[Intuit]

I was weighing the better option. RTV sealant, or one of the various (non-paint) spray-on undercoats. Any difference between the "aero-rubber" (Bondo) and "rubberized" (EverCoat) ? Anyone with any experience with these brands ? Who's best ? EDIT: http://www.feoa.net/modules.php?nam...5&start=0&postdays=0&postorder=asc&highlight= /EDIT

Basically looking for the stickiest, thickest and most durable shyiat that'll almost literally survive hell or high (salt) water.

I know that RTV can be some nasty stuff, but application would be far less convenient and haven't looked into how/where to acquire enough of it. Probably need to acquire a sealant/caulking gun and tube from a hardware store; best guess.

But the undercoat that is already on the bottom of the vehicle, sides of the strut towers, and under far worse conditions, has held up beautifully. So what are your experiences and thoughts ?

BTW, the layers of rustoleum primer that I laid on there seems to have held up decent enough that I don't need to patch the tower. (but still need something better than just paint)

Would be nice to have a shaped/molded plastic insert to go over that planned undercoat or sealant.

=============
On a side note, I'm pulling the rear back apart sooner than I intended. Started hearing a noise after a highway crater. Kind of like metal tapping on the back frame-body. Strange thing about the noise, only occurred over seduction (sinks into the road) bumps. Compression (raise off the road) bumps no noise. After some investigation, noticed rubber shavings sitting on top of the strut tower without the noise. Looked closer and noticed the rubber bushing there, on the replacement strut assembly had dry-rotted and was shearing. The bushing for the other side was just about gone; the strut bar crooked. So the noise I was hearing, was the strut-bar making contact with the strut mount or other, up top.

 

[98EscortDude]

I have used the Rust-Oleum brand Professional grade undercoating. There are two different ones avalible, one being "pro grade" and the other being cheaper but not as good i guess. I like the stuff and its also a rubberized undercoating although it dries to be pretty tough and hard. Also the spray can can be used at any angle even completely upside down which is nice for getting into tight spots.

 

[white-lightning]

:agree: I used the same stuff to redo the undercoating in my wheel wells.

 

[Intuit]

Thanks for the tips guys. Looks like I may need a patch/reinforcement job after all. I think multi-layered steel (MLS) was used for the strut-tower cap; and/or maybe iron. Anyway in some places it looks like I'm down to either a few layers or a single layer. Pieces of a rather thick layer came off with one of the struts and it's no longer steel or iron... but like a stiff, brittle carbon. (all black like volcanic rock on the inside)

My plan is to take molds of the inside, then outside of the towers. Have the body-shop guy fabricate an insert and overlay. (stainless steel if possible/practical) Then I can put in the insert, overlay, drill holes through them, and use stainless fasteners.

Right now pondering on a good way to develop the molds that I'll need. Suggestions are appreciated... (aware of possible inside of strut tower clearance issues)

BTW, think I'll have RTV between the reinforcement layers and original body. I'll use one of the overcoats for the exposed sides of the reinforcment "plates."

 

[madmatt2024]

Its not iron, I can guarantee that. That seems like alot of work to go through, not to mention it isn't the correct way to repair a strut tower. In my opinion, fasteners aren't an option when the part your repairing/replacing is structural on a unibody vehicle. The only safe option is to weld parts in.

If you are looking to protect the tower itself then you will need to remove the struts and clean all the rust off. Then I would suggest painting it with a product like POR 15 or Rust Seal. You could also do self etching or epoxy primer and undercoat it.

 

[Intuit]

Thanks. That's probably what the body guy will tell me when I run it past him Monday. (on vacation this week) The reason being that fasteners allow for possible movement, where-as welding does not.

Didn't know what "self-etching" was but Googled it. Bonding solution then undercoat sounds like the far better route. Thanks again MadMatt...

 

[madmatt2024]

Self-etching basically means the primer eats its way into the metal. The link you provided is for an industrial solution however.

 

[Intuit]

Reminds me of those circuit board kits where you use pencil graphite to trace out your circuit paths, then use the etching solution to eat away everything else. (IIRC might've been ammonia eating at copper)

Is there such an independent etching solution that would help clean-off those strut wells ? I'd rather handle as much as is possible myself, so that it doesn't end up sitting for 3 weeks waiting to get done in the shop. Other reason is so that I may limit exposure of other parts to this chemical.

 

[Obliterous]

A small media blaster gun using crushed walnut shells will strip everything off, leaving nothing but bare metal, ready to be primed.

Use a good automotive primer, your paint shop can recommend one that will inhibit rust.

 

[madmatt2024]

Is there such an independent etching solution that would help clean-off those strut wells? I'd rather handle as much as is possible myself, so that it doesn't end up sitting for 3 weeks waiting to get done in the shop. Other reason is so that I may limit exposure of other parts to this chemical.

Sure, they make a stand alone etching solution. Its a phosphoric acid biased solution you spray on the rust. It will cut through most surface rust but rust scale will have to be removed manually.

 

[RoadWarrior]

I've used the old formula "CLR" for it's phosphoric acid content, but they reformulated it without now. But next to it on the shelf in Walmart you can usually find some similar stuff that still has the phosphoric acid in it. It just passivates the surface rust.

For 3rd gen caravans, there's a repair kit for shock towers that is epoxied over the top of the original. I'd be inclined to just cut towers out of a good front end and have them welded on over the top.

Rust won't come back or can't continue if the surface is completely sealed. Thick stuff like bedliner can work if you coat it well enough.

 

[EscorGo]

Eastwood has everything you could ever need shy of sheetmetal parts

I rust converted, coated, etched and painted my underside. Then I soundproofed the flooring.

http://www.eastwood.com/

 

[Intuit]

Thanks for the help, all.

EscorGo, that may come in handy as the spare tire wheel well is rusting out around the ports. (forward-most of three completely gone) May eventually patch and protect that. But even some heavy aluminum and JB Weld would work since there's no need for the added strength & support that steel is meant to provide.

=============================

FINAL RESULTS !!!

After closer inspection (see pictures linked below) it became evident that the factory had welded a reinforcement plate/ring to the body (underside) of the rear strut tower cap. It was actually that plate/ring, that was coming off with the strut tower. The body though deteriorating where the plate broke-away, was completely intact. That reinforcement plate / ring, needed to be replaced, and the body above it, strengthened and protected.

Seatbelts, seats, virtually everything except speakers and wiring, I stripped out of the back in preparation for the work.

After coordinating with Mike at the following shop...

Sawyer Body Shop (a.k.a. Beast Worx)
1946 Shollenberger Ave.
Cincinnati, OH 45239
513-542-RODS (7637)

...they had the replacement plates fabricated, welded, undercoated and ready the next day. Good work at very reasonable price. Worth the drive if you're hours away. If you speak with Mike, Dave, (Rob does the paint), let'em know Marc referred ya...

Pictures taken...
http://cid-0c43f28d3024191b.office.live ... 190126.JPG
...notice how only a few threads are showing for the strut-mount, as opposed to before service. The fabricated reinforcement plates are thick. Rear sat much higher before I loaded it back down.

Car has been through some "incidences" so the rear alignment was off to begin with, but much improved since the plates were installed.

Rear-L
Camber -0.8 (-1.5 0.5)
Toe -0.07 (-0.05 0.25)

Rear-R
Camber 0.8 (-1.5 0.5)
Toe -0.04 (-0.05 0.25)

Rear L+R
Cross Camber -1.6 (---)
Total Toe -0.10 (-0.10 0.50)
Thrust Angle -0.01 (-0.40 0.40)

 

[zzyzzx]

FINAL RESULTS !!!

After closer inspection (see pictures linked below) it became evident that the factory had welded a reinforcement plate/ring to the body (underside) of the rear strut tower cap. It was actually that plate/ring, that was coming off with the strut tower. The body though deteriorating where the plate broke-away, was completely intact. That reinforcement plate / ring, needed to be replaced, and the body above it, strengthened and protected.

Seatbelts, seats, virtually everything except speakers and wiring, I stripped out of the back in preparation for the work.

After coordinating with Mike at the following shop...

Sawyer Body Shop (a.k.a. Beast Worx)
1946 Shollenberger Ave.
Cincinnati, OH 45239
513-542-RODS (7637)

...they had the replacement plates fabricated, welded, undercoated and ready the next day. Good work at very reasonable price. Worth the drive if you're hours away. If you speak with Mike, Dave, (Rob does the paint), let'em know Marc referred ya...

Pictures taken...
http://cid-0c43f28d3024191b.office.live ... 190126.JPG
...notice how only a few threads are showing for the strut-mount, as opposed to before service. The fabricated reinforcement plates are thick. Rear sat much higher before I loaded it back down.

The rust in those pics really don't look so bad, at least compared to some of the other rusty strut tower pics I've seen here. That and I really can't tell what you are referring to when you speak of th "plate" thing,

 

[Intuit]

The initial pictures don't do it justice. The problem is that the metal ring's structure, internally, has changed so that it is no longer metal (or rust,) but a pure black, brittle, carbon-like, charcoal-like substance.
http://en.wikipedia.org/wiki/Carbon_steel

This picture illustrates what I'm referring to:
(Photo Link - click me!)
The big chunks sitting on top are the pieces of that ring that came from the bottom of the strut tower.

The following is the best shot of the reinforcement ring:
(Photo Link - click me!)
You will need to turn off your web browser's automatic image resizing feature and click the image once/twice, but you can get a real close-up of underbody vs the reinforcement ring. This is a *very* high resolution photo. Over toward the bottom right of the image where the mounting hole is, there is no reinforcement plate/ring. The top-quarter part of the image, there is. The thick black jagged line separating the top and bottom, is where the reinforcement ring has torn away.

Here's marked photo:
(Photo Link - click me!)
Red outlines the damaged reinforcement plate/ring.
Blue outlines the strut mount fastener hole.
Green outlines the inner-parameter of the strut tower.

 

[madmatt2024]

That isn't a reinforcement plate/ring its rust scale that has built up between the tower and the strut mount. All that junk needs to be chipped off and the tower etched and painted. Then a new strut mount needs to be installed.

 

[Intuit]

Nope, wasn't "scale." (way too thick for that, identical on both sides, raised well above the normal body surface) Like I said, the photos don't do it justice. If you were there, you'd know. But yes, the body shop of course removed the old reinforcement rings prior to installing the custom fabricated replacements.

 

[madmatt2024]

Nope. I have seen scale that thick before on my own strut towers. Even if it isn't scale it isn't any special "reinforcement ring." It could be a shim someone added to gain ride height or correct the alignment. My car had no such thing.

 

[Intuit]

That's fine if you don't trust me (I'm no expert,) but do trust the body shop personnel, who also disagrees with your assessment. We were both direct observers. They actually worked on the vehicle. This was no "scale." The passenger side strut mount was completely disintegrated, while the driver side was intact. If it were scale as you claim, not only would the body shop personnel have pointed that out, but the two sides would've been different as the original strut mounts were. They were welded (tell-tale "waves") around the parameter. (are shims welded ?) Unless Ford did it, there were no "ride height" or other special modifications done to the vehicle.

 

[madmatt2024]

It still sounds strange to me though. Nobody on this forum has ever mentioned such a piece in the 6 years I have been a member and my own car had no such piece when I took my struts out.