The spark plug hole stripped out on my 400ex the other day. What is the best way to fix it cheaply?
Blow Out
- Thread starter 06twostroker
- Start date
How exactly did it strip out? Sounds like you were running the engine and the spark plug blew out of the hole?
If the threads are just damaged and not completely stripped out, a spark plug thread chaser will often straighten them out without having to disassemble the engine. Its worth a try.
If the plug was blown clean out of the head and took most of the threads with it, your best bet will probably be a spark plug helicoil. While you can usually install a helicoil in a head without having to remove it from the engine, its almost impossible to keep metal shavings out of the cylinder while drilling and re-tapping the spark plug hole for the thread insert. SO, if it was my bike, Id remove the head and repair it on the bench. That's your call, but if you pull the head, you can also inspect the cylinder, piston, valves, guides, followers, seats, cam, and cam chain for wear.
If the threads are just damaged and not completely stripped out, a spark plug thread chaser will often straighten them out without having to disassemble the engine. Its worth a try.
If the plug was blown clean out of the head and took most of the threads with it, your best bet will probably be a spark plug helicoil. While you can usually install a helicoil in a head without having to remove it from the engine, its almost impossible to keep metal shavings out of the cylinder while drilling and re-tapping the spark plug hole for the thread insert. SO, if it was my bike, Id remove the head and repair it on the bench. That's your call, but if you pull the head, you can also inspect the cylinder, piston, valves, guides, followers, seats, cam, and cam chain for wear.
Perma-Plug M14 X 1.25 Spark Plug Hole Repair Kit : Amazon.com : Automotive
dunno know if it's the right size or not but that should work if you completely stripped the threads out. i would pull the head to do it.
dunno know if it's the right size or not but that should work if you completely stripped the threads out. i would pull the head to do it.
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All good suggestions!
I have used helicoil for one of my exhaust studs and also for drain plug repair worked great. Timeserts are a better version, and twice as expensive However I've had great luck with helicoils!
However those permacoils scot posted no drilling required? Sounds easier and they look like a timesert.
I have used helicoil for one of my exhaust studs and also for drain plug repair worked great. Timeserts are a better version, and twice as expensive However I've had great luck with helicoils!
However those permacoils scot posted no drilling required? Sounds easier and they look like a timesert.
Thanks guys. I was looking at timesert but they are very expensive. Im not sure exactly what happened I left it at my buddies house and he said he went to start it and it made a pop and had no compression which was the plug. I already have the head off to do the job right but I dont know to use heliciol, timesert or perma plug? Its 12mm 1.25 18mm long. Perma plug looks very appealing but can I get one in 12mm?
