. Since you gotta take that off to get at the timing chain - well, you probably know how that goes--------.

Also, make sure that you have all of the required gaskets to do the job. It's a real PITA when you get everything torn down and start to reassemble and then realize that you need that @#$%^ gasket for the _______ and it didn't come with the kit.

Good luck and let us know how the repair goes.

Cheers!

Mike

Aug 16, 2005 | 07:42 PM

gwuister

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From: Pedley

I ended up just replacing the balancer for now. Really easy job. All I needed to do was remove the fan belt and then the crank pully and then the center bolt on the crank. I pulled on the damper and it slid off and almost hit me on the head.
I think I really dodged the bullet on this. The keyway was 3/4" wide and cracked. The outer ring slipped out 1/2 " It could have let go anytime taking a lot with it. The crank looks good and I replaced the key.
Only thing I notice is that it idles dead smooth now.
-greg

Aug 16, 2005 | 09:30 PM

MRL123

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From: Wetaskiwin, Alberta

Well, lets remain hopeful and positive that you did in fact miss the bullet this time around - lucky SOB!! You are definitely NOT supposed to be able to just pull the balancer off of the crank without the help of a puller of some sort. Personally, I wouldn't let that timing chain matter get too far out of your mind. Stay vigilant with respect to sudden changes in the timing of the motor etc. in case the chain does jump a tooth or something along those lines.

Cheers!

Mike