Tip on how to fix rusted through body mounts?

Hi all,

From Norway here. This is my first post. The wife has been after me for years now, demanding I get rid of the motorbike, since it's so dangerous, according to her, and since happy wife is happy life... Well, a man need something in the garage to play with, so if the bike has to go, I need something new. In comes the the 1999 Jimny, a manual with 130K and a more or less like new looking leather interior, likely from a later car I guess. There is no aircon and no ABS on this, so not much that can go wrong, I hope

The car is in reasonably good shape I think. I have removed the plastic trim that covers the outside wheel arches back and front, and the inside covers in the wheel arches in the front. I haven't found anything to worry about, except for the two rear body mounts.
There is a bolt/pin mounted in the body, going down through a bush, then through the mount in the frame, and another bush. The area around the bolt (in the body) is pretty much rotted out. There is a hole on the right side, about 5 cm in diameter, and one about 3 cm on the left side. These are also close to the bolt. The mount in the frame looks to be good.

Now, how to fix this? I need to lift up the rear of the car body a bit to get access. Then the question is if I should try to cut away the rusted plate and weld in some new, or just try to replace the affected body panel?

Jimnybits sell this one: www.jimnybits.com/62130-81aa4-genuine-me...inr-98-18-no-15.html

Here it's easy to see how the bolt that secures the body to the frame is fastened, and I can see when looking at it that the rust more or less rotted away half of that piece that reinforces that pin. I hope all this makes sense.

What to do? Go at it and try to cut out what I can and weld in new pieces, or how difficult is it to drill out the spot welds and mount a new piece like the one jimnybits sell?

I may add that I've done a fair bit of welding in my time, but that was in the 90's, offshore industry. I quit that business, and haven't touched a welder for 30 years now. Neither have I done any welding on cars before, so this is going to be fun I could of course take it to a garage and get it fixed, but I would like to try to do it myself. It's not a daily driver, I just like to spend time in the garage

Appreciate any advice you can give me Thanks!




 

Hello and welcome.
Afraid I can't answer your question, but I'm sure someone who has done that repair will be along in a while to offer advice

The problem with body rot is that it's always worse that it looks at first. Basically you just need to start cutting out the rust and see how far it goes. You'll probably end up with a terrifyingly big hole. Once you have cut the rot out you can plan out how to go about the repair. Before you start cutting undo the bolts then bash some wooden wedges between the body and the frame. You want to increase the gap a little. Once you have finished the mounts will compress a bit under load so you need to compensate for that compression before rebuilding the body.

I haven't done those particular mounts but I did some work under the rear wheel arches which may give you an idea of how it is constructed inside. www.bigjimny.com/index.php/forum/18-buil...-laner-build?start=0
I did the ones under the footwells a little while back which again may give you some ideas. You'll need to scroll down to near the bottom of the page. www.bigjimny.com/index.php/forum/18-buil...laner-build?start=84

What sort of welder do you have? Jimny body work is really thin so mig with 0.6mm wire is a pretty good way to go. Don't even consider gasless mig. It's really easy to blow through the panels when you are welding so be prepared to settle for welds that are a bit ugly as long as they hold. I prefer butt joints where possible. They take more preparation and are a bit more tricky to weld but they are less likely to rot later. Lap joints are easier but no matter how careful you are with seam sealer and cavity wax, water always seeps between the layers and causes rust.

If you are keeping the car fit a new panel 
This will be quicker/easier than fabricating plates 
Have a google for parts in Europe this may save you some money

  www.suzuki-diely.sk/product/sk/vystuha-podlahy-jimny-1

Says they have no stock.......maybe they just order on demand 

Hi Les!

I don't have a welder yet. The plan is to pick up one next week, and likely a 180amp one. To go with this I'll get some 0.6 and 0.8mm wire, and an assortment of body sheet metal of different thicknesses to practice on. I'll buy an 11 liter bottle of ArgonMix to go with this. does this sound ok?

It sounds like the best thing to do. My worry was that if I start drilling out spotwelds I'll have to remove other "details", or panels, in order to replace this rear panel. At first glance it seems this one is connected to the rear floor, then there is one behind it to the rear, and and a smaller one at each side. This may have to be removed. I'm not sure. I'll have clean things up a bit first, to try to get an overview of what might be in the way.