97 Riv - rust in rear wheel wells

1997 Riv - 131,300 miles

Was having the brakes looked at today at a nearby auto shop, and the manager pointed out a RUST spot as I described to him from reading this forum.

Here is a cell phone pic of a spot on the INSIDE surface of the fender well (just above and behind rear rotor) behind the air strut. The rust can be chipped away and I believe it's a rust-thru condition and not just surface.

http://home.comcast.net/%7Eedwinn/LR_fender_well.jpg


Is that what enslow was talking about? or does rust form in another part of the wheel well? The top? or at the seams?


-Ed

That rust spot in the rotor is usually the same shape as the pad, caused by a vehicle sitting for a long time.....

Edwinn,

Sorry, I wasn't following this thread recently.

TechII, Edwinn's not referring to rust on the rotors, he's referring to rust in the wheel well. Edwinn, I can't picture where that location is in my mind, but I was referring to rust at the top inside of the wheel well. If this point rusts through, you can get water in the trunk.

Edwinn,

TechII, Edwinn's not referring to rust on the rotors, he's referring to rust in the wheel well. Edwinn, I can't picture where that location is in my mind, but I was referring to rust at the top inside of the wheel well. If this point rusts through, you can get water in the trunk.

Thanks for the reply.. I PM'd Tech II about the crappy cell-phone camera pic the other day. The vehicle is on a lift in the last bay which has a service door just beside it. The bright WHITE light is from outdoors. What looks like rust could be a reflection of the guy's shirt to my left, or the wall, cannot recollect what.

The rust spot is just above the fuel hoses and behind the air-shock but out of the picture. There looks to be a double wall of fender material there and that would be good. This type of patch doesn't have to look pretty.. just be solid. I may be able to fix it DIY.


-Ed

In my experience, the best paint I've used to stop rust is POR-15. It is normally applied directly to rust, as long as the flaking rust is removed. If it's rusted through, you may need to use some other technique.

I forgot to add one other check for rust. Check all your brake lines. I plan to POR-15 all my brake lines this summer. They are not leaking yet, but I fear that if I don't treat them now, they will.

About the brakes:

If you really do need brakes and you don't trust yourself to do pads, calipers, and rotors yourself, do make sure they install quality parts, even if it means you have to get the parts yourself. Don't accept their word alone that a certain brand is high quality. Make sure you are satisfied with the quality because some of the aftermarket stuff is really bad. I got ACDelco Professional parts and have been happy with them. I presume Raybestos Advanced Technology is good too, but expensive. Even Raybestos is probably good, but don't take my word on that.

Whether you do the brakes yourself, or you have the shop do them, I'd really suggest you do calipers AND pads. Everytime I have done pads only, I've had to do calipers 6 months later. On my father-in-law's car, the shop did pads only on the rear, and the parking brake stopped working. It turns out that the parking brake is built into the caliper which means the caliper had to be changed.

Have an update on the Buick Riviera body work, upkeep and restoration. It's been so flippin' HOT in the past month, and my garage faces south. Finally got back into the swing of it!!

Here's a better photo of the LR wheel well with RUST found after enslow advised looking back there. Wouldn't you know the Air shock (air strut) tube would be RIGHT IN THE WAY!! Was going to take an electric wire-wheel to it, but instead used a stiff wire brush.

http://home.comcast.net/%7Eedwinn/LR_wheelhouse_rust_III.jpg



Rust spot prepped.. yep it's a double wall in that area.

http://home.comcast.net/%7Eedwinn/LR_prep.jpg




A view of Rustoleum Primer brushed on the prepped area. Bottom of double-wall fender well (wheel house) was also rusted. Will get to spray painting it black another time. Anyone know of some good undercoat in aerosol can?

http://home.comcast.net/%7Eedwinn/LR_primer_III.jpg



Good thing for the Shop (Service) Manuals.. the three large volumes cover disassembly of EVERY part on the car. Was able to remove the wheel well molding and inspect the fender edges/flanges. View below after removal of built-up dirt on edge. No problem there!! :bananasmi

http://home.comcast.net/%7Eedwinn/LR_wheel_molding.jpg


Would really like to pull the rocker panels on BOTH sides to check for deterioration.


-Ed

Edwinn,

Sorry, I wasn't following this thread recently.

TechII, Edwinn's referring to rust in the wheel well. Edwinn, I can't picture where that location is in my mind, but I was referring to rust at the top inside of the wheel well. If this point rusts through, you can get water in the trunk.


Enslow was right!!

I got back to the vehicle yesterday and took the RIGHT (front and rear) wheel wells apart, removing edge molding, wheelhouse panels and rear aft covers. Here are a series of pics that describe RUST in the top of the wheel well.


First View - Top of RR Wheel Well

Found rust all right!! it's clearly visible in the photo below. Some of those spots are dried organic material..bits of leaves, etc.

http://home.comcast.net/%7Eedwinn/RR_wheelwell_top_01.jpg


Chipping at surface with a screwdriver

It didn't look bad at first, but the rusted area was actually 5 to 10x bigger.

http://home.comcast.net/%7Eedwinn/RR_wheelwell_top_02.jpg


Preparation for coating

After chipping and scraping with an old screwdriver, an electric wire-wheel was used to remove as much loose material as possible. There was more deterioration than first met the eye, and it could be even worse, i.e. more hidden rust in other parts of the wheel well.

http://home.comcast.net/%7Eedwinn/RR_wheelwell_top_04.jpg


Coated with rusty metal primer

This is Rustoleum Rusty Metal Primer brushed on from a half-pint can that we had sitting on the shelf. Might as well use it up. :wink:

http://home.comcast.net/%7Eedwinn/RR_wheelwell_top_05.jpg


Broader view of wheel well

Air shock, and rear bumper-to-fender seem in upper left.

http://home.comcast.net/%7Eedwinn/RR_wheelwell_top_06.jpg


The rest of the wheel well was ok

Left: looking forward along right side, Right: looking aft along right side.

http://home.comcast.net/%7Eedwinn/RR_wheelwell_views.jpg


What would be a good undercoat process to cover these areas?

Any additional procedure to repair/protect BOTH wheel wells? Who does this kind of work?


Thanks,


-Ed

So much for posting less. :disappoin


The body shop will be taking a look at the rear wheel wells, and a number of issues had to be addressed before the rear wheels went back on the other day. That goober of body putting (below) was really bugging me.. so I removed it!! The air tube is in a really bad place!

http://home.comcast.net/%7Eedwinn/goober_removed.jpg


Then slapped some primer on the spot. Looks like there was a weld or hole under there? Why putty over it?

http://home.comcast.net/%7Eedwinn/goober_painted.jpg



Crack in body seam

There are several cracks in the undercoating inside the Wheel Well body seems, and a 'thru-crack' in the lower forward RR wheel well, that is like behind the right end of the rear seat. Daylight can be seen through it. In the photo below, forward is straight ahead and the inside wall is to the left.

http://home.comcast.net/%7Eedwinn/rear_WW_cracks.jpg

I think this is actually jacking damage. Being careful to place the floor jack and jack stands according to the shop manual.. I seem to recall one time while positioning the jack CLOSE to the tire, a "crack" was heard but didn't know what it was at the time. This sh*t happened while servicing the air pump assembly.


Factory coating

The original coating is cracked in several places. If no rust is found there? coat it again?

http://home.comcast.net/%7Eedwinn/cracks_undercoat_1.jpg


http://home.comcast.net/%7Eedwinn/cracks_undercoat_2.jpg



How much repair work is needed in the rear wheel wells of a 16 y/o GM vehicle?

I'd hate to apply undercoat over top of hidden rust. IOW.. does it make sense to undercoat if there's still hidden rust?



-Ed

Update

Have some progress to report. The Riviera is coming along and is almost done, but I'm feeling a bit `high and dry´ as it's been out of the home garage for six days now. Somehow it seems that too many 'fixes' were defined / requested at one time, but I stopped by the body shop several times over many weeks, and communicated by email to lay the groundwork.


Undercoating

The wheel well rust removal and coating are done. It looks terrific!! They removed the shocks for this operation and reworked the areas I treated recently. The coating is a rubberized 3M product so it will help deaden road noise. Below are some prelim photos taken this morning in the shop's back lot.

The pic below is driver-side rear wheelhouse.

http://home.comcast.net/%7Eedwinn/undercoat_43.jpg


The following before / after photo is the forward wall of the REAR passenger-side wheelhouse where the CRACK was. NICE huh??

http://home.comcast.net/%7Eedwinn/wheel-well_cracks_II.jpg

This stuff is available in spray cans and I'm seriously thinking of applying to FRONT wheel wells to spiff-up and reduce noise.


Now I'm wondering if undercoating was the right thing to do

Assuming they hit all the existing rust spots, rust will still be there unless the affected metal is removed and replaced, yes? And what if other rust is forming under the existing hardcoat? Would it slow the growth? or simply hide it? How does rust form under the factory coating anyway? Is POR-15 a better solution? How about POR-15 with rubberized undercoat layered over it?


-Ed