Rust
 

My '85 300D has an increasing rust problem at the right rear quarter panel. Turns out that this was replaced at some point and was either a cheap/used/not properly prepared component. The bubbling is in several locations and the worst area is just behind the rear door.

Anyone have one of these replaced and have a sense for the cost? Since the entire quarter panel needs replacement I do not feel in a hurry as my 16 year old drives this car now and it might see some other damage before too long. But the car is a tank and I will probably lean toward fixing it.

If you get to it before it goes to far then a good cleaning followed with some POR15 should stop it.

I had a '68 220D some 10 years ago that was going bad in the quarters. I got an estimate from a body shop to do a complete quarter replacement, all the way up into the 'C' piller. Seems it was somewhere around $1500 per quarter at the time. (I think that price included the replacement panel) I almost went for it, as much as I liked the car. But then the trannie went, and it quickly became too much to fix.

This is bubbling thru in 5-6 small places and really bad in one place. Not familiar with POR15. What is this?

Other problem is that I have enough dumped into this car that I can only logically keep it driving until it really dies and I think that is a long time away.

The paint bubbling can be two types of rust though, it can be already through the metal or just surface rust.
http://www.por15.com
They have stuff to stop it and to fill the holes if you so desire[Remember you can't bondo over holes.], at the very least it should buy you some more time.

Thanks
 

Great resource, thanks.

Especially since I have a boat too. I had not heard of this company.

No problem. As for buying it, it is a good deal cheaper on ebay normally so it is worth a look going there before ordering.