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Thomasbus24
Administrator

USA
4544 Posts

Posted - 03/16/2017 :  05:41:45 AM  Show Profile  Reply with Quote
Can someone give me some insight as to exactly how one goes about checking for signs of impending failure?

We had one come apart today, the rubber belt contained inside it was laying on the ground. Tore up the serpentine belt and the fan blades. It's an AAFE so total disassembly required before we will know what else it took out.

Dealer says they are seeing these very frequently.

I'll post pictures later!

bwest
Administrator

United States
3820 Posts

Posted - 03/16/2017 :  05:43:43 AM  Show Profile  Reply with Quote
3126? There should be index marks on them in any case. I'd think the index marks will be off if it is beginning to "let loose".

Bryan
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 03/16/2017 :  05:54:12 AM  Show Profile  Reply with Quote
Nope...C7 I'll check for those marks on it though.
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BigPapa
Advanced Member

215 Posts

Posted - 03/16/2017 :  06:26:47 AM  Show Profile  Visit BigPapa's Homepage  Reply with Quote
There are no marks. They usually come apart from an oil leak saturating the rubber. It softens up and swells then starts to work it's way out. The only way I can think to inspect besides actually looking at it would be to feel and see if it's "loose" when your doing maintenance. We haven't had on fail like you said but we usually replace them if they have a lot of oil on them.
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 03/16/2017 :  06:39:35 AM  Show Profile  Reply with Quote
Dry as a bone, no sign of it ever being wet with oil. Looks like we got away easy this time, but I haven't gotten the parts bill yet.
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bwest
Administrator

United States
3820 Posts

Posted - 03/16/2017 :  06:42:52 AM  Show Profile  Reply with Quote
lol, didn't even realize who I was responding to, Pat. How many of those engines do you have? I don't have any FE or RE's so I can not relate to the accessibility of them.

Bryan
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 03/16/2017 :  09:31:39 AM  Show Profile  Reply with Quote
7 of these delights. Dealer says to forget about the kind it had that was held together with a thick rubber belt and spring for one that's fluid filled and be done with it. We are taking that advice.

We thought the bus had belt noise and planned to really look into it later on. Ooops. Lucked out there, aside from the ruined serpentine belt and fan blade, no other damage done.

https://www.flickr.com/photos/27265743@N03/32662120103/in/album-72157678115232623/

Not much to see but there it is.
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bwest
Administrator

United States
3820 Posts

Posted - 03/16/2017 :  09:38:03 AM  Show Profile  Reply with Quote
Wonder why it failed? Think road salt had anything to do with it? I have some 3126 and C7s that have that balancer. Never thought I'd see one come apart.

Bryan
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BigPapa
Advanced Member

215 Posts

Posted - 03/16/2017 :  10:06:31 AM  Show Profile  Visit BigPapa's Homepage  Reply with Quote
How many miles on it?
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 03/16/2017 :  10:17:37 AM  Show Profile  Reply with Quote
187,000 miles.

Certainly going to check out the other 6. I'm most curious if the twin is showing signs of failure...was 3 at one time but one got totaled back in 2013.
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slippert
Top Member

USA
630 Posts

Posted - 03/16/2017 :  11:23:01 AM  Show Profile  Click to see slippert's MSN Messenger address  Reply with Quote
The main things I look for on those are slippage, as bwest said... index marks are off if they have them, cracks in rubber, bulges or hernias sticking out... be it from being covered with oil or ?...causing deterioration of rubber/belting... When in doubt change them out...
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RonF
Top Member

867 Posts

Posted - 03/20/2017 :  04:25:59 AM  Show Profile  Reply with Quote
I've had 4 of them fail all of them on A3FE's. None had oil leaks and since I'm in the deep south I can take road salt out of the equation. If I remember correctly, I could take an crossmember loose on put it in that way.

US Army retired CMBT
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sambrutay
Advanced Member

United States
271 Posts

Posted - 03/20/2017 :  09:28:02 AM  Show Profile  Reply with Quote
we have these fail quite regularly. usually the first cold snap of the season. they happen in bunches when it happens. Of course we have 174 of these scrappy engines. We use a paint marker and mark a line through them and see if they move when they come in for inspection. but usually they come apart out on the road.

Bruce
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 03/20/2017 :  10:32:10 AM  Show Profile  Reply with Quote
Dealer says they have sold about 40 since new years. Aren't we lucky we have these engines? Oh well, I'd still take them over the MaxxForce messes!
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bwest
Administrator

United States
3820 Posts

Posted - 03/22/2017 :  05:17:50 AM  Show Profile  Reply with Quote
quote:
Originally posted by Thomasbus24

Dealer says they have sold about 40 since new years. Aren't we lucky we have these engines? Oh well, I'd still take them over the MaxxForce messes!



They didn't happen to say if their sales were all for C7 or are there some 3126s as well?

Bryan
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BigPapa
Advanced Member

215 Posts

Posted - 03/22/2017 :  05:36:31 AM  Show Profile  Visit BigPapa's Homepage  Reply with Quote
In the past 12 months we have replaced (5) on 3126E's, (1) on a C7, and (6) on C7 ACERT's.
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 03/22/2017 :  07:03:42 AM  Show Profile  Reply with Quote
Didn't get model-specific I'm afraid.
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ReliantDiv419
New Member

3 Posts

Posted - 04/06/2017 :  4:05:38 PM  Show Profile  Reply with Quote
I had 181 buses with the 3126E. I kept the "damper AS" as Cat calls them on my bench stock. Part number was 110-0366 cost in Feb 2016 was $687.92 up here in Alaska. 5 years ago they were only about$240 or so, but replaced them a lot. They were in the Thomas FE 2002 model year. We do our PMI's every 60 days and we would normally see them separating along the rubber. You would start seeing slight wear on the belts before they would go bad. Had a few sneak though our inspections and grenade on the highway. We would tear the front down and replace all gaskets while we had it apart. About a 2.5-3 day turn around. Got pictures if any one interested.
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bwest
Administrator

United States
3820 Posts

Posted - 04/07/2017 :  05:36:26 AM  Show Profile  Reply with Quote
quote:
Originally posted by ReliantDiv419

I had 181 buses with the 3126E. I kept the "damper AS" as Cat calls them on my bench stock. Part number was 110-0366 cost in Feb 2016 was $687.92 up here in Alaska. 5 years ago they were only about$240 or so, but replaced them a lot. They were in the Thomas FE 2002 model year. We do our PMI's every 60 days and we would normally see them separating along the rubber. You would start seeing slight wear on the belts before they would go bad. Had a few sneak though our inspections and grenade on the highway. We would tear the front down and replace all gaskets while we had it apart. About a 2.5-3 day turn around. Got pictures if any one interested.



Interested in pics! If you have an example of what they look like when you "catch" them before they "grenade" that would be of interest too. My Cat 3126 with the most miles has about 240k. Haven't noticed anything wrong with it yet.

Bryan
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 10/17/2017 :  07:22:35 AM  Show Profile  Reply with Quote
Failure #2...2007 with 163,xxx miles. This one didn't come apart, but it's not far from it.

New (upgraded, 1-piece design) balancer & related, new water pump & related (since it's been 6 years and we are RIGHT THERE, new belts and tension and a new alternator just for kicks. $1474.68

Initial driver complaint was a feeling of the engine cutting out momentarily. I'm not sold on the idea that this is the cause but it could have been. Outter part spins momentarily and catches hold again could give a weird feeling I guess.

In checking everything we heard and chattering sound at idle and got to looking, you could see about 1/8-1/4 wobble in the balancer at idle. Sits perfect on a cement floor, not so perfect spinning at 700 RPMs I guess.
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dferrell
Senior Member

102 Posts

Posted - 10/17/2017 :  1:21:46 PM  Show Profile  Reply with Quote
For what it's worth, we have a 2004 Blue Bird AARE with a C7 that the balancer has wobbled since it was new. It now has over 100k miles without issue. When we bought the bus new, I noticed the wobble and made a mental note to keep an eye on it and even marked the balancer to see any movement. It seems like the wobble is from the outer part being installed slightly crooked onto the rubber section. Anyways, ours definitely wobbles and has done so since new but has never been a problem.
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 10/18/2017 :  04:14:45 AM  Show Profile  Reply with Quote
One of the parts guys mentioned that it seems like they get a rush on these at the first cold snap of the year. Well the night before we were down to 35 at the garage (not that that's very cold). Made me wonder.
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