Rear suspension turret rust / rot
 

Hi,

I own a classic imprezza - 1999 RB5

Low miles and always garaged - it hasnt seen a wet road for a long long time.

It has been waxed oiled every couple of years and generally shows minimal signs of rust / rot..

While giving it the once over, i noticed the inner rear suspension turret walls soft to the touch. The old wax oil was basically holding it together.

ive pulled the rot out, and it starts half way up, running up just below the rear seat belt.

Behind the rust, all the other panels are rust free and still covered in factory primer. The wheal arch itself is solif and rust free..

Ive read numerous posts on this issue, but the majority imply the rust starts at the rear arch and works up.

I'm inclined to think mine has started at the top near the seat belt and worked down though the centre of the panel, as the edges and bottom 2 inches are still solid. I dont think its spread up from the usual rust on the rear quaters.

I just wondered if anybody would advise on where it may of started.. So i can try and tackle the source.

thanks

Do you have any pics? What's the top of the turret like, where the top mount bolts are?

Hi,

No pics..

But this topic shows the panel.. It is litterally this part on the post below

https://www.scoobynet.com/general-te...d-through.html

No where else at all - everything else is solid and still primed..

Ive read a few topics about condensation, but i'm at a loss as to why its just this part.

I can repair it without issue, as there is enough on the edges to weld to.. its more a case of sussing out the cause, so i can try and stop this happening again.

Thanks

Glad you can repair it ok. As to what the cause is, it's more tricky. It's a complex area of folds and overlaps and bolt holes, with double skins, cavities and such like. My car '('99 uk wagon) is sound as a pound in the turrets, but the sheet metal in this area is different from the saloon. Condensation is one culprit, for rusting from the inside of the car - the rear light units tend to leak after time, allowing water to sit in the wells either side of the boot floor, producing a constantly humid climate in the aforementioned cavities and seams. I took my light units out and resealed them. The turrets appear to be double skinned, which will cause problems if there are any holes in the wheel arch side, like on US built newage cars:
http://forums.nasioc.com/forums/show...php?p=42752282
I'm sure if you fix it, paint it properly with loads of good paint, underseal the result, and keep the car dry inside the boot, you'll be ok. Whilst it's all apart, treat the seam between the outer rear corner panel and the inner around the wheel arch, this is where the arch rust starts (thanks to 328isport)
https://www.scoobynet.com/projects-4...l-project.html
Good luck!

They start at top and work down like you have discovered, by time they are bubbling arches there complete mess.

Joys of multiple overlaps and only spot welded, not seam welded same as any other modern car. There is no weld through, or even basic, primer on when assembled. Only time before moisture seeps past seam seal from either outside or inside.

Thanks for the responses..

Much appriciated

Regards

Just an update on this..

I spent today sorting this i think i have found where the water enters...

On the door / C pillar moulding, at the bottom of the window screen there are 2 small plastic grommets holding the moulding to the C pillar. I removed the grommets / moulding and there is rust around the holes where the plastic grommets enter.. I'm 99% sure this is directly above the rusted panel, and would explain why a car that gets washed but not driven in the wet has the issue.

Well spotted. I'll have a look at mine tomorrow. Those holes can be used as access for some cavity wax.