Sealing Radiator Hose Connections

[mike brady]

I cannot seem to get the 2" lower radiator hose on my Cord tight enough, to stop seeping, with the correct clamps.  The fittings on both the water pump and radiator are smooth (not pitted) and painted.  I would rather not use stainless gear clamps, if I can avoid to.   The hose is a new piece of Gates Green Stripe.  I would appreciate any suggestions which would stop the seepage.  Thanks

[PFitz]

I've always used Permatex Aviation "Form-A-Gasket" to seal radiator and heater hose ends to their connector.  Lightly and evenly  coat the dry and cleaned connector, plus about an inch of inside the hose end.

 

Let it setup for a couple of hours to allow most of the solvent to blow off, then slide the hose on and clamp.  Never had a leak in 50 years of using the Permatex.

 

Paul 

[Akstraw]

I had a similar problem once, not on a Cord, though.  I finally put on one of those conventional gear clamps, as well as permatex, tightened it up and drove the car.  I re-tightened it when the engine was hot, and ran the car again several times over a period of a week or so.  Seepage was gone.  I then switched back to the original style clamp when cold.   It has not seeped since.  I think the old two-wire clamp did not apply as much force all the way around the circumference as do the modern clamps.  No way to prove it, though, just my suspicion.  I also think tightening hot helped the rubber conform to the metal outlets.  One downside is that if you tighten the heck out of the ss gear clamp, it will emboss pattern marks onto the hose.

[AHa]

I thought of using water pump packing grease smeared onto the connection. Don't know if it would work but I thot it reasonable.

[Grimy]

My standard procedure when replacing hoses is to use modern gear clamps initially, with the ultimate (correct) 2-wire clamps at the center of each hose, tightened just enough to keep them from rolling around.  After 10-20 heating and cooling cycles, when the hose has heat-bonded (to some degree) to the necks, open (split) the gear clamps and remove them, one at a time, and slide the 2-wire clamps into the positions previously occupied by the gear clamps.  The reason for pre-installation of the 2-wire clamps is that I find it nearly impossible to line up the screw with the nut after the 2-wire clamp has been bent while open.  Sorry for the lengthy rationale...  The gear clamps do a much better job of establishing the seal on a new hose, but even they usually need a retightening after a few heat/cool cycles.  Especially on corroded water pump castings, there is a need for some sealant.  For a severely-corroded neck, Indian Head gasket shellac will do the job but you must cut the hose off, with some difficulty, at replacement time.

[ArticiferTom]

I had same problem . Coated metal with blue RTV let set up in pits . Added more with hose and clamp with two wire . Worked first time all four connections .