302 problems?

[CrimsonGT]

A friend of mine has a 95 F150 auto with a 302 in it with a little over 100,000 miles on it. He has took it to a delarship cause his serpentine belt is getting chewed up along the inside of the belt, they told him he needed a new engine or rebuild the bottom end at least cause the crankshaft has moved forward. And he was like WTF cause his truck runs fine.

The pully attached to the harmonic balancer looks to be 1/4 inch father out from the engine block than the other pullies. I looked at the harmonic ballancer to see if it has shifted forward that looked fine, but at the seal in the timming cover I noticed a shinny ring around the cranshaft that was about 1/8 to 1/4 inch wide. Looks like a polished area where a seal has been riding.

So the question is can the crank shaft move a 1/4 inch forward and the engine still run fine? second question has anyone ever heard of this happening?

[Dale McPeters]

Did they check the harmonic balancer bolt to
make sure that it had not starting coming loose?
Crank thrust bearing wore out?

[coupe]

Yea, crank can move forward....usually goes back when not running, but if there's any load from trans/torqueconverter, it will push it forward to stay. It does sound like the thrust bearing might be an issue. :(

[CrimsonGT]

thanks
I was thinking along the lines the thrust bearing being bad but I'm not mechanically inclined so I told the guy i would ask around. Its just he doesn't have the money right now so he is looking at his options.

[One_live95]

keep replacing the belt till it tears up...... :shrug:




jason

[Blown 5.0]

We have a fleet of Ford Trucks. One in general comes to mine, although it is higher milage than your friends it to eats the inside groove off the belt. It has never given any trouble as far as throwing the belt, after it eats off the one groove its fine. Has ran many years like this.

[CrimsonGT]

We have a fleet of Ford Trucks. One in general comes to mine, although it is higher milage than your friends it to eats the inside groove off the belt. It has never given any trouble as far as throwing the belt, after it eats off the one groove its fine. Has ran many years like this.

that is what we have going on just the inside of the belt, about one groove, but never throws the belt off.

the guy is going to drive it till it falls apart, but wants us to use the machine shop at work to get the pully to stop chewing up belts.

I told him to find a belt the same length but with one less rib in it, and install it on the good half of the pully.

[CrimsonGT]

thanks guys for the info

[snakebit95]

The crank should not move 1/4". If it has moved that much, the thrust bearings are toast!! Checking the balancer bolt is a freebee, so I would start there. If you can find a long straight-edge, you could check the alignment between the other pulleys. Have you inspected all the pulleys for sharp edges or burrs? Maybe a damaged pulley groove could be eating on the belt? Just some other ideas that come to mind. I always check the free stuff first.

[CrimsonGT]

the pullry on the harmonic balancer is noticable out of alignment with the rest of the pullies