Stripping the spark plug hole?

[Sjorge450R]

What would happen if you stripped the spark plug hole, when putting the spark plug in. I never did this, an i dont think that i would but i was just wondering if it would be fixable.

[Rip_Tear]

Umm, you could replace the head. I don't know if any "easy" (heli coil etc) would work, you could have it drilled out and a plug welded in there and have it tapped. I'm not sure what else would work. Safest would be the new head.

[Sjorge450R]

yeah i'm always careful when putting the plug in just because of this reason and i was just wondering how you could fix it if it did happen.

[fwm416ex]

Check these out:
http://www.timesert.com/html/mtrcsert.html

[prepracing]

Originally posted by Rip_Tear
Umm, you could replace the head. I don't know if any "easy" (heli coil etc) would work, you could have it drilled out and a plug welded in there and have it tapped. I'm not sure what else would work. Safest would be the new head.

I have heard of people on this site heli coiling one.....but that doesn't seem like a very good solution for the main place on the head that takes the main punch of compression and firing. And to weld one back up and tap it would be difficult to get back in the exact location. A new head would seem like the best bet.....just always be carefuel when tightening sparkplug ( find out the correct lbs. to torque it to) and always use some form of anti-seize gel on the threads so it can be taken out easily

[DieselBoy]

even the honda torque specs are some tight... i snapped a head cover bolt with a torque wrench to the right lbs which seemed some risky, and i broke one... fixed now though!

[prepracing]

Originally posted by DieselBoy
even the honda torque specs are some tight... i snapped a head cover bolt with a torque wrench to the right lbs which seemed some risky, and i broke one... fixed now though!


did u try to torque one of the small 8mm headed bolts to 17 ft lbs ? because only the large bolt in the center is supposed to be 17ft lbs, all the small ones are like 7 - 9 ft lbs. The service manuals do not clearly state that :mad:

[bwamos]

Originally posted by Sjorge300EX
yeah i'm always careful when putting the plug in just because of this reason and i was just wondering how you could fix it if it did happen.

You go to the auto parts store and get a sparkplug repair insert. You tap the existing hole, apply the bonding agent to the insert, thread in the repair insert, then bend down the knurled edges with a screwdriver and hammer. Let dry for 24hrs. Insert spark plug. And, you're done. Quick easy job. I've done it on many cars.

[DieselBoy]

you need to remove the head right due to metal shavings?

[Old Head]

I'd say new head to be safe. I always start the plug by hand to make sure everything is going in ok.

[DieselBoy]

isnt a new head like $600?

[#1rmman220]

just replaced a head my my sled and it was only 150
but this is also a 2 stroke.
dont know what it would be for a four stroke

[yfzfelix]

A heli-coil would work fine if done correct, you could buy alot of heli-coils for the cost of a head, and yes I would remove it to install, I always warm the engine before removing the spark plug it is easier because of expansion, and always use anti seize on the spark plug threads, and don't gorilla torque the plug in, just snug it up and you should be fine

[premiumtommy]

easiest thing to do when replacing spark plug in hole...

cut a 3" piece of vacuum hose from the drain on your carb..the one that runs down the swingarm...

put that on the top connector of the plug and insert...

you will NEVER strip the threads cause the vacuum line will slip first...

then when snug..i put the plug tool on and just snug it up...

good thing with the vacuum line is you dont have to get close to the head if it is real hot....

[bradrenea]

A helicoil will be just as strong or stronger than the aluminum threads on the head.

[Aceman]

Originally posted by bradrenea
A helicoil will be just as strong or stronger than the aluminum threads on the head.

Exactly, I would have no problem helicoiling a spark plug hole.

[jeremy_283]

HELI-COIL that sucker!