Blown spark plug.

[daveschile]

I've got about 200 miles on my '82 that I bought a couple months ago.  Just starting to get confident with her, pushing her up to 80 mph cruising, and I blow the right side spark plug.  Nails my ankle, but stays in the wire.  Spent a few minutes on the center divide of I-405 in busy Sothern California traffic.  Good times.

I'm gonna try the Helicoil fix with the head still on the bike.  Any suggestions or heckles?

[montmil]

Heavy grease on the drill and the tap to collect as much swarf as possible. Small magnetic pick-up to probe the combustion chamber for additional junk. Light 'er up and blow out any leftovers. That's about all you can do.

I did this on a late 60's Bonneville and the engine ran forever. Luck to you.

[daveschile]

Thank you, Monte.  I am also thinking on running the shop-vac as I cut and suctioning the port afterwards.  

David

[nhmaf]

A shop vac with some modified nozzle to really get the suction in there might not be a bad idea.  With the alloy of the head, I am doubtful that a magnet will pick up everything.    USe plenty of tacky grease and go slow!
Good luck!

[livingdeadhead]

sorry wrong! the absolute BEST way to remove all swarf is to

1-stuff some tights into the cylinder (panty hose)
2-then push grease into the cylinder
3-helicoil
4-pull the nylons out by the time you've got the lot out you'll have pulled all the crap out (use a bent coat hanger)
5-job done

or! to do a proper job take the head off and time sert it !

[montmil]

Oh, I can picture it all now in my head...

Wifey: Darling, Whose panty hose are these and how did that get all that nasty grease on them?

   LDH: Oh that, Luv. Uh, I was just fettling the old Beemer a wee bit.

Wifey: Not my size! Now, where be me skillet? Your arse in mine...

[Luca]

If you get the cylinder going on a compression or power stroke you will keep the valves seated and the seats free from any stray swarf.  Getting the piston as close to TDC as you can while still leaving room for the tap will minimize the chamber volume and probably make cleanup easier.

+1 on the nylons.  After you remove them, get an air gun with a long wand and stick it down into the cylinder as far as you can and let it rip, moving it around the cylinder.  With the valves seated the only way for things to leave is through the plug hole.

[montmil]

Wear safety googles when air blasting metal bits. Don't need any problems bigger than the stripped threads.

[daveschile]

Thanks for the ideas.  I had no spare panty hose, but I still like the idea.  Anyway, all went fine.  She's back on the road, running great.

In finishing that job, I noticed a valve cover leak on the same side that seems to be spitting exhaust gas.  I wonder if the issues could be related?

[livingdeadhead]

reason behind the nylons is you can get all of it out and it doest leave bits behind doesn't come apart and if you twist it on the way out it cleans the crap out of the threads , done it loads of times when i had the shop.
   you mean the actual valve cover is pressurised enough to blow exhaust gasses ? sure its not the head/barrel joint?

[Barry]

In finishing that job, I noticed a valve cover leak on the same side that seems to be spitting exhaust gas.I wonder if the issues could be related?  

Crank case compression would pressurise the valve covers and could sound like an exhaust leak.  It wouldn't be related to the spark plug threads but you should fix it as besides the noise it will be affecting the engine breather operation and maybe oil consumption.

[daveschile]

Yeah, it feels like its coming from the valve cover.  Granted, it is near the fin-nut.  But it really feels like the valve cover gasket.  

[nhmaf]

If it seems like exhaust gas is puffing out the valve cover, then it would seem to be a very worn valve guide(s) on that cylinder, and/or valves not seating tight.   Maybe it is the head gasket?      Or, sometimes one will get some steam escaping from the notch area of the valve cover directly under the spark plug lead due to moisture accumulating in there, and then getting evaporated out as the engine heats up - most common if you leave the bike out after a rainstorm or wash it with a hose.

[flybot]

Im trying to understand this "stuffing panty hose into the cylinder" thing, in case I ever need to use it. First of all- WTH?   Then, do you just stuff a whole leg in there, add grease, do the thread repair, then try and find a piece and pull it out with needle nose pliers? What if you cant grab any of it? And is the idea that it will pick up the swarf (another new term for me) with its nitting and grease?

I love little tricks like this. Unless its just a sick joke. Then Ive been had...

[livingdeadhead]

i use some surgical forceps , the nylons compress really well , you can even rub a little grease into 'em too , the more you put in the cleaner the thread will be when its all out , i was shown using just cloth but that sheds and rips i've done it and recommend it if youre unwilling to take off the head, and on a bmw flat twin its much easier than a jap four!