To anyone that can help I am looking for the cheapest but best way to replace the threads in my spark plug hole on my mercury motor.

Its sad cause i bought this boat its my first, and i havent even been able to take it out on the water yet.

any help is greatly appreciated! thanx JJ

helicoil... instructions included with coil, buy at most any parts store.

JJ,
You probably don't have the tools to do the job. You need a helicoil(spelling??) put in. What they will do is rethread the hole and screw this masive thread(helicoil) in place that decreases the hole diamiter back down to the spark plug thread size. The problem you have is it takes some pretty special tools to do this so you will most likely need to take it in to a shop. In addition, they may have to take your head off so that the metal shavings do not get into your piston cylinder. This is not something I would recommend if you are not a mechanic.
If you are a do-it-yourselfer...you can remove the head and take it up to any marine or auto shop to have this done. You will need all the proper gaskets (new) to put the head back in place as well as a torque wrench and an overhaul manual for that engine that has torque specs.
It has been a long time since I have had to do this and I cannot remember if the head removal was required.
Good luck.
F_H

[This message has been edited by foul_hook (edited 09-24-2003).]

No head to remove on your motor(old posts). Take it to the shop and be prepared to spend some $. sorry
PS-Locktight makes a kit to replace bad threads. Don't know if it'll work on cylinder heads,(much less marine applications)but it might be worth a shot on your old motor.

Ok listen carefully. This is VERY hard to do right and you get one try! Helicoil makes a kit to repair damaged plug holes. It should come with the drill,tap and coils. read the instuctions at least three times. Use grease when you tap or drill. SLOW is important. Take your time. the grease will collect the shavings. You may get some in the hole. take a rag/ towel any thing that will get in there to remove as much as possible. alum. is soft. the fine stuff will past.Good luck Charlie blue wave ASE Master tech. and get it on center! straight and true.LOL

About the grease. you put it on the tap/ drill flukes. the area in between. keep the hole as clean as possible. and remove the shavings offen. You can have a mechanic do it. We never warranty such a repair.But if done right you will get on the water soon. You will have be carefull on plug replacement as well in the future. 14lbs of torque is not much. Overtightens is how it happeneds. never use a black plug in alum. Charlie

Thanx for all the replys so far, i will check in on that kit, but can i buy this kit at ??????? west marine??? im in sanantonio any help guys thanx i wll keep you posted!

You can get it at AutoZone, Hi-Lo, etc. Go to an auto parts store. West Marine doesn't know how to work on an engine (in my experiences...).

JJ,
I have done the same type of repair to a lawnmower. You can preform this repair at home. You need the coil, a rethreader the size of the coil, and a drill. simply drill out the hole to match the size of the coil. screw the coil into the hole. screw spark plug into coil until it is tight in the coil and in the manifold. I am not a mechanic of any sort and I was able to do this in the manner of about 15 minutes. The coil can be purchased at ANY auto parts store. I got mine at a Car Quest Parts store. Hope this helps.

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Don't hunt what you can't kill.

ok i got the heli coil kit than kgod it was only 12 bucks i will keep ya posted on how it goes!

One more thing, when you are done with your repair. leave the plug out. fire up the motor and shut it down as soon as it starts. any small stuff with blow out. LOL

well i have an old dentist vacume tube that i plan on sticking in there and trying to suck out anything that might end up in the cylinder, i have been working on cars since i was 10 but never ran into this problem, i guess you learn somthing new every day huh, recently we had this problem with a ford escort and i just took off the head and took it down to the machine shop and i am assuming this is what they did, i suppose it wont be that hard i have just never worked on any boat and ths is my first so i dont want to screw it up you dig anyway i will let you guys know when i have completed this and how it went!

so what the new's. ???????????????????????????????????????????????????????????????????????