I've noticed some significant wear on my fan drive belt recently ('79 MCI5C, 6V92) and I'm wondering how to change it out. Attached are pics of what I *think* is a belt tensioner that allows me to loosen, remove and replace the belt. Am I barkin' up the right tree here? How does that mechanism work? Thanks, as always, for your knowledgeable assistance!
-Chuck
Yes, that is the tensioning mechanism. Follow the airline on the ram to its shut-off valve.
If you are lucky, it will power in the opposite direction, if there's air pressure.
If not, you have to pull down on the belt.
Hang the top first, hang on it, and slip the bottom on.
Keep the old one as a known good spare.
Happy coaching!
Buswarrior
Buswarrior- thanks for the help! I'll work on it this week and get back to you if I run into stags.
-Chuck
Ok, finally got around to messin' with this today. Yes, the tension mechanism does relax when I release the air pressure. Two questions:
-There is still considerable tension present and it requires two hands and my body weight to pull it down, which leaves me with no hands to slip the belt off. Is this simply a two person job? Or a clever bit of placement of a pry bar?
-The attached photo is looking down at the main drive pulley. As you see, there doesn't appear to be enough room between the pulley and rear bumper to either slip the old belt off or the new one on. This is a 6V92 occupying the space of the original 6V71 so I'm guessing the close tolerances are related to that. But how do I get the belt through a space that's about 50% too narrow?! Do I have to remove (or significantly loosen) the rear bumper to do this?
Ps. It's normal for the engine to sit slightly off of square with the coach body, right?
You could disconnect the linkage at the tensionner. Or use a pry bar with one hand while the other slips the belt off the upper pulley. And yes, you might have to loosen the bumper to get the necessary clearance.
Oh yes, the engine sits at an angle because the drive shaft goes over and to the side of the differencial to connect to the drop box.
Thanks, JC. I'll check out the bumper removal/loosening... maybe it's not that big of a deal.
Chuck
The bumper is held on by one bolt on each side. Remove the nut from inside the engine compartment. Then there is the inner bumper/brace. It is held on by 1/2" bolts (5 each side on my bus). 3/4" wrench. 10 minute project.