Alternator Belt

[Guest]

My A&P and I are considering changing the crank seal. Reading about it, it says most places to change the alternator belt while the prop is off since, well, it’s off. There are a couple of options for my Io 360 on my 76 M20J.  Is there a good way to know which one so I can order it ahead of time before we decide to pull it apart?

[LANCECASPER]

40 minutes ago, Kerrville said:

My A&P and I are considering changing the crank seal. Reading about it, it says most places to change the alternator belt while the prop is off since, well, it’s off. There are a couple of options for my Io 360 on my 76 M20J.  Is there a good way to know which one so I can order it ahead of time before we decide to pull it apart?

See if you can read the part number on the existing belt on the airplane.

[Falcon Man]

The alternator belt on my 1986 K model is cracking. That part number is not available any more. Alternatives?

[Guest]

It’s based on size, so we can measure it. There are two options based on width. 

[Falcon Man]

Kerrville, don't know who you are. You have access to the alternator belt?

[Fly Boomer]

37 minutes ago, Falcon Man said:

Kerrville, don't know who you are. You have access to the alternator belt?

Calling @Kerrville ...

[Guest]

Sorry yall. I want be able to get to my plane for a week. I think if you measure the belt, which I will do when I get back, you can figure the belt without the part number. I wouldn’t go with what I measure on my J. You will want to measure your belt. 

[Pinecone]

If you take the belt off, pretty much any auto parts store has a tool to measure the belt and can well you the same Gates belt.

[haymak3r]

For what its worth. My belt is this:

on a 79 J

[A64Pilot]

If you want to go with an automotive belt, a Gates is a good belt.

However I’d go with their “Green Stripe” belt, I believe it’s a tougher, more expensive belt meant for high milage / truck, bus fleet applications, and of course we want whatever will last the longest.

Notice the “extra” belt in the top photo, an argument can be made that it’s getting old just like the one in use, but if nothing else it will likely get you home