MTFCA Forum

Does anyone have a solution to leaky radiator hose connections? I’ve tightened the clamps but still leaks.

Seems like a non setting sealant might be in order?

i use Permatex no 2 gasket goo on the hoses. It does not set hard. On rust pitted outlets it pays to use worm drive hose clips as these can be tightened much more to make the hoses conform to any irregularities in the fittings. Once they have been on for a while, they can be removed and the usual old style clamps can be substituted. The old style clamps do not seal as well, especially on pitted fittings. Tightening them often makes matters worse, as the hoses can be pinched at the clamp joints, making a leak more than likely.

Hope this helps.
Allan from down under.

The inlet and outlet castings on my '26 were pitted and difficult to seal. Rather than using sealants, I used JB Weld to fill and smooth the pits in the rings that hold hoses. Once they were smooth and rounded, I had no problems using reproduction clamps.

I use clear RTV on hose connections. Seals well. When it is time to remove just twist/rotate the hose and it comes off easily.

Its a great idea to use JB-Weld to fix the pits as Mark suggested...
Here are some previous discussions and solutions
By John F. Regan on Sunday, June 10, 2018 - 11:42 am: http://www.mtfca.com/discus/messages/82 ... 1528647321
There really is no need to put on RTV as a sealant when replacing hoses and clamping them for a time using modern band clamps. Only AFTER the motor has been brought to full operating temperature for some run time hours is it then OK to release the band clamp and install the original looking hose clamps. I have done that on many cars including show cars and I have never had one leak later. I have also never been able to use an original clamp and NOT have it leak. The inner rubber on the red T hoses sticks very tight once the engine heats up and the modern band clamp is applying clamping pressure. There is no real "dead line" with regard to swapping the modern to original but don't do it too soon before the engine has some hours on it via a few tours.
Discussion on Reproduction Hose Clamps issues http://www.mtfca.com/discus/messages/82 ... 1518040392

You must have a good raised ridge to put the clamp behind

Rough pits: What Mark said. Fill and smooth.

I use the original style clamps but I replace the round head screws with fillister heads to give the screwdriver a better grip. Instead of sealant I slather on some grease so it will be easy to remove the hose if I have to. BUT if I have to remove the radiator I leave the hoses attached and unbolt the inlet and outlet from the block and head.

Steve's photo shows the problem using original clamps can cause. Notice the 'hill' pinched in the hose between the clamp lugs. If that causes a leak, applying more tension to stop the leak makes the 'hill' higher and the problem worse. That little sliding strip which is supposed to keep the 'hill' in check is nowhere near as effective as a worm drive clamp. I'm with John on this one. Use modern claps first, and replace them with 'correct' ones once the hoses have settled in.

Allan from down under.

Check to be sure the leak is really from the hose connection. I've chased a stubborn leak in the past, only to discover it started from higher up, on the radiator tank. The coolant slowly travelled down and settled in the seam at the top of the hose, making the leak appear to begin there.