Need help on repair spark plug thread!

spcamno · 08-26-2009, 02:10 PM

Just pick up an used 110cc and the previous owner has stripped spark plug threads.

Anybody knows what's the best (permanent and easy to do repair)?

I was told by someone use the helicoil system but have no experience on it.

Thank you in advance!

TurboT · 08-26-2009, 02:18 PM

Quote:

Originally Posted by spcamno

Just pick up an used 110cc and the previous owner has stripped spark plug threads.

Anybody knows what's the best (permanent and easy to do repair)?

I was told by someone use the helicoil system but have no experience on it.

Thank you in advance!

Ouch!

That is a delicate spot for thread repair. Do you have any experience with any thread repair methods?

IMHO, Wurth Time-Serts are the best thread repair system on the market, however they are hard to acquire for the average person. I've actually never used a helicoil on a spark plug thread but I'm sure they are out there.

You need to be very careful there, as sometimes there's not much to work with metal wise. I would suggest the head comes off to do this so you can see what kind of space you have, and make sure you line up the tooling properly.

spcamno · 08-26-2009, 02:28 PM

Thanks Turbo T for your speedy reply!

I have no experience on spark plug thread repair but do have work on my own cars quite a bit.

I have friends works in the auto body business and he might be able to help me borrow a tap thru his connection.

How hard it is to pull the engine apart?

Do I need any special tools such as valve spring compressor etc?

I am in no big hurry since this is going to be my winter project and my son is currently riding his 110cc mini hummer and having fun so I can pull this thing apart if I have to.

Any tips will be very much appreciated.

Thank you again!

TurboT · 08-26-2009, 02:52 PM

You shouldn't need to remove any internals on the head to repair the spark plug threads. It would merely need to come off as when you do any kind of thread repair there will be shavings and pieces that will fall into the cylinder if it is not off.

I have not seen the inside of one of these motors to know how much space is between the seats and the spark plug hole. Most thread repairs require pre drilling, tapping, and insertion of the new thread piece. So if you have a small amount of space you have to be careful not to drill into the underside of the valve seat. This also needs to be done at the correct angle with no tipping of the drill one way or the other.

We used to do this with a drill press so we could level the components and ensure correct angles.

I don't mean to stress you out about it, but spark plug thread repair is a bit more delicate than fixing an exhaust manifold stud or similar blind hole with more forgiveness.

Reveeen · 08-26-2009, 03:00 PM

Very likely, if desired, you will likely have to buy the helicoil system, as the spark plug is not a "normal" size (smaller than a "regular" plug).
The helicoil system comes with a special tap, that you screw into the existing hole, taking that hole to the size for the thread insert. Most guys apply thick grease to the flutes on the tap to trap the alloy shavings, so it is an "in place" repair, the kit also comes with thread inserts (a couple), and a thread insert tool.
The last time I bought a "kit" it was $65 (quite a few years ago), I have no idea on the current pricing.

This does work, it does work "in place", though I would try waltzing in the back door with some cash in my pocket, or try to buy a used head (engine?).

TurboT · 08-26-2009, 03:21 PM

Quote:

Originally Posted by Reveeen

Very likely, if desired, you will likely have to buy the helicoil system, as the spark plug is not a "normal" size (smaller than a "regular" plug).
The helicoil system comes with a special tap, that you screw into the existing hole, taking that hole to the size for the thread insert. Most guys apply thick grease to the flutes on the tap to trap the alloy shavings, so it is an "in place" repair, the kit also comes with thread inserts (a couple), and a thread insert tool.
The last time I bought a "kit" it was $65 (quite a few years ago), I have no idea on the current pricing.

This does work, it does work "in place", though I would try waltzing in the back door with some cash in my pocket, or try to buy a used head (engine?).

This is a good explanation.

I would add though helicoils have a little tab at the bottom(the thread insert), which is there to allow the tool to twist it into place. Once it is in place, it needs to be 'broken off' or it will block your spark plug. It's a bit of an issue with it being on the head... unless the spark plug threads are different for helicoils, I never used them for this repair.. (again, Time Sert from Wurth)

What part of the country you in?? I'm assuming canada since you said 110 Hummer.(Gio?)

katoranger · 08-26-2009, 03:23 PM

I would recommend just getting a different head. Lots of them out there in the honda clone market and would probably be more cost effective.

They are not difficult to change and require basic tools.

Here is just one example of a replacement.
http://cgi.ebay.com/ebaymotors/Lifan...Q5fAccessories

TurboT · 08-26-2009, 03:33 PM

Quote:

Originally Posted by katoranger

I would recommend just getting a different head. Lots of them out there in the honda clone market and would probably be more cost effective.

They are not difficult to change and require basic tools.

Here is just one example of a replacement.
http://cgi.ebay.com/ebaymotors/Lifan...Q5fAccessories

That is quite cheap. Cheaper than the thread repair kit I'm sure.

However I would say changing the valves and springs from one head to the other without spring compressors and little tools for the keepers might drive you nuts.. and also hope they are the same stem and head size on the valves. Probably are??

Reveeen · 08-26-2009, 05:55 PM

Of course, we are lacking a location, as it would make a difference.

The helicoil kit for spark plugs is different from the rest of the line.

An entire used engine (or what you would call a core engine, new, but replaced under warranty) from Hooper is $100. I am sure, with some digging, one could do better, but if there is a couple of these things in the posters "fleet", maybe this would be a better way to go/think?

changing the valves and springs from one head to the other without spring compressors and little tools for the keepers might drive you nuts

Not if you have 3 hands.

spcamno · 08-26-2009, 06:06 PM

Thank you all for your reply!

Yes, Turbo T I am in Toronto and you hit the nail right on the head about replacing the head due to the uncertainty of the valves and stem size.

My neighbor has two 110cc mini hummer and those two has some differences between my son's mini hummer.

Although they looks identical but the axle diameter is different wheels / tires size is different as well as the swing arm.

So I bet there are more than just a couple of factories in China pumping these machine out so I rather not opening a can of worms by swapping the head and ended up replacing all valves sprockets etc.

I would hope I can just drill and repair it by an insert or whatever system works otherwise I might as well as someone suggested buy an entire engine.

Anybody knows if I can rent the Wurth Time-sert?

TurboT · 08-26-2009, 06:13 PM

Quote:

Originally Posted by spcamno

Thank you all for your reply!

Yes, Turbo T I am in Toronto and you hit the nail right on the head about replacing the head due to the uncertainty of the valves and stem size.

My neighbor has two 110cc mini hummer and those two has some differences between my son's mini hummer.

Although they looks identical but the axle diameter is different wheels / tires size is different as well as the swing arm.

So I bet there are more than just a couple of factories in China pumping these machine out so I rather not opening a can of worms by swapping the head and ended up replacing all valves sprockets etc.

I would hope I can just drill and repair it by an insert or whatever system works otherwise I might as well as someone suggested buy an entire engine.

Anybody knows if I can rent the Wurth Time-sert?

You probably don't want to hear this, but taking the head off and taking it to an engine repair shop that uses Wurth products might be an option.

Labour rates are probably reasonable and you might get it repaired for about $60 plus the cost of the insert...that is if they have one that small.

I used to have one but am in Vancouver so not all that helpful. :?

You are probably looking at a $60-$100 repair anyway you go, either buying the kits and doing it yourself or having someone to do it that already has the tooling.

TurboT · 08-26-2009, 06:14 PM

Quote:

Originally Posted by Reveeen

changing the valves and springs from one head to the other without spring compressors and little tools for the keepers might drive you nuts

Not if you have 3 hands.

Hahaha!

Good one. 8)

katoranger · 08-26-2009, 09:10 PM

I think I saw a head with the valves etc too for about $15 more. I am sure the threads can be repaired, just at what price.

Allen

Weldangrind · 08-27-2009, 12:22 AM

I bought an off brand thread repair kit for my XR; it's called Perma-Coil. It comes with the tap, the installation tool and a handful of inserts. All you need is the specific drill bit (size is indicated on the package) and a tap handle.

No way would I install a thread insert without removing the head. It would be too difficult to remove the tang after installation, and all the aluminum bits would be in the cylinder.

I don't remember what I paid for the kit, but IIRC, it was $40.00.

spcamno · 08-28-2009, 02:32 PM

Quote:

Originally Posted by Weldangrind

I bought an off brand thread repair kit for my XR; it's called Perma-Coil. It comes with the tap, the installation tool and a handful of inserts. All you need is the specific drill bit (size is indicated on the package) and a tap handle.

No way would I install a thread insert without removing the head. It would be too difficult to remove the tang after installation, and all the aluminum bits would be in the cylinder.

I don't remember what I paid for the kit, but IIRC, it was $40.00.

Thank you for your tips!

Looks like it I might have to remove the head to complete the task.

Anybody knows where can I find service manual or links to disassemble the engine?

Also, will the honda ATC 110 head gasket fit these motor or should I get the dedicate chinese made gasket?

Thanks you all for the help!

08-26-2009, 02:10 PM	#1
spcamno Join Date: Oct 2008 Location: Toronto,Canada Posts: 36	Need help on repair spark plug thread! Just pick up an used 110cc and the previous owner has stripped spark plug threads. Anybody knows what's the best (permanent and easy to do repair)? I was told by someone use the helicoil system but have no experience on it. Thank you in advance!
	0

08-26-2009, 03:23 PM	#7
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	I would recommend just getting a different head. Lots of them out there in the honda clone market and would probably be more cost effective. They are not difficult to change and require basic tools. Here is just one example of a replacement. http://cgi.ebay.com/ebaymotors/Lifan...Q5fAccessories __________________ You meet the nicest people on a Honda Clone.
	0

08-26-2009, 09:10 PM	#13
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	I think I saw a head with the valves etc too for about $15 more. I am sure the threads can be repaired, just at what price. Allen __________________ You meet the nicest people on a Honda Clone.
	0

08-27-2009, 12:22 AM	#14
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	I bought an off brand thread repair kit for my XR; it's called Perma-Coil. It comes with the tap, the installation tool and a handful of inserts. All you need is the specific drill bit (size is indicated on the package) and a tap handle. No way would I install a thread insert without removing the head. It would be too difficult to remove the tang after installation, and all the aluminum bits would be in the cylinder. I don't remember what I paid for the kit, but IIRC, it was $40.00. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

08-26-2009, 02:28 PM	#3
spcamno Join Date: Oct 2008 Location: Toronto,Canada Posts: 36	Thanks Turbo T for your speedy reply! I have no experience on spark plug thread repair but do have work on my own cars quite a bit. I have friends works in the auto body business and he might be able to help me borrow a tap thru his connection. How hard it is to pull the engine apart? Do I need any special tools such as valve spring compressor etc? I am in no big hurry since this is going to be my winter project and my son is currently riding his 110cc mini hummer and having fun so I can pull this thing apart if I have to. Any tips will be very much appreciated. Thank you again!
	0

08-26-2009, 02:52 PM	#4
TurboT Join Date: Sep 2008 Location: Surrey, B.C., Canada Posts: 2,185	You shouldn't need to remove any internals on the head to repair the spark plug threads. It would merely need to come off as when you do any kind of thread repair there will be shavings and pieces that will fall into the cylinder if it is not off. I have not seen the inside of one of these motors to know how much space is between the seats and the spark plug hole. Most thread repairs require pre drilling, tapping, and insertion of the new thread piece. So if you have a small amount of space you have to be careful not to drill into the underside of the valve seat. This also needs to be done at the correct angle with no tipping of the drill one way or the other. We used to do this with a drill press so we could level the components and ensure correct angles. I don't mean to stress you out about it, but spark plug thread repair is a bit more delicate than fixing an exhaust manifold stud or similar blind hole with more forgiveness.
	0

08-26-2009, 03:00 PM	#5
Reveeen Join Date: Jun 2009 Location: orbital platform Posts: 741	Very likely, if desired, you will likely have to buy the helicoil system, as the spark plug is not a "normal" size (smaller than a "regular" plug). The helicoil system comes with a special tap, that you screw into the existing hole, taking that hole to the size for the thread insert. Most guys apply thick grease to the flutes on the tap to trap the alloy shavings, so it is an "in place" repair, the kit also comes with thread inserts (a couple), and a thread insert tool. The last time I bought a "kit" it was $65 (quite a few years ago), I have no idea on the current pricing. This does work, it does work "in place", though I would try waltzing in the back door with some cash in my pocket, or try to buy a used head (engine?).
	0

08-26-2009, 05:55 PM	#9
Reveeen Join Date: Jun 2009 Location: orbital platform Posts: 741	Of course, we are lacking a location, as it would make a difference. The helicoil kit for spark plugs is different from the rest of the line. An entire used engine (or what you would call a core engine, new, but replaced under warranty) from Hooper is $100. I am sure, with some digging, one could do better, but if there is a couple of these things in the posters "fleet", maybe this would be a better way to go/think? changing the valves and springs from one head to the other without spring compressors and little tools for the keepers might drive you nuts Not if you have 3 hands.
	0

08-26-2009, 06:06 PM	#10
spcamno Join Date: Oct 2008 Location: Toronto,Canada Posts: 36	Thank you all for your reply! Yes, Turbo T I am in Toronto and you hit the nail right on the head about replacing the head due to the uncertainty of the valves and stem size. My neighbor has two 110cc mini hummer and those two has some differences between my son's mini hummer. Although they looks identical but the axle diameter is different wheels / tires size is different as well as the swing arm. So I bet there are more than just a couple of factories in China pumping these machine out so I rather not opening a can of worms by swapping the head and ended up replacing all valves sprockets etc. I would hope I can just drill and repair it by an insert or whatever system works otherwise I might as well as someone suggested buy an entire engine. Anybody knows if I can rent the Wurth Time-sert?
	0