Engine trouble...

Well, I was on my way to work and I had the #2 cylinder spark plug blew out of the cylinder on my 1982 XJ650....Just wondering if anyone has had a similar situation happen before I start tearing into it tomorrow.

Thanks for any help!!

 

Noffy, did blow out & strip the threads or did it blow out because it wasn't in tight enough? I would look in the plug hole & see if the top of the piston is holed. Otherwise, I believe the problem was due to not being tight enough & it backed out of the threads. Just a thought.
Gregg

 

If the plug hole is stripped and no threads left you can heli coil it while still on the bike. The trick is not to let any metal shavings get into the cylinder while you are tapping the new threads for the heli coil. Apply grease to the tap so the shavings stick to the tap. You'll back it out several times and clean off and put new grease on but its alot better than pulling the head. Install the new heli coil and away you go. The newer Ford Triton engines have problems blowint the plugs out. The fix is the same. Install heli coils and your good for another 100K. Check with a machine shop or a real good auto parts store like NAPA. They will get you what you need.
Good Luck and let us know.

 

Well, I had to limp into work on three cylinders but after I was here, I put the spark plug back in and started it up again, but the plug just shot out again. I can't tell if the threads from the spark plug went, or the threads inside the head. Figure I'll get a new spark plug tomorrow and try again. I am almost positive that it was in there tight...but who knows...Any ideas on what would cause this if the plug was in there tight?

"greggvickrey" what does it mean if the top of the piston is holed? I'll check it out and let you know.

Thanks for the help...

If I need to retap the spark plug boss, are we able to get stuff for this at a Napa?

 

He's asking if the piston has a hole burned through it. I would doubt it because you have enough compression to blow the plug out. you may have a couple of threads left but when the head heats up it expands enough to let the plug pop out. Go to NAPA and see if they have a 14mm spark plug heli coil kit. (Long Shank)

 

Alright, MN, thanks for the advice.. That was a good explanation

 

Before you tap the head. make absolutely sure that the valves are closed!! No fun replacing a valve because you tapped it.. Did that on my 550

 

Well, thanks for the help guys, I heli-coiled it right in the parking lot at my nearest Napa...Rode it 15 miles home and it rode just fine...now I think I'm going to finally get around to cleanig out my carbs completely.

 

Noffy, glad you got her fixed. Sorry I didn't explain the holed piston, sometimes we assume everyone knows what we are talking about. Enjoy you ride.
Gregg