Leaking Bottle

Thanks IAMICHABOD. I will try it.
This tank I bought 16 months ago cost $200 PLUS fast shipping from Oregon another $100... so, I'll try anything at this point.

I would opt for JB Weld I have used it for similar problems with great success.

The tank is only 1 year old and I don't believe it is cracked. In fact the reason I reseated the fitting was because it was too loose. Since the tape did not work, I thought there may be a gasket sealant. Maybe JB Weld or something I could use instead of tape.

Yes, replace the surge bottle, the plastic probably has a lot of minor cracks in it from the heat.

On my 2005 Fleetwood Excursion 39S with a Cat C7, the surge tank that sits on the top right corner of the of the radiator went in Billings Montanna last year. Luckily it was across the freeway from a Freightliner dealer. They had them in stock because a lot of them went out. They said the original plastic wasn't a good quality for the engine and water heat it receives all of the time. They changed it out and I went on my way.

Bill

The tank is probably cracked at the threads. Buy a new tank