While working on my 1989 MCI 96A3
While preparing the framing for a new plywood floor, I discovered two cracks. (the area is circled in red in the bottom picture)
I am a pretty good welder and sheet metal worker.
What I want to do is V-groove the cracks and weld them, then weld in a 1/4"
Gusset plate where I have drawn it in.
I would also plate them, but I need to lay the Plywood floor flat in that area.
Any input or suggestions would be appreciated.
I have examined the rest of the frame and could not find any other cracks.
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.peterbylt.com%2Fmotopics%2Fcrack.jpg&hash=4cbe9f465ac3bd2dbf805611f2f47d436133beb9)
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.peterbylt.com%2Fmotopics%2Fcrack2.jpg&hash=6ef596c47a7a7037d55a4a1e2a69887666eb98ea)
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.peterbylt.com%2Fmotopics%2Fcrackgusset.jpg&hash=eb6474375566bcf35d7fe62e470e8de595061f09)
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.peterbylt.com%2Fmotopics%2Ffloor1crack.jpg&hash=35f7bb754b2fe3faa352f1ae427a48b72e0c3d79)
Peter
That is a common place for a MCI to crack because of the engine,gusset the inside and grove the top out and weld it will be ok
Am I missing something here on the no photo view, whats up with the board.
Regards
Floyd
Cannot see pictures either.
JC
Strange the photos were there a few minutes ago he had a line between the cracks real clear photos
Would be nice if photo posting issues would be corrected including the restrictions on their sizes. I know there are several workarounds, but most here are unable to deal with the problems.
I also realize that we use this site for free and should be grateful the host spends his time/ money to keep it going.
Those pictures are being hosted on another site and the problem is with the other site not this one.
Quote from: Jim Eh. on August 07, 2016, 02:47:17 PM
Those pictures are being hosted on another site and the problem is with the other site not this one.
Sorry, my fault, the pictures are hosted on my own server, and I was hacked over the weekend.
It is back up and running.
Peter
The pictures show fine now. Your idea of a gusset plate to reinforce so the top remains flat should work, but in some situations, when you reinforce an area like that a new area takes the stress load and new cracks might appear elsewhere. If Cliff has done this type of repair before and all is well, then you are set.
He is doing it right his idea is the same MCI used to repair those cracks, the 2 forward tubes on a angle is what causes those to crack to much stress transfer
Fwiw his cracks are not as bad as some I have seen on MCI's in that spot
I had considered putting an X brace in the entire area in back of the cracked member, but decided the Gusset plate would do a good job of reinforcing that area.
Thank You for the feedback on my proposed fix.
The next step is to get an extension cord big enough and long enough to get my Welder up into the Bus.
Peter
I think its going to be that way, the forces could use more area to flex because it is confined. I vote more area as you mention, good call.
I might lift the welder with a cherry picker and run the cables through.
Floyd
At the end of any cracks drill a small hole to stop any further cracking. Even if you are welding the crack, drill it to relieve the stress and stop further/future migration of the crack(s). Oh and make nice rounded corners on your patch plates.