Finally got around to getting the write up done for this.Full version with pictures may be found here. It is a PDF file so you will need Adobe Acrobat PDF reader to open this file.

Cracked frame repair

Some pictures from the write up.

Crack in the frame:


One can see the amount of frame working by the ripples at the crack.


Crack ground out and welded


Fish plate cut and ready to install


Fish plate installed


Concept drawing for the stiffener


Stiffener fabricated


Stiffener installed



Big job BUT REALLY improved the handling and steering response. Very little tail wagging now even though it is still tail heavy. Because this area now is so stiff, there is a bit more NVH (noise, vibration & harshness) but over all well worth this small issue. I can only imagine what it would have like if the frame had cracked all the way through.

Will watch all this area closely as I am well aware of fixing things and creating other issue.

Finally a bit of fun to drive.Not as much work.

Wow...
Looks like a great job. Engineering seems sound to me. Time will tell! The fact you can FEEL the difference says things were indeed floppy before.

Good thing you noticed it. (These things are like old airframes... good to check for cracks now and then!)

My old Pee chassis has the extra 8 inch rail on top to clear the tag axle, I assume it makes the frame stronger overall. I have looked at mine (esp the front near the engine/trans!) seems OK and very light rust. So far, so good!

nice writeup!

It looks like your locator (radius) rod, like mine, has solid bushings rather than rubber. Spartan seems to have changed to the solid around the time ours were built.

quote:

Finally got around to getting the write up done

Excellent, professionally done tutorial!

Very extensive write up on the repair, great job very professional, true craftmanship. One thing is for certain it will never crack in that spot again.

You have to feel great that you found the crack, and now the job is complete.

Enjoy!!

You my friend are one smart dude. I just have one ? Why is it called a fish plate.?

Tom Taylor

Nice.
Nothing like welding under a vehicle.

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Nothing like welding under a vehicle.

I remember one time, when my former step-son had turned 16, he and his buddies would go muddin'....he would get the underside of his pickup completely caked with mud. I told him, it wouldn't be fun if he ever had to work on his vehicle with all that mud on it....but you know how well teenagers listen....

A couple of months later, his u-joints went out. He was out in the driveway, laying under his pickup, replacing them. I walked up, slung my foot on the bumper and what seemed like about half of that caked on mud fell out from under that pickup on top of him.........

experience is such a good teacher....

quote:

I just have one ? Why is it called a fish plate.?

Tom Taylor

The term original term "fish" came from the shipping industry where the "fish" was used to strengthen the mast.

Later the term "fishplate" was used in the railroad industry and described a plate used to join two rails together. could be either bolted in place or welded in place.

SO, joining two pieces together or strengthening a joint or repairing a crack with a plate, the plate may be referred to as a "fishplate".

Some people also refer to this type of repair using a plate as a "scab"

quote:

shipping industry where the "fish" was used to strengthen the mast.

did they actually strap some fish onto the mast to strengtrhen it?

By Dick Dubbs:

quote:

did they actually strap some fish onto the mast to strengtrhen it?

Only on the GILLig chassis, Dick...

Lou

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Only on the GILLig chassis, Dick...

Lou,

Are they STEELhead fishplates?





Kirk

So I have been quiet because I've had other things keeping me busy

Let me make this perfectly clear if you have not checked your frame and have a similar configuration please do it as soon as you can. I knew my coach had a $7000 frame repair a while back and when I saw MWrench's posts I suspected what I found. My Coach had exactly the same break. My uncle did not have the necessary equipment to repair the damage. Now they did things in a big way. That's why $7000. Because of the tight space you will have to visualize that they made a piece to fit inside the existing frame. The piece has been extended well past the ends of the springs.

The Dbarth was disassembled, the piece inserted and welded in. All bolt holes re drilled and everything reassembled.

I just want everyone to be safe. Thinking about this the most beneficial thing that any or all of could do is drive each others coaches when we have a GTG.

We could all say why does yours feel different, looser, sharper, harsher, stiffer, spongier?

What is that noise or vibration?

Why doesn't yours have that noise or vibration?

That's not what my pac brake does.

Your brakes feel far different than mine.

How do we know normal if ours is the only one we have ever driven?

My coach handles far different than any other diesel I have every driven but none of them were ever a Coach.

Enough rambling pictures of my repair. Be careful!

I am going to post this here and start a new thread named. Have you checked your Coach?




You can see the welding at the crack in this picture!

You can see how far they extended the piece they fitted in. This is toward the front of DBarth.

Another shot of the crack site.

This is where the rear of the internal piece ended.

The plot thickens...

I was somewhat surprised to see another frame crack at the same location. It seems that the factory goofed on this design. Placing the sway bar attachment between frame cross members (not supported at the attach point) is asking for trouble. Then they use rigid ends on the bar. (Rubber ends would transmit less shock but allow too much play I guess.)

Even experienced vehicle producers screw up now and then. Has the factory had anything to say about these problems?

Good advice from Dana: get under those coaches and look around!

Yes I think this was a major screw up by Spartan! No comments so far about this from them. The placement of the bar and the length of the bar all have some contribution to the problem. There is a lot of stress caused by the springs and the bar working against each other.

Dana you might crawl back under there and and have some one go to the rear of the coach and start to push back and forth to start the rear wobbling. Watch the ends of the bar to see if there is any movement in the bearing ends. Yours appear to be the earlier design rod ends and may have grease zirks as my original did. The newer rod has sealed bearings and are not serviceable. My original rod, replaced years ago had at least 1/4 inch play in each end.

Now that I have fixed the frame and stiffened the attachment area, I will be watching for other issues to appear.

I don't like the design but right now I have no idea how to improve. I will take some measurements later and then analyze the diff movement to see if there is any way to lessen the fight between the spring movement and the panhard rod.

I also am looking at how to move the air bag assist to the rear of the axle. Their placement is not ideal as it take a lot of pressure to assist and their effect is very limited currently. Right now the shocks are in the way. More on this later.