Advice on repairing undercarriage damage (and adding skid plate)

[thor452]

http://www.skinzprotectivegear.com/snowmobileproductar/floatplates.html

 

[steveg_nh]

I was just about to order a Yamaha one, but this one from Skinz seems like it covers even more. I assume it's designed to let the front suspension arms have their full range of travel without hitting it. Does this one mount any easier than the Yamaha one? Just thinking about the area I have some mangled metal.

 

[thor452]

it allows for full movement and mounts quite the same way is more protection and gives the sled more flotation off trail and in fresh powder.

 

[DGZRT]

The skinz one does cover more but if you ride in deeper snow the front by the "A" arms holds more snow and you can develop build up under the plate from it melting . Just an opinion...

 

[steveg_nh]

Thanks. I'll probably stick with the yamaha one.

 

[steveg_nh]

I'm a very happy camper tonight. Leaving this belly pan as is would drive me crazy. I just don't like broken stuff. Anyway, talking with one of the TY sellers I've been using a lot the last couple of weeks, henseljg2, he had a used belly pan that I could swap out mine for. My heat exchanger is barely bent, so I'm confident I can leave it as is, and replace the belly pan to get back into shape. Then I'll add the Yamaha skid plate. Whew!

Here's the new belly pan on it's way to me! I may put the metal insert/cover from Barn of Parts on too, as added protection...

Jim, thanks as always!

 

[Teamblue4]

henseljg2 is a great seller.

 

[yamadoo]

You are going to have one nice sled when you are done.

Hope you have fun and many safe trouble free miles with this sled.

 

[steveg_nh]

henseljg2 is a great seller.

He sure is. I feel like he's become my personal used Yamaha parts consultant. Really great guy and seller. And he packs stuff so it could make it to you in one piece even if it got caught up in an earthquake. I wish all seller's would learn to do that.

You are going to have one nice sled when you are done. Hope you have fun and many safe trouble free miles with this sled.

Thanks. That's my goal. In hindsight the sled had a few more issues than I would have liked, but except for one leaky tunnel heat exchanger, nothing has been mechnical. That seems very solid. This is the time to swing the wrenches though, when it's 80 degrees out, not 8!

 

[steveg_nh]

Well, coming back to this project now, as some of the other stuff is behind me. I got the sled up on ramps so I could move around, and while planning out the project to swap the belly pan, I decided I actually am better off with it as is. If I put the new one in, nevermind the work to get it in, I would have 3 rivets on the heat exchanger that would no longer be able to be riveted to the belly pan. Granted while bent, it's still a solid unit and it all lines up.

So I decided to leave the bent pan in, for now. I put in Barn of Parts' metal oil panel, and redid all loose rivets on the existing belly pan. Some were worn to almost nothing. 3 of them, the heads came right off with a screwdriver, no drilling needed. It is very solid now. In addition to the metal BOP plate, I have the Yamaha skid plate. I found the 4 rivets I'm supposed to remove to make room for the rivnuts do not line up. They are close, but not there. I decided to leave those rivets alone, and relocate the holes for the skid plate about 3/4" away from the corner rivets, in all 4 corners. I will drill new holes entirely, and use well nuts. That way I'm not weakening the belly pan structure with well nuts, but won't mess around with the rivnuts. I plan on using the Yamaha screws that came with the kit.

So off to Lowes or Home Depot later to find the right size well nut.

I'm getting there...this sled is a test of my mettle.

 

[steiner]

Careful where you drill. There is a coolant line that runs along the back.

 

[steveg_nh]

Yup. I used an inspection camera to look around a bit with the oil change panel off.

I went and bought the well nuts though. The 1/4-20 is about the same size bolt as the 6mm that came with the skid plate. But the hole required for the well nut worries me that it’s too large for the frame area. I need to look up on other threads what size people were using. #10 seems too small.

I wonder why my rivets didn’t line up with the skid plate holes. Is that common? I don’t see any bending at the corners that changed their locations.

 

[steveg_nh]

For the skid plate mounting I’m trying to think of my options. I won’t use the rivnuts. Hate them. I could rivet but pain to remove each time. Well nuts may need a hole bigger than I’m comfortable with. Belly pan is too thin to tap. I was thinking the stainless self tapping Robertson head trailer screws I have. They seem to hold quite well in thin walled aluminum tubes on a trailer. Thoughts on using those to mount the bottom of the skid plate to the belly pan?

 

[Winderallday!]

Skid plate hole pattern is off for sure, I had to elongate/open up the holes in the plate quite a bit and use flat washers on the pan head bolts. The two thicknesses of aluminum do give sufficient thread if you decide to tap the holes, but recommend you use a smaller than normal tap drill size if you decide to go that way. I tapped the holes used by the rivets on my sled, but they do eventually strip out because the holes are too large to give full threads like you get with the proper size hole.
I will be putting in riv nuts this year in place of the tapped holes, but not the ones that come with the skid plate kit, as the grip range is far too small, so I bought the next size up grip range riv nut made of steel vs aluminum.
I use a metal sleeve over the drill to serve as a stop when drilling up into the frame so as not to hit something sensitive.
If you have the room for the drill point on the end of the self drilling/tapping screws, then they should work too.

Cheers.

 

[gitrdun]

Agreed, skid plate holes were slightly off so I think I used a chainsaw file to make them exactly right to comfortably fit the Yamaha body panel bolt in the picture. I use that Philips bolt because it has a flat head and less likely to grab a rock and cause damage. I did use rivnuts, and as Apexallday! says, you have to use the up to 6.6mm grip range because the kit used to come with the up to 4.2mm grip range, and guys were complaining that they were coming loose. You will notice that there are two thin pieces of metal that the rivnuts go through, that's why you have to use the 6.6mm range rivnut(aluminum). I'm guessing I've had this combination on for 8 years and works perfect. I torque the body bolts to 25 inch lbs..