hey all, i have a 360 in my '73 with factory A/C. I noticed the other day that the belt wasn't riding in the groove of the idler pulley (i think that's what it is). I've tried tightening the belt as much as i can, but once i start the engine, it still jumps out. no clue how long it's been like this, since the truck has been running fine. for the time being, i just took the belt off. but is there any way to get everything back in line? it clearly comes off the crank pulley and has to bend some to get in the idler groove before it passes around the a/c pulley. i do think the idler pulley thing is in need of replacing as it doesn't spin well and there is an annoying noise that happens when i click on the a/c that i feel might be that pulley.


these pics don't really show it well. the belt is actually riding on the outer lip of the pulley. the pics make it look as if the belt is not even touching the pulley, but it is. the outer edge....

 

Time to get the ol' wrenches dirty and replace that worn out pully bearing.

 

for some reason, i can't seem to find that part in my LMC catalog.

 

I'll look through my junk this week, see if I can get a bearing number to cross reference. Looking at the pictures, I'm not sure you have that much to take to the auto parts or industrial supply.

 

D8OZ8678A .. Idler Pulley Assy-Adjustable Type (Motorcraft YS103) / Obsolete

Even though my ref says this is obsolete, I believe it's been replaced by another part number and is still available from Ford. Will find out later today, post the info.

(D8OZ8678A replaced DOAZ8678C & C8AZ8678A)

Fits: 1968/76 F100/350 360/390 / 1969/79 F100/350 302 / 1973/79 F100/350 460 / 1977/82 F100/350 351M/400 / 1980/89 F100/350 255/302/351W.

Fits: 1975/91 Econoline 302/351M/351W/400/460.

Fits: 1968/79 most passenger cars with: 302/351C/351W/390/400/428/429/460 engines.

Originally sold by Ford as a one piece assembly.

Dunno if you can just buy the pulley (comes with bearing) by itself from an autoparts store.

I know NAPA sold the assembly at one time, prolly still does...considering everything it fits.

 

I replaced mine with bearing from local supply house. OD, ID and width is all you need. Take it with you and guy at counter will likely help.

 

Or, see if you can find numbers on the bearing itself.

 

This part IS obsolete...no longer available from Ford.

 

forgive me for being naive, but does the pulley come off easily? as far as i can tell, it's two bolts. they're caked up good with grease and dirt, which is why i can't see it perfectly.

 

It should. Mine was held by a single bolt thru the pulley. You might have to take the bracket off then remove the pulley from the bracket. My '67 was up top, so it was in plain sight.

 

update --- tried to remove the pulley today, but no luck with my limited tools/skills. took it to the local garage and his first reaction was that it was the A/C compressor out of alignment. I can understand his logic because the crank pulley and the idler pulley all line up perfectly, but the A/C pulley is set back a bit. He doesn't really know what to do, but said he'll work on it and see if he can figure anything out. Kind of odd, me thinks.

 

Well what my dad taught me was to stand on one side of the truck and look at your belts when its not running to make sure they run true if not he would use some 3/8 washers to shim it up until the belt ran true and straight and didn't throw the belt. Time consuming to get your belts shimmed just right but to me worth the extra time and effort. Might be cosmetically harsh for some but throwning a belt on the freeway and losing your water pump and steering is not alot of fun (did this). Some of the alternators also have shims that will work if its really far out of whack. Backyard mechanic stuff i know but aren't all of us to some degree LOL. Anyways just my .02

 

update -- the mechanic at the local garage went ahead and just took the pulley off. he said that it wasn't really necessary for the operation of the truck or a/c. in all honesty, i kinda have to agree. without the pulley there, there is no difference whatsoever. the tensioner pulley is still there, everything runs straight and true.