HELP - Stripped Threads

[ridders]

After spending the last few months trying to get the van on the road I have now come across yet another of the previous owners bodges. Decided to give the van an oil change tonight ready for our first camping trip tomorrow (Saturday) only to discover the oil drain plug was only just finger tight. On removal found a load of orange sealant and thought the worse. Sure enough the threads have stripped out of the engine casing. Tried winding endless ptfe tape onto the drain plug but just wont nip up. I know i could have a go over filling up the threads with silicon and fit the plug and leave overnight but just wouldn't trust the van on a long run full of the family.

My thinking is helecoil or drill and tap out the hole to the next size. Not really tooled up for this job so could do with someone local and with an hours time on their hands to fix it??

I'm getting close to putting this problem right and selling the thing as its just one problem afetr another... brakes, wheels, steering bushes, water jacket seals, water pump, thermostat, gearbox and now this. All of these were proper problems and not just done to improve the looks or anything.

By the way the van is a 1984 1.9cc watercooled hightop

[getunder]

As a temporary emergency measure I had this problem on another old car. I found a similar sized bolt with a slightly different thread (AF,BSF, I dunno.) which fitted quite snugly with a bit of welly,but not too much. This temporary repair lasted about 5 years until it was scrapped. I would issue a strong disclaimer with this advice - but it worked for me,once. An old Desert Rat trick

[Rozzo]

i agree, since the threads are alloy a steel bolt will probably bite in.
long term as you said drill and tap next size up. i believe this is a common problem as are all the others you mentioned but rest assured that now you've cured them they shouldn't bother you again for a few years

[getunder]

Did the bolt have a washer on it ? If so, remove the washer and replace it with sealant. That extra mm or so of thread might just bite enough to firm up for now. Another straw to clutch at Two part Leak Fix from a tube? But you probably would need to get threads oil free which would be difficult on the sump.Another straw maybe. ?I used it once to repair a leaking copper carb. float and it lasted for three weeks. And it was immersed in petrol all the time.

[AngeloEvs]

You must have the patience of a saint, IIRC someone found a company that fixed it (helicoiled) at their home - I might have got that wrong but might be worth a search.

[clartsonly]

I think you may find a lot of t25s have cut up spark plugs as their drain plugs, I know mine does.

[getunder]

If you used a complete spark plug I can see it confusing an apprentice mechanic. He would be looking around for the camera