Cylinder Head Replacement Stripped Spark Plug

yozalo · 03-20-2012, 05:34 PM

110cc is lying around, with a stripped spark plug. I bought a new cylinder head but it has no gaskets. After watching a couple of videos on youtube, I'm nervous to remove the cylinder. Heres a link to the youtube video:

I don't want to mess around with the engine...I was thinking about using a heli coil instead, but it would be a waste of money as I have already purchased a cylinder head.

How hard is it to replace the cylinder head for a person with little technical skills. Can I reuse the gaskets, since the new cylinder head did not come with any?

FastDoc · 03-20-2012, 06:16 PM

It's not hard as long as you are methodical.

To use a helicoil or similar you'd have to remove the head (to do it right) anyways.

You may be able to reuse the gaskets but it might leak and you'd have to do the work all over to fix it, and gasket kits are cheap.

Weldangrind · 03-20-2012, 09:01 PM

Hey Yozalo! How's it going?

Thanks for the link to the CG 125 engine; it's very informative for me, but it's not the right video for you. Your 110 is a horizontal engine, much like the little Hondas that date back to the sixties. It's a very simple little engine to work on, and the most important aspect of replacing the head is cam timing. Honda made that very easy, as you'll see in part one and part two of this vid:

A Helicoil is a good repair, but like Doc says, you need to remove the head to do it properly. If any schrapnel is left in the engine, it could carve up the cylinder wall, create smoke and lose power. When you see what the valves look like on your engine, you'll be glad that you swapped the new head on.

Gaskets are really cheap on eBay; buy new ones.

FLASHLIGHTBOY · 03-21-2012, 12:32 AM

most repair shops will do the helicoil repair without removing the head... common practice for them.. I have had it do masny times before... all you need to do is to blow out the cylinder good... it is easy to have this do by a repair person.. cost you money... the new head and the gaskets are the other way to do it... you can do all the repair your self.. just do as it says above.. take your time... have a manual and the parts.. either way.. it is your choice.. and your money... too bad you bought the head.. that probadly would have paid the cost to repair it at the repair shop..

TCCKSR · 03-21-2012, 02:17 AM

hey its a chinese quad, nothing hurting having spare parts around.

The head replacement or cylinder re & re is not that hard.

If you go look you will see from last summer a thread where I completely redid the top end of one of my sport quads. Yanked the head, pulled the cylinder, replaced the piston, wrist pin and clips, then reinstalled the cylinder and head to have it all fire up 1st try.

Nothing to it!!

katoranger · 03-21-2012, 08:17 AM

If you have not seen the videos done by this guy. Alot of good info on horizontals.

Weldangrind · 03-21-2012, 11:09 AM

Quote:

Originally Posted by katoranger

If you have not seen the videos done by this guy. Alot of good info on horizontals.

X2. I was originally looking for vids from this gentleman, when I found the other links I posted. Very sharp guy.

yozalo · 03-21-2012, 02:50 PM

Thanks for everyones help...there are more videos than I expected, just have to use the right key terms.

Would this gasket kit be fine:
http://www.ebay.com/itm/Gasket-engin...741408&vxp=mtr

It's for the 125cc....but it's the cheapest I could find. Shipping to Canada costs more than the product itself, all the other ones for 110cc were $20+ from USA...

yozalo · 03-21-2012, 02:51 PM

Quote:

Originally Posted by Weldangrind

Quote:

Originally Posted by katoranger

If you have not seen the videos done by this guy. Alot of good info on horizontals.

X2. I was originally looking for vids from this gentleman, when I found the other links I posted. Very sharp guy.

This video was also quite informative:

Weldangrind · 03-22-2012, 02:04 AM

Quote:

Originally Posted by yozalo

Thanks for everyones help...there are more videos than I expected, just have to use the right key terms.

Would this gasket kit be fine:
http://www.ebay.com/itm/Gasket-engin...741408&vxp=mtr

It's for the 125cc....but it's the cheapest I could find. Shipping to Canada costs more than the product itself, all the other ones for 110cc were $20+ from USA...

I answered this question in a PM to Yozalo, but it might benefit others; the 125 has the wrong bore size for the 110, so the gasket would likely fail.

yozalo · 03-23-2012, 04:41 PM

Thought it might be better beneficial to post my question on the forum, rather than bugging weldangrind for help.

It was more harder than I expected. One job ended up being five other tasks I had to do just to get out the cylinder head.

I had to remove the whole entire engine to access, and remove the cylinder. The new cylinder was the wrong size - even though they looked the same, the design was slightly different. Not sure how to explain this but, when I put in the cam shaft, it wouldn't line up correctly with the arm valve rocker.
http://www.buyatvsonline.com/bmx-par...ly-p-2062.html
Look at the right hand image...those are the two arms I am referring to.

I'm just going to use the same cylinder, and use a heli coil. I will try with a fine thread to see if that would fix it....

Now I have a couple of questions:
1) Is the valve spring supposed to compress, I am trying to spin the shaft, and it won't go all the way since the spring will not compress. Not sure if it is supposed to go down by hand.
2) I was watching this video:

Do I have to gap the valves with the tool?
3) The valves are black at the end.....it has gunk built up on it. What could be the cause of the problem...it was pitch black.

Weldangrind · 03-24-2012, 01:31 AM

I responded to Yozalo's questions by PM, and he sorted some of it out on his own.

To clarify:

The valves can be cleaned with a small wire brush, but care must be taken to not brush the gasket surface, which must be perfectly clean and flat. Some duct tape over the gasket surface to protect it while cleaning the valves is a good idea.

The valves should be set after everything is back together. A cheap feeler gauge is needed. Youtube can explain the process much more efficiently than I can.

yozalo · 03-27-2012, 05:23 PM

The head was the wrong size....

I'm going to use a Heli coil kit...what is the correct size for the CR7 HSA spark plug. I was looking around, and it seems like m10 x 1 is the correct one? Would like to confirm before buying online...

FastDoc · 03-27-2012, 05:34 PM

I bet you could bring the spark plug to a local auto parts store and find a helicoil that will fit.

yozalo · 03-27-2012, 05:38 PM

Quote:

Originally Posted by FastDoc

I bet you could bring the spark plug to a local auto parts store and find a helicoil that will fit.

They only have one size...........m10 x 1.5 (meant to fit drain bolts...)

03-20-2012, 05:34 PM	#1
yozalo Join Date: Apr 2009 Posts: 330	Cylinder Head Replacement Stripped Spark Plug 110cc is lying around, with a stripped spark plug. I bought a new cylinder head but it has no gaskets. After watching a couple of videos on youtube, I'm nervous to remove the cylinder. Heres a link to the youtube video: I don't want to mess around with the engine...I was thinking about using a heli coil instead, but it would be a waste of money as I have already purchased a cylinder head. How hard is it to replace the cylinder head for a person with little technical skills. Can I reuse the gaskets, since the new cylinder head did not come with any?
	0

03-20-2012, 06:16 PM	#2
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	It's not hard as long as you are methodical. To use a helicoil or similar you'd have to remove the head (to do it right) anyways. You may be able to reuse the gaskets but it might leak and you'd have to do the work all over to fix it, and gasket kits are cheap. __________________ Happy to serve.
	0

03-20-2012, 09:01 PM	#3
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	Hey Yozalo! How's it going? Thanks for the link to the CG 125 engine; it's very informative for me, but it's not the right video for you. Your 110 is a horizontal engine, much like the little Hondas that date back to the sixties. It's a very simple little engine to work on, and the most important aspect of replacing the head is cam timing. Honda made that very easy, as you'll see in part one and part two of this vid: A Helicoil is a good repair, but like Doc says, you need to remove the head to do it properly. If any schrapnel is left in the engine, it could carve up the cylinder wall, create smoke and lose power. When you see what the valves look like on your engine, you'll be glad that you swapped the new head on. Gaskets are really cheap on eBay; buy new ones. __________________ 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

03-21-2012, 12:32 AM	#4
FLASHLIGHTBOY Join Date: May 2009 Location: SASKATOON Posts: 1,161	helicoil most repair shops will do the helicoil repair without removing the head... common practice for them.. I have had it do masny times before... all you need to do is to blow out the cylinder good... it is easy to have this do by a repair person.. cost you money... the new head and the gaskets are the other way to do it... you can do all the repair your self.. just do as it says above.. take your time... have a manual and the parts.. either way.. it is your choice.. and your money... too bad you bought the head.. that probadly would have paid the cost to repair it at the repair shop.. __________________ DEALER FOR ZSTAR & GIO PRODUCTS, TAOTAO ABIBABA ATV ETC
	0

03-21-2012, 02:17 AM	#5
TCCKSR Join Date: Feb 2011 Location: Langley, BC Posts: 298	hey its a chinese quad, nothing hurting having spare parts around. The head replacement or cylinder re & re is not that hard. If you go look you will see from last summer a thread where I completely redid the top end of one of my sport quads. Yanked the head, pulled the cylinder, replaced the piston, wrist pin and clips, then reinstalled the cylinder and head to have it all fire up 1st try. Nothing to it!! __________________ TCCK: The Coca-Cola Kid......... Hide your pepsi or I take your soul !!
	0

03-21-2012, 08:17 AM	#6
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	If you have not seen the videos done by this guy. Alot of good info on horizontals. __________________ You meet the nicest people on a Honda Clone.
	0

03-21-2012, 02:50 PM	#8
yozalo Join Date: Apr 2009 Posts: 330	Thanks for everyones help...there are more videos than I expected, just have to use the right key terms. Would this gasket kit be fine: http://www.ebay.com/itm/Gasket-engin...741408&vxp=mtr It's for the 125cc....but it's the cheapest I could find. Shipping to Canada costs more than the product itself, all the other ones for 110cc were $20+ from USA...
	0

03-23-2012, 04:41 PM	#11
yozalo Join Date: Apr 2009 Posts: 330	Thought it might be better beneficial to post my question on the forum, rather than bugging weldangrind for help. It was more harder than I expected. One job ended up being five other tasks I had to do just to get out the cylinder head. I had to remove the whole entire engine to access, and remove the cylinder. The new cylinder was the wrong size - even though they looked the same, the design was slightly different. Not sure how to explain this but, when I put in the cam shaft, it wouldn't line up correctly with the arm valve rocker. http://www.buyatvsonline.com/bmx-par...ly-p-2062.html Look at the right hand image...those are the two arms I am referring to. I'm just going to use the same cylinder, and use a heli coil. I will try with a fine thread to see if that would fix it.... Now I have a couple of questions: 1) Is the valve spring supposed to compress, I am trying to spin the shaft, and it won't go all the way since the spring will not compress. Not sure if it is supposed to go down by hand. 2) I was watching this video: Do I have to gap the valves with the tool? 3) The valves are black at the end.....it has gunk built up on it. What could be the cause of the problem...it was pitch black.
	0

03-24-2012, 01:31 AM	#12
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	I responded to Yozalo's questions by PM, and he sorted some of it out on his own. To clarify: The valves can be cleaned with a small wire brush, but care must be taken to not brush the gasket surface, which must be perfectly clean and flat. Some duct tape over the gasket surface to protect it while cleaning the valves is a good idea. The valves should be set after everything is back together. A cheap feeler gauge is needed. Youtube can explain the process much more efficiently than I can. __________________ 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

03-27-2012, 05:23 PM	#13
yozalo Join Date: Apr 2009 Posts: 330	The head was the wrong size.... I'm going to use a Heli coil kit...what is the correct size for the CR7 HSA spark plug. I was looking around, and it seems like m10 x 1 is the correct one? Would like to confirm before buying online...
	0

03-27-2012, 05:34 PM	#14
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	I bet you could bring the spark plug to a local auto parts store and find a helicoil that will fit. __________________ Happy to serve.
	0