F100 300-I6 1980
Drain plug---(which is plastic) in radiator has slight leak,can not tighten anymore,anybody got any ideas on stopping this leak?The leak is not severe but annoying, Thanks for any suggestions.

 

Does it have an o-ring? Try putting an o-ring on it, unless it's leaking from some other source, so why don't you replace it with a metal one? Just get the drain **** and match it with one at one of the Auto Parts places.

 

Yes it has o-ring maybe I need to replace that ,does the drain **** just screw all the way out?

 

I'm not sure if it screws all the way out, but you won't need it to, just stretch the o-ring around the plug and then match it up at an auto parts store. They should sell various o-rings individually, and they should sell them in packs of various sizes.

good luck

 

If it's a plastic plug, I would simply replace it, making sure you have the o-ring as suggested by 99EXPY. what probably has occured over time, is the threads are not as "deep" which allows seepage of coolant past them. Especially, if you are only experiencing a noticeable "drip spot" as compared to a good sized leak. Just my 2 cents.
This would be a good time to replace your radiator cap with a Motorcraft cap. With an older radiator, drop your pound rating a bit. For example if you are running a 15LB.-16lb. radiaitor cap, use a 13lb. cap (Motorcraft makes an excellent cap at 13lbs. Says RS-62 in the copper part area) It costs about $8 at the Ford Parts Dept. and is worth every penny. Plus it gives your radiator a bit of relief from the extreme pressure it's under.