The other night my bus starting making an awful knocking sound. At first I thought I had thrown a rod but after further inspection the number three cylinder had just blown out my spark plug. When I tried to install a new plug I noticed that the threads where worn out. I couldn't get the plug to catch. Is there anything I can do without dropping the motor and having it machined? Maybe something I can do in the short term?

Thanks,

K-D plug repair bushing.  Kit should come with a 2 stage tap and serveral   size bushings . I have had that repair kit for years and they work well and can be done in car. Tap the hole , put the bushing on the plug and screw it in . Thats it.