I thought if I ran a bead of silicone caulk along the seam and ran a finger along it to squeeze it in, that might be a cure. Obviously not. Suggestions?
You'll have to take it apart to fix it now. (Just to remove the silicone.) Solder won't stick anywhere that's had silicone smeared on it. Especially if it's "squeezed" into the seam. It's hard enough cleaning the surface of antifreeze but cured caulk will need mechanical removal.
Steve is that the radiator that was recored on your 15?
You will have to remove rear of top tank,and clean it to resolder. The worst part is putting tank back,back on. The inlet draws heat away and that is a fun job. Almost all of solder on a brass radiator goes on from inside. I built the radiator on my speedster and it takes time. Good luck.
Yes, it is the 15. I'm afraid Ken is right about having to scrape/sand/wire brush the silicone out.
(Message edited by steve_jelf_parkerfield_ks on July 27, 2015)
If you have it professionally done, don't let them "polish it " for you. They may used a wire wheel on a drill. If they do, you will never sand out all the wire brush scratches. I know!
Something stronger? Epoxy maybe.
Looks like a job for MBRT!!! Where is H J when we need him??
J B Weld also works on radiators but you would need to remove the silicon...Paul
If you do try to use J-B weld get a syringe that you can get at hobby shops. You can find them online also. The small ones that bake shops use for cakes would work also. The least you put on it to begin with the better looking the job will be.
In warm weather J-B weld will flow fairly easy. Mix up the J-B weld and put it in the syringe. Slowly squeeze it out the same way as you would if you were using caulking gun. With a little practice you can get a small smooth seam with a syringe with J-B weld. You could press it in the seam also and keep it really smooth with out a lot of smearing . J-B weld cures fairly slow so you would have time to work with it.
I would at least try go clean out the silicone the best that I could and try to seal it with some type of epoxy before You spend a bunch more money.
Just wondering if you could laquer thinner or something similar to remove the silicone.
Good luck with whatever you do.
Two pieces of wax paper is a great way to apply JB weld or any epoxy in thin places like this as well.
You sandwich a few drops in between the waxy part being sure to leave plenty of paper around the edges then carefully slip the paper under the crack and then rub the epoxy deep under the crack. Gets it under there and leaves no mess around the edges
It needs to be properly cleaned & soldered.
I can only mention something that a plumber recently did at my house.
He wanted to get the surface mounted vessel sink off of the stone counter. He stood there with Citrus Go Jo on a rag and kept wiping the seam while he talked. After a while that was no more than 10 minutes it did let go and pulled off fairly clean.
He then used mineral spirits to get rid of any residue for when it went back on.
Don't know how that would work on brass...but offer it to foster others ideas and comments.
You can take the back of the top tank off and then bead blast inside the top tank (mask off the core with foil tape first). Then vacuum out any blasting grit, flux and solder.
I've never been able to get rid of the silicone "virus" with anything but lacquer thinner or acetone followed by ammonia soap and good rinse. I don't even allow sprays containing silicone in or around my shop. The atomized droplets can travel hundreds of feet and contaminate surfaces for years. It's a death sentence for parts that will later be plated, painted, glued or joined by solder. Even RTV products are handled cautiously. And it can be transmitted all over through tools and finger prints. That's why I call it a virus.
For a grease-pit shop, it probably makes no difference but for a paint/body shop, it's a terminal infection.
Forgot to mention:
If you really want to know if a surface is clean, do the "water-break test". Use a spray bottle filled with clean water (distilled preferred) and wet the surface. If the water stays together and/or flows off in a sheet, it's clean. If the water beads-up or pools like Swiss Cheese, it's not fit for coating.
The radiator should be removed up ended and cleaned with a Dremel wheel in the seam. Heat the area under the melting point of the solder and brush with a Teflon brush to remove any contaminants. Retouch with the Dremel wheel and apply soldering flux to the cleaned surface immediately. Fabricate a stick the same shape as the finished seam or close thereto and with an assistant to spread the solder when it is at a solid solution. A small amount of flux on the stick helps. This can be trickey just enough heat to require the solder to flow in the seam and to be spread. Too much heat and disaster. However it is always repairable regardless of the out come.