enlarging spark plug hole
#1
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enlarging spark plug hole
Hi Guy's, I am working on doing a gas/glow conversion on a Stihl, 65cc, 4-stroke. The problem is the spark plug hole is for a 10mm plug. I need to enlarge this to standard plug size so my glow plug adapter will fit. I am actually looking for someone who can do this since I do not have the tools or skill to re-drill and re-tap the hole. I tried contacting Mark Brielli but no response so far. Suggestions please. Thanks for your consideration.
#6
RE: enlarging spark plug hole
John,
DO NOT enlarge the hole! The plug hole is VERY close to the valve seats/valves and running a drill/ tap through there will almost certainly hit them. As you may have noticed the head and cylinder is one unit and it is darn expensive to replace.
John
DO NOT enlarge the hole! The plug hole is VERY close to the valve seats/valves and running a drill/ tap through there will almost certainly hit them. As you may have noticed the head and cylinder is one unit and it is darn expensive to replace.
John
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RE: enlarging spark plug hole
Excellent TKG, Just to re-confirm you have a 10mm glow plug adapter that will fit the Stihl, 65cc, 4-stroke? You'll have my order soon. Thanks.
#9
RE: enlarging spark plug hole
The stock plug for the Stihl 65 is an NGK CMR6H, which has a longer threaded length than the CM6. If there is an adapter for a Zenoah G-26, that MIGHT be the way to go.
J
J
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RE: enlarging spark plug hole
I'm real interested in how this works out for you. Please keep this going as I have a 32cc that would consider converting if you have good luck on gas glow.
Jim
Jim
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RE: enlarging spark plug hole
You take a big end mill and you start milling (cutting) untill the thread depth is correct. Zenoah does this on the cylinder for the G-26 EI. The G-26 magneto uses the CMR7H, so they face it down and install the CM-6 in the EI version.
WE DO NOT OFFER THIS SERVICE. Unless you know sombody who works at a machine shop and can do this on the side after you take the engine apart. You might be better converting it to EI and run just gas.
WE DO NOT OFFER THIS SERVICE. Unless you know sombody who works at a machine shop and can do this on the side after you take the engine apart. You might be better converting it to EI and run just gas.