cross threded spark plug?

[hallstudio]

i purchased a 2002 400EX and when i changed the spark plug i found out the spark plug was cross threded. i have found this product on the web KD Back-Tap 12mm Internal Thread Chaser. anyone ever used one? it sure would save some time. here is a link. http://www.handsontools.com/store/show_product/?product_id=5402768

[PunkA$$]

Are they suggesting you use that with the head on the engine? Sounds like bad news.

[K_Fulk]

That may work. But it would be better to take your head off and tap it from thye good side to the bad side.

As long as you have a service manual its pretty easy. And there will always be someone on here to answer your question if you need help putting it back together.

[mojoe2878]

definently remove the head to tap it regardless of what kind of tap you use or you will get metal shavings in the cylinder.

[Destructo]

I would probably tap it and install a heli-coil for a spark plug.

[torqen2k1]

WOW :eek: that sucks!! But your best bet is to pull the head off and tap it from the good side.The side thats is inside your motor. This also ocurred to my friends truck and we pulled the head off.

[hallstudio]

seems like if you start the tap on good threeds and work your way out as long as there is grease on the tap the majority if not all the shavings would end up on the outside.you guys are probably right im just lazy and dont want to take the head off.

[QuAdEr 317]

i used heli coil

[mojoe2878]

Originally posted by hallstudio
seems like if you start the tap on good threeds and work your way out as long as there is grease on the tap the majority if not all the shavings would end up on the outside.you guys are probably right im just lazy and dont want to take the head off.
you are right, the majority of the shavings will end up on the outside if you start on the good side and put grease on the tap.
but how are you going to start a tap on the good side and work your way to the outside if the head is still on the motor?:confused: ;)

[hallstudio]

looks like this tap expands via a screw at the top. so you slide the tap down to the good threads then expand it and work your way out. at least i think this is how it works and four $40 it better do somthing cool like that. hell i can try it and if i dont think it cleared the shavings i can take the head off and clean it. in fact i could spend even more money and buy one of those tiny video cameras with a light like the doctors use for surgery and look inside after i am done to check. .......or just buy a new 400EX. that would definetly be the easy way to fix it.

[mojoe2878]

Originally posted by hallstudio
looks like this tap expands via a screw at the top. so you slide the tap down to the good threads then expand it and work your way out. at least i think this is how it works and four $40 it better do somthing cool like that. hell i can try it and if i dont think it cleared the shavings i can take the head off and clean it. in fact i could spend even more money and buy one of those tiny video cameras with a light like the doctors use for surgery and look inside after i am done to check. .......or just buy a new 400EX. that would definetly be the easy way to fix it.
oh ok. i finally looked at the link you posted to see what it was.
never seen anything like that before. let us know how it works, i might have to get me one of those if it works like they say it does.

i had this happen to 4 spark plugs on my truck (the guy put the wrong spark plugs on) & we just helicoiled all of them...can you helicoil them with a quad?

[AdvantageCycle]

good luck, but more than likely, the threads are history, chaser or not. Heli-coils are good, but when I do spark plug thread repair I use a Time-sert. Its 10 times better of a job for several reasons. If you need further assistance, contact me at the shop.

[BSTURDIVANT]

The biggest problem with the 400 is caused by dirt in the spark plug area. Make sure you clean it out with a small screw driver and air (with spark plug in the hole).Threads are probably good in the bottom!