Radiator drain plug

[robbo21]

I'm hoping someone can help. I stripped the threads of my radiator drain plug while draining. I have managed to get my old one out and got a replacement but having a lot of difficulty getting the new one back in. Have tried lub on the o ring seal but no joy. Is there a knack or do I need to use more force to get it back in. don't want to damage the new one. Had the vernier callipers on it seem to be the same size but is so tight to replace.
Thanks for any advice.

 

[brandwooddixon]

I'll take your word for it that they're both the same size (the right one looks bigger in the photograph).
It looks as if the plug needs correct orientation before it can be inserted and then twisted 90 degrees. I suspect that applying pressure (to push it in) may work against you.
As it appears to have a rubber O-ring, I'd lightly smear it with silicone based grease only.
Although damaged maybe practice with the old one first.

 

[AlanGunn]

+1 on correct orientation well it looks that way to me but never taken one out.

 

[DREAMER NO2]

Yea i was told to leave them drain plugs alone , and not to ever remove them ,Just pull the bottom hose off .You need to clean the thread up in in the bottom of the radiator Or deleat it,, get some jb weld and give it the works . You can work round it in the future , just pull bottom hose off .

 

[robbo21]

Thanks for the info. Managed to get it in in the end. Gave it a slight rub over with some wet and dry and added some lub. Tight fit must have been a bit of newness!! .As its an old car hopefully wont have to tamper with the coolant or drain plug again .HOPEFULLY.