Bill Ball

My 89 has developed the proverbial passenger side radiator sidetank seal leak, as decibed in Nichols Tips. The end tank with integrated seal is available. Any advice on how to remove and recrimp the end tank?

SharkSkin

Carefully?

I think some radiator shops have the right tools to uncrimp/crimp those properly. Whoever did the side tank for my PO apparently didn't have those tools... I think it's important that the right tools be used, since the tabs won't take much flexing around before they break.

Jim bailey - 928 International

The key to successfully changing a side tank is limiting the stress and bending of the aluminum tabs. Most important is that you use some form of clamps (pipe clamps) to push the new tank and new seal all the way into the recess of the core. That way you are bending the tabs back down only once to HOLD the tank in place and are NOT trying to seat the tank and seal by bending down the tabs. The tabs are a brittle aluminum and too much bending causes them to break.

Garth S

Bill,
Did this once on a BMW rad - at a rad shop. The end tank was compressed against its seal prior to opening the tabs: this minimizes stress on these delicate critters. The replacement tank and seal were likewise compressed to permit maximum tightness on the tabs when tapped back into place.There often is no second chance, as the tabs fatigue and snap.
Were I to do this at home, lengths of wood over the outboard ends of the tanks to spread the clamping force of 3-4 wood panel glue-up clamps would be the approach .... oh, and crossed fingers ...

Bill51sdr

Bill, I just went through this myself and would strongly suggest letting a good radiator shop do it for you. They have the correct tools and jigs, I'm quite happy with how mine turned out... no leaks or broken tabs .

Bill Ball

OK, good advice all. I will try to find a local shop that seems to understand the compress, uncrimp, remove, insert, compress, crimp routine. I would have mooched this on my own, not knowing about the compression step. Needs to get added to the Nichol's or 928OC tips.

Sab

I had this done recently and checked with several rad shops. Some said that it wouldn't work, some said it won't last and then one said he'd been doing it for 15 years. He charged me $80 and had it done in four hours (I only brought the radiator). Works perfect since about four month.

Ispeed

I just had a good radiator shop re-core my '87 5 speed radiator and use new end tanks. My core was leaking as well as a leak from one of the tank seals. There is a Behr replacement core out there for the 928. The new core is a more modern efficient design and should cool 30-40% better. They had the correct tool for recrimping tabs and told me that when it is leaking from the end tank seal, you only need a new seal and not the tanks. Labor to only change end tanks is $30.
Good shop; A and I Radiator in Attleboro, MA (508)695-6057

Cost for a new core + labor was $460, turn around time a couple days. They were good.

docmirror

I have been looking into setting up a jig to do this very job on the end tanks. What I found is that there are shops that have done them in the past, and now know the procedure to do it successfully, and other shops that just hack at it, and pray it doesn't come back. I've found a good shop in Ft Worth Tx that can do the job, with the right compression jig. I plan on taking them a radiator next week after I get a new seal for the end tank.

The compression jig looks like a long slot cut in a metal frame. The rad core slides into the slot, with the flange sticking up, and then the seal and end tank are set on the core. The slot supports the base of the tabs that are folded, not the bottom of the other end tank! this is important to aviod flexing the plates at the end of the core where the tubes are supported. Once the pressure is applied evenly on the tank, only then can the tabs be crimped in with a large tool that looks like a goofy vice grip.

Since the process is pretty complex, I've put my jig on hold, pending the outcome of the work I see from this shop. While I was in there with a Ferrari radiator, they had several of the tounge and groove style rads lying around. I guess they have a reputation of being able to fix them, so I'll give it a try. When it's done, I'll let you know. Sonds like there are various other shops around tha thave similar types of experience.

Doc 90GT in resto

Bill Ball

Took the radiator out and over to a local shop that said they work on Behrs with side tanks. They pressure tested and found the tank was cracked near the top, so it wasn't the seal. Can't see the crack, but they showed me the pressure test and it is cracked. Ordered the tank&seal today. Just for the heck of it I will throw in some BarsLeak and see what it does.

Bill51sdr

Bill, if you haven't already, I'd skip the Bar's Leak. Ron V had/has EXACTLY the same problem (as did I), and the Bar's leak only worked temporarily and then clogged his radiator core so badly that he had overheating problems on our way up to Tahoe on 395. His radiator resumed leaking on our way home Sunday. You will also have the added pleasure of flushing that crap out of your cooling system once you remove the radiator, BTDT. I'd just park it 'til your ready to do the tanks.

Bill Ball

OK, no BarsLeak!

IcemanG17

Bill
My neighbor has a 97 BMW M3...with a very similar radiator....his completely blew out the side tank....while he was driving!

So will need to replace the whole main tank? Might as well get the Devek radiator with the increased cooling to match your new fan assembly!
Brian

SharkSkin

Yeah, my old rad had the lower cores clogged with Alumiseal or Bars Leak.... Good call avoiding it.

T_MaX

Bill, YOU CAN DO IT!

You can get the clamps at Home Dept.!