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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: jav9956 on March 21, 2016, 10:55:32 AM

Title: Cracking in roof welds normal?
Post by: jav9956 on March 21, 2016, 10:55:32 AM
As I was sanding, cleaning, painting the ceiling studs this weekend I noticed numerous cracks towards the back of the bus. The cracks are at the welds. There are 2 in a row on the passenger side of the bus and 4 in a row on the drivers side of the bus. I pictured one here. It is a little wider than the others so it is a little easier to see.

I hate to see something like this but I am wondering if it is unusual? I know the bus is old and over time can understand how something like this may happen. I am unsure whether this may be the sign of a bigger issue occurring with the frame being that the cracks that are occurring all in a row on there respective sides (in a row being the same location from one vertical stud to the next, in the same location on each). Obviously the crack is not all the way through the pipe so, who knows, it could have been this way for years.

Is the best line of action to re-weld this joint and move on? Any thoughts on whether I should treat these as isolated issues are look for a bigger root cause?

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi277.photobucket.com%2Falbums%2Fkk53%2Fthebear_09%2FP3200125.jpg&hash=9a7badcfb98376d64d320dcf538587e7fca99d99) (http://s277.photobucket.com/user/thebear_09/media/P3200125.jpg.html)
Title: Re: Cracking in roof welds normal?
Post by: Brian Diehl on March 21, 2016, 11:21:55 AM
I found the same issue on my bus on two ribs in a row on the back driver's side (1985 96A3).  It appeared to be where someone had hit an overhead obstruction as the skin had a slight dent in it.  I simply ground it out, welded in the crack and then put a piece of 1/8" steel strap across the joint and welded it in.  Problem solved.
Title: Re: Cracking in roof welds normal?
Post by: jav9956 on March 21, 2016, 11:36:25 AM
Simple enough, I will likely do the same. Good to know you experienced the same issue. I was pretty surprised when I saw it on a total of 6 welds. But as a whole the joint still seems to be holding on quite well.

I will put my mind at easy and go for the simple fix.
Title: Re: Cracking in roof welds normal?
Post by: Scott & Heather on March 21, 2016, 11:46:17 AM
My bus didn't have those. Would have made me pause if I had seen that though.


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Title: Re: Cracking in roof welds normal?
Post by: buswarrior on March 21, 2016, 11:53:17 AM
Fred Hobe said there was lots of that sort of thing in MCI roofs.

Weld 'em up, gusset the ones you think might be important, carry on...

happy coaching!
buswarrior
Title: Re: Cracking in roof welds normal?
Post by: DoubleEagle on March 21, 2016, 12:28:41 PM
All of the buses flex a bit, so cracks can happen, but those welds look like previous repairs that were not so good. Wrong welding rod, amateur welder, etc. Grind them down, vee the cracks, and use a rod for rusty metal like 6011.