Ken Turner (Pipesusmc)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, March 05, 2005 - 12:56 pm: | |
From the MAK board (www.busconversions.com)
Posted by Jim Shepherd on October 24, 19103 at 20:25:36 PST:
I am going to publish this to the MAK Publishing Bulletin Board and the Eagle-bus-nut board. It is long, but I hope it will be of help to a few Eagle owners.
Being a retired belt “expert” (34 Years at Gates), I thought I should change the fan drive belts since I had the engine out in my Eagle 10. I went to my trusty catalog (’92) and darn if it did not list Eagle buses. It shows that the fan drive is the same for the 01, 05, 07, 10, and 12 models. The fan drive belts (two) are listed as Gates 449 and the generator belts are standard industrial 3VX450 (use three belts joined together – Gates calls them Powerband belts).
Wow, that was neat. Just bop down to the NAPA store and ask for their equivalent of the Gates 449 (most of their belts are Gates). Well, they don’t have a listing. I then checked with some of my friends at Gates and it turns out that they no longer make the 449 belt and nothing else they list is even close. Oh-Oh.
The Eagle fan drive belt is Eagle part number 054-0744-902. It is a matched set of SAE 11/16 (standardized automotive cross section) by 89 1/4 inches long.
Since our ability to travel down the road is completely dependent on these suckers, we need to make sure they are capable of doing the job. Unfortunately inspecting them is not easy – both in terms of the space and because of the type of belt used. The type of belt used does not do a good job of sending us a message that it is about to fail. Mine were notched belts and it turned out they had a bit of cracking, but they didn’t look too bad. However, they were worn pretty badly. The only way I could tell that was that they rode down in the grooves quite a ways and were just about to bottom out in the grooves. New belts of the correct cross section should ride about even with the top of the grooves. This is easy to inspect.
What to do about getting the belt. Well, I called a friend at Dayco who is a development engineer for automotive belts and he came up with a slick answer. He looked through his database and found that they make a belt for Caterpillar that is the same cross section and just a fraction of an inch shorter than the Eagle belt. The CAT part number is 8N-6693. He sent me a couple of belts to try and they work, but you have to do just a bit of slight of hand to install them.
I am not sure about all the Eagle models, but mine has the bearing housing mounted with four bolts and is not adjustable. All of the belt adjustment is taken care of by the idler. I might add that the idler is not the best design and only takes up a very slight amount of belt length for stretch and wear. This really makes it important to get just the right sized belt.
Back to the installation. Because the belt is a bit short, I found it necessary to remove all the bolts and move the housing towards the fan so that the belts could be placed in the gooves (DO NOT ROLL THE BELTS INTO THE GROOVES). Once the belts were in the grooves the bearing housing could be put back in place fairly easily and the bolts could be installed. As the bolts were tightened on my bus (could be a difference on different busses) the belts became pretty snug (without the idler in the tensioning position). This is great, since the belts were not fiddle string tight and all of the idler movement could be used to tension the belt as they wear in. Even if they were fiddle string tight, that is not bad, because new belts stretch a bit and wear in rather quickly. That fiddle string tight condition will go slack pretty quickly (less than 100 miles) and tension should be checked after run in.
One other important thing. The idler bearing needs to be lubed. My bus has a hose leading to a zerk that is well hidden over by the fuel filters. Be sure to give it a couple of squirts.
Hope this helps someone.
Jim Shepherd
Evergreen CO
’85 Eagle 10 |