Will Boston Valves Hold Air Using the Cap Alone?

Hello,
I have a Sevylor T68 dinghy. It has been a lot of fun, but this year it has a slow leak. I have tried soapy water, but no luck there. What I did discover is that two of the Boston valves leak, i.e. they don't work in just one direction anymore. A very slow, but steady, amount of air leaks back out through them when the dink is inflated.
I thought I could just make do by tightening the valve cap down very well. When I do this, and then apply soapy water to the cap, I don't see any air leak. But then, the leak may be so slow as not to see it this way.
So, am I wrong in thinking that the cap of the Boston valve will hold the air in? I looked inside the cap, and there isn't any sort of oring or gasket in there to make a seal. Should there be?
Thanks for your help.

Re: Will Boston Valves Hold Air Using the Cap Alone?

I dont have a sevylor (well, I do but its a HUI 400, no boston valves) but my Intex Mariner 4 has them and I dont actually have to screw the caps on. I do because....well.....just because, maybe to keep water out and prevent any premature damage/weathering issues. But even without the caps the air stays tight in the boat. Maybe its the welding/glue around the valves? Good Luck!

Re: Will Boston Valves Hold Air Using the Cap Alone?

mrdrh99 said:

I dont have a sevylor (well, I do but its a HUI 400, no boston valves) but my Intex Mariner 4 has them and I dont actually have to screw the caps on. I do because....well.....just because, maybe to keep water out and prevent any premature damage/weathering issues. But even without the caps the air stays tight in the boat. Maybe its the welding/glue around the valves? Good Luck!

Click to expand...

I appreciate your reply, but my question is not whether I need the caps. My question is whether the caps will hold air in the dink if the Boston valve inside has a slow leak. Not a leak around the valve, but inside the valve itself. There is no doubt that air leaks out of the Boston valves I have. I want to know if the caps will keep the dink inflated in spite of this.

Re: Will Boston Valves Hold Air Using the Cap Alone?

If you go to an hvac supplier store buy a bottle of liquid snoop. Is about 10 bucks and it can find any leak you have. 30 times more sensitive than regular soap bubbles. I use it to freon leaks that are ounces a year loss not pounds.