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Outer rocker showing "rust"

Lukens

Jedi Warrior
Offline
Starting to see a few pimples/blisters on the outer rocker of my TR3. First impulse is to sand down to bare metal. prime, and respray.
Second thoughts is that this rust is coming from within the rocker. Don't want to get into cutting and welding, or bondo. Any ideas as to how to "deter" this problem?
Lukens

Update: I see there are plugged "drains" on the bottom side of rocker. Do you think spray a rust converter inside the cavity would prevent further rusting?
 
Hi Lukens - others with more expertise will give more details, but I'd think if there are plugged "drains", then the rocker probably filled with water which is causing rust through from the inside.

Spraying a converter would deter - but not prevent - further rusting, as it's probably already penetrated from inside to outside. I think a new rocker is in your future.

Tom M.
 
Thanks Tom,
When I said plugged, I meant that there are drain holes with rubber plugs in them. I'll open them up and see what I find.
 
Do you have any idea of the history of the car?

If it was restored by someone else they may not have primed inside the rocker panels.

David
 
If the rust is from the inside then it is probably too late to save the rocker panels. A quick diagnostic is just try to feel the strength of the metal with your thumb. If it is still rigid then it might be worthwhile to try the rust converter then get some paint in there.
 
Ready to do a little "exploring"
IMG_4765.jpg
 
First some good news, at least the best I can come up with, the outer rocker panel replacement is a straight forward project and not disastrously expensive. Not so good is what appears to be a bubble in the dogleg behind the rocker, although that can be patched at the same time. These are two of the favorite rust areas on these cars. Both could be satisfactorily repaired with POR15and bondo but although cheaper, that would be far less lasting and I would not recommend it. Finally, go over the rest of the car from underneath to confirm that the rust is confined the the rocker. Pay close attention to the inner rockers. If there is more, it will probably be cheaper to get it all addressed at one time.
Tom
 
The car was lasted painted in 2002. Other than this rocker, no rust. I pulled both plugs from underneath, and stuck a 12" flexible air hose in the forward hole. I was surprised when about a half cup of powdered rust blew out the rear hole (along with a zillion Florida Crazy ants). Then I chucked an 18" flexible spring in my drill and ran it in both holes. I repeated this until no dust blew out either hole. I then attached a plastic tube to a spray can of rust converter and shot about a half can into the cavity.
When I sanded the blisters down to bare metal and I was pleased to find only "microscopic" pin holes. So small that I brushed a little super glue over them and they disappeared. Sanded again, primed with self etching primer, and I waiting for a rattle can of "Ford Thunderbird Inspiration Yellow" to be delivered.
The rocker is solid, no weakness, so I believe I'm good for several years anyway.
While I was at it, I decided to check the other side rocker. Oddly enough both plugs were absent and I got nothing from it with the compressed air. Now I'm wondering if it isn't better to leave these "drains" open. ?????
Lukens
 
Sounds good to me. I will admit that I have little experience with rust converters, encapsulators and the like but from what you've done, it may be a decent alternative to replacement. Time will tell.
As for the plugs, I think they were put in at the factory. Mine had them when I bought it used in 1964 but the PO might have put them in. They were certainly necessary here in New England during the winter but you could probably make a case for leaving the out in Florida.
Tom
 
Even pin holes would be worrisome but if you felt no weakness then you probably are good for maybe a couple more years with the rust converter inside. Could be worth a try anyway.
 
Good luck!
 
One thing I learned is that besides the drain holes, the actual drainage channels can fill with dirt. Then, when it rains or the car gets wet, the water doesn't pass -- it just mixes with the dirt and starts to eat away at the metal. While I didn't have this on my '69 Sprite, I did have a huge issue with my '53 Plymouth. It was a Nevada car, but apparently picked up a ton of sand in the drainage channels. The front of both wheel arches were rusted out and the left side rocker ahead of the arch had rotted out. I had no choice but to repair.
 
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