What is the best way to get rubber radiator hoses to seal on plastic tanks. The rad is aluminum and the sides are plastic. Thank you in advance for any responses.

 

well making sure you have the right hose for your application helps. a good hose clamp also helps as well. the stock clamps dont work all to well. how old are the hoses?

 

New hoses I put on a rebuilt radiator. Its like the rubber and plastic won't bond and I continually have leaks. I read somewhere this afternoon touse hair spray on intercooler boots wonder if it would work in this case? New clamps were also put on.

 

I"ve heard double hose clamping them works the best. Either that and instead of using a screwdriver, get a 5/16 socket and crank them down. Now that you mention it, one of our work trucks leaks right at the upper hose where it meets the radiator, 1yr old radiator and 1 year old hose, wonder whats going on? I'll have to try the double clamping method.

 

I'll have to try the double clamp. I've used the socket instead of a screw driver but have never really cranked on it with the tanks being plastic. That makes me think that maybe that is the problem, it is cracked already!

 

I was always afraid of that too. I put on an electric fan on my truck, hence i needed the thermostat probe that goes between the upper radiator hose and the radiator, and there's some rubber wedges that you put in between. It leaked, then i tightened it, and it leaked some more, then i cranked the dang thing down until the wrentch would hardly turn anymore. Then i put another hose clamp on it to be sure and it hasnt leaked since! Same with upper hose that goes into the block, i got one of those chrome water necks, henc its shinny and slippery, and i put the hose on, thought i had it fairly tight, it was leaking, and i could pull the whole hose right off. So again i cranked it down with the socket. until it got tight. I think that a plastic circle like that can be pretty weak when your putting 2 opposite forces on each side of it, like stepping on it, but when your putting a clamp around it its putting forces on each point around the circle and they kind of cancel each other out, so its pretty strong in that respect.
Try getting some schedule 20 PVC and putting a clamp around that to see what i'm talking about. That way you can kind of gauge how much pressure you can put on that radiator neck before you crush it.

Plus, look at it like this, if its a new hose, and the connection is still leaking, then either the tank is cracked, or the clamp isnt tight enough. So if you tighten it down and it breaks, it needed to be replaced anyway because it was leaky and basically worthless. If you tighten it down and it stops leaking, you just solved your problem. Now if you crank it down as hard as you can get it, and it still leaks, i guess i dont know what to tell you then, lol. Good luck, -Peter