Spark Plug Hole Stripped *Removing* a Spark Plug???

RJM62

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Geek on the Hill
I've changed hundreds of spark plugs in pretty much every kind of engine there is, and this has never happened to me before. The hole got stripped while removing the spark plug from my snow blower.

Actually, I've never stripped a spark plug hole installing one, either. But stripping the hole while removing one I would have thought impossible until today. Granted, it's been in there for four or five years, but still.

I ordered the re-threader and insert kit from Amazon because no one within a hundred miles of me seems to have one in stock, and it should arrive Monday. There's no snow to speak of in the forecast by then, so it's no big deal.

The hardest part will be getting the metal shavings out of the cylinder without taking the head off, which I'd rather not do if I can avoid it. One of the local rednecks says to tip the machine on its side and flush the cylinder out with water, letting the water drain out the spark plug hole. That sounds a bit insane to me, although I can't really put my finger on why.

My current plan is to put some light oil in there, drain it, repeat a few times, put the old plug back in and run it for a while, and then put the new plug in. Oil seems better than water to me; but the redneck pointed out that water is denser than oil and will float the shavings out. Pretty smart rednecks we have around here.

Another redneck says don't worry about it because any shavings will blow out the exhaust as soon as I fire the engine up. That may also be true. But what will they damage on the way out?

Nothing's ever easy...

Rich
 
I think I would be tempted stick a cheap Harbor Freight blow gun in the spark plug hole and blow as much as possible out. Alternatively, one of the cheap magnetic pickup tool might fit into the cylinder get everything too. Any fluid would probably have mixed results with shavings...
 
I think I would be tempted stick a cheap Harbor Freight blow gun in the spark plug hole and blow as much as possible out. Alternatively, one of the cheap magnetic pickup tool might fit into the cylinder get everything too. Any fluid would probably have mixed results with shavings...

The air is another possibility. The magnet, not so much with an aluminum head. Thanks.

Rich
 
Coat the tap in grease. Since the metal chips will stick you have to cut a little and back it out to clean. Then recoat with grease and repeat until it’s fully cut. Keeps about 90% of the shavings from falling inside the cylinder
 
Aluminum..???

Fix the threads.

Leave the plug out, turn off the fuel and pull the rope several times as if you hate that machine. The only way to ensure all shavings are out is to remove the head. Otherwise replace the plug and fire it up.
 
It’s so hard living in the middle of nowhere, especially when you’re only an hour from the biggest megalopolis on the planet. This world has nothing to offer. God bless the United States of Amazon. ;)
 
It’s so hard living in the middle of nowhere, especially when you’re only an hour from the biggest megalopolis on the planet. This world has nothing to offer. God bless the United States of Amazon. ;)

Well, it's more like 3 1/2 hours. And the benefits are worth the inconveniences.

Rich
 
Aluminum..???

Fix the threads.

Leave the plug out, turn off the fuel and pull the rope several times as if you hate that machine. The only way to ensure all shavings are out is to remove the head. Otherwise replace the plug and fire it up.

Actually... it has an electric starter that I never use. This might be a good time to use it. Thanks.

Rich
 
Coat the tap in grease. Since the metal chips will stick you have to cut a little and back it out to clean. Then recoat with grease and repeat until it’s fully cut. Keeps about 90% of the shavings from falling inside the cylinder

That was part of the plan, too. But thanks.

Rich
 
Well, it's more like 3 1/2 hours. And the benefits are worth the inconveniences.

Rich

Where in the Catskills is 3.5 hours away from a large population center that has stores? I thought I was remote living in the Adirondacks, but apparently the Catskills are the real deal when it comes to the wilderness.
 

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I would move the piston close to TDC, then heavily grease a piece of shop rag and push it in there, trying to have it end up just below the end of the plug hole threads, but after making sure I had a pair of long nose pliers that I could use to retrieve it. You could pull it out a couple of times as you drill and tap for the helicoil, cleaning and regreasing it each time. As mentioned, heavily grease the drill and the tap so that chips are caught as close to the origin as possible.

That said, I don't think a small quantity of aluminum chips are going to cause any trouble. Maybe if one catches on the exhaust valve seat you'd get some misfiring but the heat and the pounding from the valve would clear it pretty quickly IMO. So I would try all my tricks to minimize the chips in there, but not be terrified to finally start the beast.
 
Where in the Catskills is 3.5 hours away from a large population center that has stores? I thought I was remote living in the Adirondacks, but apparently the Catskills are the real deal when it comes to the wilderness.

Delaware County. The "biggest megalopolis on the planet" would be New York City, I'd think. That's about 3 1/2 hours to get into the city, and about half an hour less on the return trip, for reasons that only make sense if you think of it in terms of a funnel.

I basically checked the Web sites of every company I could think of that might have a 14mm thread repair kit in stock, and checked their store inventories within a 50-mile radius of Delaware County, Kingston, Binghamton, Albany, and Middletown. So I checked in all directions. Many stores have them on their sites and are willing to ship, but none of them had them in a physical store.

Surely there are stores that don't have Web sites that may have one, but I really didn't want to go calling them all. Monday's soon enough; and Amazon's price was about half of what anyone else wanted.

This sort of thing illustrates the real reason why Amazon is kicking brick-and-mortar's ass. This morning I went to buy the spark plug, checking all the local stores that one would expect to have spark plugs (including the store where I bought the snow blower). None of them had it.

I kept working my way outwards and finally found it in Tractor Supply, about 27 miles away, which was okay because I had other errands to run in the vicinity. But if I didn't, I would have ordered it from Amazon. And then after the threads stripped, I spent hours trying to find a Helicoil or something vaguely resembling one at a physical store, but to no avail.

I had a similar experience a few days ago trying to buy a charger for a vape battery. It's an 18650 battery that's also used in a bunch of flashlights. I wanted an external charger so I could charge the extra batteries while using the vape. Not one store within 50 miles -- including the one where I bought the vape and batteries, and stores that sell flashlights that use that battery -- had a charger for them. Amazon, on the other hand, had bazillions of them.

The long and short of it is that Amazon is kicking everyone else's asses because they actually have stuff. I try my best to shop local, but unless you're looking for something with rapid turnover, you're probably going to wind up buying it from Amazon in the end.

Rich
 
I would move the piston close to TDC, then heavily grease a piece of shop rag and push it in there, trying to have it end up just below the end of the plug hole threads, but after making sure I had a pair of long nose pliers that I could use to retrieve it. You could pull it out a couple of times as you drill and tap for the helicoil, cleaning and regreasing it each time. As mentioned, heavily grease the drill and the tap so that chips are caught as close to the origin as possible.

That said, I don't think a small quantity of aluminum chips are going to cause any trouble. Maybe if one catches on the exhaust valve seat you'd get some misfiring but the heat and the pounding from the valve would clear it pretty quickly IMO. So I would try all my tricks to minimize the chips in there, but not be terrified to finally start the beast.

Another good idea. Thanks.

Rich
 
Simply put a new head on it. then use nickel antiseze.

You folks can't believe how backward that part o NY really is. 150 miles from the GW bridge nd we didn't have electricity until 1959.
Delaware County is so far out in the sticks they pump sunlight to them.
 
There ia a very good small engine repair in Walton. might just have what you need.

McAdams he's behind the NAPA.
 
There ia a very good small engine repair in Walton. might just have what you need.

McAdams he's behind the NAPA.

NAPA? Like where they sell helicoil kits and stuff like that for spark plug repairs? :D
 
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depending on which engine you have it may be cheaper just to get a new head.... Had a similar issue on a lawnmower a while back with a Briggs and Stratton engine... head and gasket was $25 delivered... Two hours later I had no excuse for getting the lawn cut..

as for getting the savings out... would a shop vac do the trick?
 
There ia a very good small engine repair in Walton. might just have what you need.

McAdams he's behind the NAPA.

I've heard the name. If the rethread doesn't work I'll give him a call. Thanks.

Rich
 
depending on which engine you have it may be cheaper just to get a new head.... Had a similar issue on a lawnmower a while back with a Briggs and Stratton engine... head and gasket was $25 delivered... Two hours later I had no excuse for getting the lawn cut..

as for getting the savings out... would a shop vac do the trick?

The head is ~ $100.00, including the gasket. But it looks like a real pain in the ass to get to. If I have to replace it, however, I'll either do it or pay the guy Tom recommended to do it. I think the tap and insert should do the trick, though.

I thought about fitting a small-diameter hose to the shop vac, too. I probably could just redneck it with some duct tape seeing as how it's a one-time deal.

I have a hunch that I'm going to use multiple methods to deal with the shavings. Do the grease around the tap, the shop vac, the rag in the cylinder, and so forth. Between them all it should get everything out, or at least enough that what remains is nothing to worry about.

Rich
 
NAPA? Like where they sell helicoil kits and stuff like that for spark plug repairs? :D

Actually, I checked NAPA. None of the local stores have a 14mm kit in stock. They can all get it by Monday, but Amazon can get get it to my house by Monday and save me 60 miles of driving to the nearest store (and about half the cost).

Had I called earlier, NAPA probably could have gotten it by tomorrow. I wasted too much time looking for someplace that had it today rather than calling NAPA and asking them to get one for me by tomorrow.

Rich
 
You can tap that hole and have the chips out if you turn the crank until the exhaust is open and the intake closed, tape an air hose to the muffler and control the airflow with a C-clamp on the hose, and let a little breeze blow out the plug hole as you tap. The chips will blow out instead of falling into the cylinder.
Wear safety glasses.

Those threads will indeed strip on removal if the aluminum has carboned itself to the plug threads. All it takes is for one bit of thread to tear away, stuck to the plug, and it rips everything out as it goes. Use a bit of anti-seize on the threads.
 
You can tap that hole and have the chips out if you turn the crank until the exhaust is open and the intake closed, tape an air hose to the muffler and control the airflow with a C-clamp on the hose, and let a little breeze blow out the plug hole as you tap. The chips will blow out instead of falling into the cylinder.
Wear safety glasses.

Those threads will indeed strip on removal if the aluminum has carboned itself to the plug threads. All it takes is for one bit of thread to tear away, stuck to the plug, and it rips everything out as it goes. Use a bit of anti-seize on the threads.

Now that's pretty ingenious. Thanks.

Rich
 
I was going to go with the shop vac and duct taping on something small and tubular... I have some small aluminum tubing around here that I would use... and then you could also stick it down inside the head after backing out the tap. You’ve already got that one on your list, though.

Reminded me that I should probably change the plug on the John Deere. I don’t know why, the thing blows fire out the exhaust and still manages enough compression to blow snow better than any newer snowblower I’ve ever had. I’m going to be sad when that silly thing really breaks someday.
 
I was going to go with the shop vac and duct taping on something small and tubular... I have some small aluminum tubing around here that I would use... and then you could also stick it down inside the head after backing out the tap. You’ve already got that one on your list, though.

Reminded me that I should probably change the plug on the John Deere. I don’t know why, the thing blows fire out the exhaust and still manages enough compression to blow snow better than any newer snowblower I’ve ever had. I’m going to be sad when that silly thing really breaks someday.

I'll probably use some extra tubing I have for the water changer for my aquatic tanks (unless it's fused to the fittings -- I have to check) and use that as one of the shavings-removal steps. None of them are especially time-consuming, so I can use more than one method. I can also buy some tubing at a local hardware store. Tubing they have. Spark plugs and Helicoils, not so much.

The manual for my snow blower says to inspect or replace the spark plug every 100 hours or before putting it into storage (so basically annually). I'm probably within the 100 hours, but now I know why the annual replacement is important. Live and learn, I guess.

The store that really surprised me for not having a Helicoil or similar tool in stock (other than the various auto parts stores, who had some sizes, but not 14mm) was Tractor Supply because they stock all sorts of obscure parts and supplies related to power equipment. This is only the second time that they didn't have something related to tools or power equipment that I needed.

Advance Auto and NAPA were also disappointing. I've found them to have decent inventory overall. I guess 14mm must be an unusual size for vehicle engine spark plugs, and they're primarily vehicle-oriented stores. That's just a guess, by the way. I really have no idea how many car engines use 14mm spark plugs.

Rich
 
You don't say what kind of engine, but pulling the head shouldn't be that hard to get the chips out. Fix the hole or get a new head. Use anti seize, hand tighten the spark plug then get a torque wrench. Over tightening can screw the pooch here and cause this.
 
Yes. Happened to me on a 1990 Volvo. The entire thread came out with the plug. Had install a threaded insert with the car parked on a NYC street. I picked up the shavings with grease and blew out what was left with a can of electronics cleaner. Had to de-grease the threads as well as that brand of insert was seated with some kind of epoxy.

With a small engine that doesnt have a turbo or cathalytic converter I would not worry about the shavings. They'll come out the first time you fire up.
 
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If you go with the shop vac plan, make sure that you have taken steps to ensure that you don’t pull fuel/vapor from the intake, through the engine and into the shop vac...
 
You don't say what kind of engine, but pulling the head shouldn't be that hard to get the chips out. Fix the hole or get a new head. Use anti seize, hand tighten the spark plug then get a torque wrench. Over tightening can screw the pooch here and cause this.

LCT, I think 208cc. Pulling the head is easy. Getting to the head, not so much. It would be more time-consuming than anything else, in all honesty.

Rich
 
Actually, I checked NAPA. None of the local stores have a 14mm kit in stock. They can all get it by Monday, but Amazon can get get it to my house by Monday and save me 60 miles of driving to the nearest store (and about half the cost).

Had I called earlier, NAPA probably could have gotten it by tomorrow. I wasted too much time looking for someplace that had it today rather than calling NAPA and asking them to get one for me by tomorrow.

Rich

As I said, God Bless the United States of Amazon.
 
LCT, I think 208cc. Pulling the head is easy. Getting to the head, not so much. It would be more time-consuming than anything else, in all honesty.

Rich

It'll probably be ok, probably. I had a generator suck in a screw that held the choke plate its shaft. Wrecked the rings and scratched up the cylinder. Now the low oil shutoff kicks in before the gas tank is empty, granted it was a steel screw, not aluminum shavings.

If you are going to Amazon anyway, get a $35 dental cam that will fit through the hole to find the chips, then use a wire with something tacky to pull them out. A little time consuming but probably less so than pulling the head.
 
LCT, I think 208cc. Pulling the head is easy. Getting to the head, not so much. It would be more time-consuming than anything else, in all honesty.

Rich

LCT first time I've heard of them, I guess I stopped paying attention. Tecumseh after the lawsuit, should be good engines. Honestly, unless they have really changed them, which I doubt, they come apart pretty easily. Just deal with the gas first. I've taken mine apart many times to evict mice, before I smartened up and sealed the shed. If you decide to do it, the total labor part should be less than 3 hours if you are handy, and if you are like me, most of that time will be spent looking for your tools.
 
LCT first time I've heard of them, I guess I stopped paying attention. Tecumseh after the lawsuit, should be good engines. Honestly, unless they have really changed them, which I doubt, they come apart pretty easily. Just deal with the gas first. I've taken mine apart many times to evict mice, before I smartened up and sealed the shed. If you decide to do it, the total labor part should be less than 3 hours if you are handy, and if you are like me, most of that time will be spent looking for your tools.

Liquid Combustion Technology. They're U.S.-owned, but the engines are made in China. The Shanghai operation is one of the growing number of Chinese entities who are trying to change the reputation of Chinese products.

They're excellent engines, in my experience. To my knowledge, they all carry at least 5-year warranties, but I don't anyone who's needed to use one. A lot of the Husqvarna engines are re-badged LCT engines. Whether under the Husqvarna or LCT badge, Husqvarna handles the warranties on the ones powering their equipment.

Unlike many of my friends, I actually cheer Chinese manufacturers who are trying to put out quality stuff. I'm old enough to remember when "Made in Korea" and "Made in Japan" were synonymous with "cheap ****." But as those countries cleaned up their acts, their standards of living rose, and we became competitive with them again.

Whether that will happen with China remains to be seen. Korea and Japan didn't have to deal with state capitalist governments. But my hunch is that prosperity will bring reform in China. No matter how powerful a government is, the people are always more so. We've seen proof of that in my lifetime, too.

Rich
 
I have to admit @RJM62, I’m going to be sad when China does catch up on quality of life because I have a minor addiction to hunting through AliExpress and BangGood for ultra cheap crap I don’t need. Haha. I don’t often buy it, but once in a while I see something I know is a complete knock off of something better at 1/10 the price and my curiosity gets the better of me and I have to buy it to see how bad or good it is. Haha.

And both sites and a few others are just incredible pricing on hobby electronics components. “Oh, you’d like 10,000 assorted 1/4-watt resistors in useful sizes mailed to your door for $3? Sure. We got that! LOL. Haven’t run into TOO many dodgy components yet. Electrolytic capacitors are always suspect out of no name shops in China, but other jellybean components and even quite a few completely assembled boards for experimenting or integrating into a bigger project, are often so low priced you just order three of them just to have them on hand.

They do, however, rip off everything and copy everything. Copycat boards only bother me when it’s a small time author of something who went to the trouble of spinning up some boards for other people to try, when he’s undercut by his own board fabricator making clones of his work for pennies on the dollar.

It’s a wonderful time to be or learn to be an electronics hobbyist. So much cheap and reasonably well made stuff for fractions of what that stuff would have cost to make when I started playing with electronics.

Captain Zilog may be long dead, but Shenzhen sure can crank out the quantity of parts... not always the quality, but still amazing.
 
I have to admit @RJM62, I’m going to be sad when China does catch up on quality of life because I have a minor addiction to hunting through AliExpress and BangGood for ultra cheap crap I don’t need. Haha. I don’t often buy it, but once in a while I see something I know is a complete knock off of something better at 1/10 the price and my curiosity gets the better of me and I have to buy it to see how bad or good it is. Haha.

And both sites and a few others are just incredible pricing on hobby electronics components. “Oh, you’d like 10,000 assorted 1/4-watt resistors in useful sizes mailed to your door for $3? Sure. We got that! LOL. Haven’t run into TOO many dodgy components yet. Electrolytic capacitors are always suspect out of no name shops in China, but other jellybean components and even quite a few completely assembled boards for experimenting or integrating into a bigger project, are often so low priced you just order three of them just to have them on hand.

They do, however, rip off everything and copy everything. Copycat boards only bother me when it’s a small time author of something who went to the trouble of spinning up some boards for other people to try, when he’s undercut by his own board fabricator making clones of his work for pennies on the dollar.

It’s a wonderful time to be or learn to be an electronics hobbyist. So much cheap and reasonably well made stuff for fractions of what that stuff would have cost to make when I started playing with electronics.

Captain Zilog may be long dead, but Shenzhen sure can crank out the quantity of parts... not always the quality, but still amazing.

The IP theft is a real sore point and I wish that that Western countries would put more pressure on China to respect our patents and copyrights. I suppose that right now the desire among the rest of the world that China help rein in that nut job in NoKo is overshadowing everything else with regard to diplomacy with China.

Rich
 
No one has mentioned it, but don't forget to put anti-seize on the new plug. Galvanic corrosion is your enemy, good antiseize will help to mitigate some of its effects.
 
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