homemade thread chaser

[sgull]

I was experiencing what was seeming like some excessive resistance when trying to remove at least one of the four spark plugs from my '92 Accord. While unscrewing as it was becoming close to being out, it began getting tighter to turn. I did manage to finally slowly work it out by applying a little carb cleaner down close to the threaded part of the plug and turning back and forth slowly to break up the apparent carboned-up threads which I've been advised is likely the issue. Fairly certain there is no cross-threading going on, as I have managed okay to reinstall the plug without much problem. But still I'd like to go ahead and run a thread chaser into each spark plug hole in the head, particularly the one I noticed the unusual tightness I described above. I'd be trying to clear some of the build up carbon from those threads with the chaser. However, the design of the head on this car is such that the spark plug wells are too skinny to insert the typically available spark plug chasers like this:*@#$http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Spark-Plug-Thread-Chasers/_/R-SER730_0006401120*@#$which I've already attempted to use but can't because the hex size for the socket requires a 13/16” socket and that's too wide to fit into the hole; even a thin-walled socket is still too wide. So I came across this info in a forum where somebody was describing a homemade thread chaser for the job, which I would like to try: *@#$http://forum.miata.net/vb/showthread.php?p=6412358#post6412358

My question is in regard to the thickness of the metal cut-off disc for the angle grinder. The disc in the instruction specifies the use of an .045 (and shows a Norton brand disc) whereas in my location that size is unavailable at any local outlets. For my angle grinder the closest disc size to that is 4 1/2” x .045” x 7/8”. Of course that might seem like an insignificant difference but still I wouldn't mind some opinions/comments as to whether that could actually matter much, and maybe any input as to whether the homemade tool should do the job fine or not. I'm a little unclear as to what it is about thread chasers that make them work; what is it about the notch(es) that “chases” the threads. Plus, in the homemade one, I suppose I need to get that slant on cut just right across the threads too, and not sure how much luck I might have doing that.

 

[madison069]

the notch doesn't clean the threads, the threads of the chasers do the actual cleaning. The notches give the grime/carbon/rust somewhere to go instead of being pushed into the thread of the hole.

As long as you don't cut too much of the thread of the spark plug off and the threads do not have burrs in the thread then an old spark plug with notches can do the job once you put the notches on the plug.

 

[tdkkart]

I've done the same thing numerous times by simply using the corner of a file to make a similar groove in the threaded portion of a bolt or spark plug, works just fine.

 

[MattPersman]

I have done it to bolts spark plugs etx to make a quick chaser with a cutoff wheel

 

[Banjorear]

While putting the new plugs back in, make sure you use some thread dope or anti-seize. I would use the copper type. Sounds like that thread is getting weak. Last thing you need is to strip out a spark plug hole. Major hassle.

 

[aka Larry]

While putting the new plugs back in, make sure you use some thread dope or anti-seize. I would use the copper type. Sounds like that thread is getting weak. Last thing you need is to strip out a spark plug hole. Major hassle.

X2. I always use anti-seize on spark plugs.

 

[sgull]

Okay thanks for the replies. Guess I'll give it a try with my .045 thickness disc then. Gotta get that slant just right, just like in the picture I would presume.

In regard to using anti-seize, seems for various reasons there is a big differing of opinion on whether that's a good idea, but I don't wanna open that can of worms right now. I do happen to have some copper type anti-seize; I'll probably go ahead and use a little dab, regardless. Thanks again

 

[rslaback]

You do also have the option of just using an M14x1.25 tap.

 

[signcrafter]

You do also have the option of just using an M14x1.25 tap.

Personally I would not use a regular tap in a spark plug hole, you want to use a thread chaser. Taps can cut new threads where as chasers just reform the threads.

Lisle does make a tight access spark plug chaser in a few different sizes, http://www.amazon.com/dp/B008MFR2IS/?tag=atomicindus08-20. I have the main ones for spark plugs and you just use a 3/8" drive extension with them. Work great for situations like the OP's.

 

[sgull]

You do also have the option of just using an M14x1.25 tap.

The plug wells are pretty deep, I think it is like six inches down. Not sure if I had a tap how I'd attach it to whatever to keep from losing it down in there. My regular 5/8" spark plug socket (on the end of an 8" ratchet extension) seems to grip the spark plugs easily so that's another reason I'm thinking the homemade chaser could work out for me. Plus, I think I chaser treatment on the threads is more what they need, not necessarily a tap, unless a tap would indeed work just as well (if I had one and knew how to keep it attached/secure).

Still no comments/responses in regard to the apparent slant I need to get right on my homemade chaser? Doesn't matter much, just eyeball/freelance it best I can with my cut-off disc?

 

[Fcvapor05]

You do also have the option of just using an M14x1.25 tap.

If want to dump shavings all over the piston, sure, that's an option.

 

[sgull]

If want to dump shavings all over the piston, sure, that's an option.

Yeah, think I'll steer toward the chaser idea instead.

 

[sgull]

Lisle does make a tight access spark plug chaser in a few different sizes, http://www.amazon.com/dp/B008MFR2IS/?tag=atomicindus08-20. I have the main ones for spark plugs and you just use a 3/8" drive extension with them. Work great for situations like the OP's.

Ah. There's the ticket then. The two local parts places in my community just have that other type I linked in my first post. They could probably/maybe order me the one as described in the quote above, but hey I'll just go with Amazon probably cheaper that way anyhoo.
Thanks

 

[madison069]

the slant don't matter, as I said it's just a place to let the grime come out of the threads easier.

Another tip is to put a dab of grease in the slots to catch the grime instead of letting it fall into the cylinders.

 

[rslaback]

If want to dump shavings all over the piston, sure, that's an option.

A) If there is only carbon build up like the OP stated then there wouldn't be any, just carbon which he is going to dump into the piston anyway.

B) That issue is easily taken care of by smothering the tap in grease. The grease fills the flutes and holds the swarf.

 

[Zeke]

Either way use a heavy oil or light grease to capture any shavings. Use the anti seize but wipe the seat clean. You don't need any electrical interference. Just use a Q-Tip and lightly coat the first 3 threads all the way around. Use another Q-Tip to wipe the seating surface with cleaner, any cleaner. Clean the hole too. A little bottle brush should do it. Invariably you are going to get a small amount of crud in your cylinders. I'd rather have a few crumbs in the cylinder than a galled plug thread.

 

[sgull]

the slant don't matter, as I said it's just a place to let the grime come out of the threads easier. Another tip is to put a dab of grease in the slots to catch the grime instead of letting it fall into the cylinders.

Thanks, will do.

 

[sgull]

Either way use a heavy oil or light grease to capture any shavings. Use the anti seize but wipe the seat clean. You don't need any electrical interference. Just use a Q-Tip and lightly coat the first 3 threads all the way around. Use another Q-Tip to wipe the seating surface with cleaner, any cleaner. Clean the hole too. A little bottle brush should do it. Invariably you are going to get a small amount of crud in your cylinders. I'd rather have a few crumbs in the cylinder than a galled plug thread.

Thanks. Good tips, so I can do it up proper.

 

[sgull]

Also, look what I found. Things are looking brighter (cheaper) if decide I really want that doohickey. http://www.ebay.com/itm/Lisle-20020...1493464891&pt=Motors_Automotive_Tools&vxp=mtr

Will maybe go ahead and maybe at least try the homemade one though, not much to lose I suppose. Unless ya'll think I'd be better off with that limited access chaser, and not waste my time with the homemade one.

 

[y20dth]

As been said above:
- the angle/slant does not matter that much. The cut is just there so shavings/chips/carbon has a place to collect and does not get jammed between the threads.
- put some grease on the thread chaser so the junk sticks to it, and does not fall in the combustion chamber.

I just found this text in the link on that forum:
"How do you prevent the metal shavings from dropping in the cylinder when you do this?
If there were any, they're just aluminum. They wouldn't hurt anything, and be just blown out or vaporized out in short order after the engine start."

This statement is absolute BS. As always, the internet houses some wisdom, and a LOT of ****....

 

[sgull]

As been said above: - the angle/slant does not matter that much. The cut is just there so shavings/chips/carbon has a place to collect and does not get jammed between the threads. - put some grease on the thread chaser so the junk sticks to it, and does not fall in the combustion chamber. I just found this text in the link on that forum: "How do you prevent the metal shavings from dropping in the cylinder when you do this?" "If there were any, they're just aluminum. They wouldn't hurt anything, and be just blown out or vaporized out in short order after the engine start." This statement is absolute BS. As always, the internet houses some wisdom, and a LOT of ****....

Thanks for those additional helpful comments^. Yeah I saw that question/answer too and had been wondering BS or not. I'll put a little grease in the thread chaser slots.

 

[sgull]

Use another Q-Tip to wipe the seating surface with cleaner, any cleaner. Clean the hole too. A little bottle brush should do it. Invariably you are going to get a small amount of crud in your cylinders. I'd rather have a few crumbs in the cylinder than a galled plug thread.

Kind of almost impossible (or if possible, tricky) to be able to get a Q-Tip down there to wipe the seating surface with cleaner because the Accord engine has the deep recessed spark plug access situation where the plugs are down a good six or seven inches it seems from the top of the engine (need fairly long extension on socket to reach). And if you're lucky with a flashlight you can kind of see down in there okay but not very good really. So any suggestions in that regard would be appreciated.

Also in regard to cleaning the hole with a maybe a little bottle brush (per suggestion also quoted above): Same general situation/question how might I be able to get down in there very good with a bottle brush to clean the hole(s). Seems like I'd need just the right type/style of bottle brush, if there is one, with a long enough handle that would reach the hole(s) and be stiff enough for me to try to manipulate back and forth from above.

 

[sgull]

Still hoping for any comment/suggestions in regard to my previous post here.

(Ah, maybe never mind. I need to probably get my hands on something like this: http://www.northernautoparts.com/part/bl-spb )

 

[sgull]

Another tip is to put a dab of grease in the slots to catch the grime instead of letting it fall into the cylinders.

How much of a "dab" works best? The (three) slots in the chaser I bought are fairly deep. Should I pretty much pack/fill the grease into each slot, or just try to fill the slots halfway or so full of the dab of grease? Also, I have some regular wheel bearing grease; will that kind of grease be just fine to use. Also, does the little bit of grease that might get into the threads in the spark plug hole(s) cause any problem or conflict with the little dab of anti-seize compound I'll be applying onto the spark plug threads themselves?

 

[Jagmandave]

You're overthinking this job, just run the thing down the hole and if you're worried about the dirt, use your air gun to blow the stuff back out.

I would not use grease, dry carbon will blow right back out the spark plug hole. Just stick a piece of rubber or plastic tubing to the end of your blow gun and stick that down into the plug hole, wear safety glasses and maybe put a shop towel over the end of the plug tube to catch the worst of the schmutz.

Job done. Antisieze won't keep the ends of the plugs from carboning up - I always put new plugs in clean and dry and I've never had one gall yet in 30+ years of fixing cars.

I also just use spray penetrant - like you'd use on a rusty bolt - when they come out hard, then blow it clean again.

 

[sgull]

You're overthinking this job, just run the thing down the hole and if you're worried about the dirt, use your air gun to blow the stuff back out. I would not use grease, dry carbon will blow right back out the spark plug hole. Just stick a piece of rubber or plastic tubing to the end of your blow gun and stick that down into the plug hole, wear safety glasses and maybe put a shop towel over the end of the plug tube to catch the worst of the schmutz. Job done. Antisieze won't keep the ends of the plugs from carboning up - I always put new plugs in clean and dry and I've never had one gall yet in 30+ years of fixing cars. I also just use spray penetrant - like you'd use on a rusty bolt - when they come out hard, then blow it clean again.

Yeah thanks for that reply Jagmandave. Makes sense to me to just do what you say, not bother with using grease on the chaser, and just blow any loose dry carbon flakes/particles or whatever right back out the spark plug hole with an air gun. I'll do just as you suggest in that regard.
In regard to whether to use any anti-seize, your comment how that doesn't keep the ends of the plug from carboning up also would be true and is a good point here. Seems to be those that insist on always using anti-seize on plug threads, and those like yourself who never bother with that extra little task and do just fine. Probably won't even be much if any dirt or loose carbon that even blows back out anyway. In my particular case this time, I've already cleaned out the plug holes pretty darn good with a little carb cleaner and a bottle brush, and have also cleaned the seats off pretty good too (per Zekes recommendation this thread). I am going ahead next and use the little chaser tool like this one which I bought: http://www.amazon.com/dp/B000XF0P5M/?tag=atomicindus08-20 just to help clear/clean the the threads all the better before installing a set of new clean dry plugs. I notice even the directions that come printed on the chaser package mention "important: use anti-seize", but, you know, I think I just won't bother with that and quit all this overthinking and just be done with it like ya say. Thanks man.

 

[T45]

How much of a "dab" works best? The (three) slots in the chaser I bought are fairly deep. Should I pretty much pack/fill the grease into each slot, or just try to fill the slots halfway or so full of the dab of grease? Also, I have some regular wheel bearing grease; will that kind of grease be just fine to use. Also, does the little bit of grease that might get into the threads in the spark plug hole(s) cause any problem or conflict with the little dab of anti-seize compound I'll be applying onto the spark plug threads themselves?

If you are worries about load of thread coming out you've got other issues.

just a very light amount of grease if any. Two stroke oil might be something to consider.

those grooves are to collect the **** in the threads.

there shouldn't be anything in the plug hole except carbon and anti-seize-residue

if there is metal you are looking at a re-threading project.

sure you know this just re-stating this for context, but chasers only clean out soft material, and they straighten skewed threads

they don't repair any damage.

as for anti-seize/ grease, neither are a good idea to put into the cylinder bore.

I'd personally chase the chaser with a q-tip and some contct cleaner

As bare metal is a better starting point for the re-inserted plug (even if you use anti-seize), IMHO

 

[sgull]

If you are worries about load of thread coming out you've got other issues.

I'm not worried at all about a load of thread coming out. Fortunately do not have such issue.

just a very light amount of grease if any. Two stroke oil might be something to consider.

Ok. I get it.

those grooves are to collect the **** in the threads.

That's what I understand. And I guess the idea of putting grease in the grooves is to catch any "shavings", but I don't expect much in the way of anything except soft shavings/particles and not that much at that.

there shouldn't be anything in the plug hole except carbon and anti-seize-residue. if there is metal you are looking at a re-threading project. sure you know this just re-stating this for context, but chasers only clean out soft material, and they straighten skewed threads they don't repair any damage.

Yeah at worse I have a might skewed thread or two.

as for anti-seize/ grease, neither are a good idea to put into the cylinder bore.

Seems like just a little dab carefully/minimally applied just to a few plug threads wouldn't cause harm, but I'm not gonna bother with either anyhoo.

I'd personally chase the chaser with a q-tip and some contct cleaner

I have some good and fairly fat-headed long-handled q-tips I can use to do that. What do you mean contact cleaner? Like electrical contact cleaner?

As bare metal is a better starting point for the re-inserted plug (even if you use anti-seize), IMHO

I think I'd tend to agree there.

 

[T45]

Make sure to lubricate the chaser. You need something -- don't do it dry -- research what your block is made of and pick the right stuff. Personally would take into account manufacturers recomendation and also google a second opinion. Again, just enough, not so much as to contaminate the chamber. If you feel it binding, can do it in stages, no worries. Chaser will physically remove most of the gunk, and it mostly shoud cling to the chaser, and the solvent shoudl just be to remove the lubricant-film.

Recommend to use the least harsh chemistry to clean the threads. Generally that's not brake cleaner or Carb Cleaner. Also, keep it all out of the motor. Doesn't play nice with (piston, ring, valve) coatings. I'm sure you get the idea.

Use some tape in the threads a mic to confirm the max thread depth from the pulled plug. Basically just don't force it at the end.

Hope this is helpful.

 

[sgull]

Make sure to lubricate the chaser. You need something -- don't do it dry -- research what your block is made of and pick the right stuff. Personally would take into account manufacturers recomendation and also google a second opinion. Again, just enough, not so much as to contaminate the chamber. If you feel it binding, can do it in stages, no worries. Chaser will physically remove most of the gunk, and it mostly shoud cling to the chaser, and the solvent shoudl just be to remove the lubricant-film. Recommend to use the least harsh chemistry to clean the threads. Generally that's not brake cleaner or Carb Cleaner. Also, keep it all out of the motor. Doesn't play nice with (piston, ring, valve) coatings. I'm sure you get the idea. Use some tape in the threads a mic to confirm the max thread depth from the pulled plug. Basically just don't force it at the end.Hope this is helpful.

Okay I'll lubricate the chaser with at least a few drops of oil. I'm fairly certain the engine block on this '92 Accord is aluminum, but haven't a clue (until I might be able to find out for sure somehow) what would be the ideal type of oil to use for that. I do know my repair manual for the vehicle does state to "lubricate the threads of the spark plugs with a drop of oil or anti-seize compound." I already used a little carb cleaner as I mentioned with a bottle brush in the block threads, so too late for me to follow the advice on not to use that. I didn't use much, just did sparingly, so hopefully no harm done there. Also, I'll be very careful not to run the chaser down to any lower threaded depth than that of an installed plug thread depth. Thanks for your comments/advice.

Edit: Since posting I came across the following info in regard to NGK spark plugs, which are the brand I have: "All NGK spark plugs are manufactured with a special trivalent Zinc-chromate shell plating that is designed to prevent both corrosion and seizure to the cylinder head; thus eliminating the need for any thread compounds or lubricants on initial installation." So I know I won't be using any lubricant or anti-seize on the spark plug threads. Just the chaser a little, though, as per advice in post quoted above.