Can't get the plugs out

[k9sicem]

I decided to do a tune up on the Farmall C I just got. I changed the oil. It was black and thick. Looks like it had not been changed in years. As I was waiting for the oil to drain I started to change the plugs, I cannot get two of the spark plugs out. The two I did get out were very rusty. Here is what I have tried so far. WD 40, put on two times a day for four days. Running the tractor until it reaches temp, spray with WD40. Let cool and do it again. I've try using a breaker bar, and an impact wrench. Two of them just will not budge. I have tried this on both a hot engine and cold. Any ideas without damaging the plug treads?

[Winfield Dave]

WD 40, put on two times a day for four days.

Try substituting Kroil...worked for me.

[dgrapes59]

I would use penetrating oil like PB Blaster or Kroil, the WD 40 is a lubrication or water dispersion at best. Follow same regiment with the penetrating oil as you did with the WD 40 and you should have better results.

Good luck,

[Steve K. CALIF]

Turn them the other way....just kidding!!! Kroil might do it, like Dave suggested.

[Jim Becker]

I doubt that any kind of penetrating oil will get past the spark plug gasket. I would put the impact wrench back on and keep rattling them for a while. If they break rather than unscrew, you will then have to drill them out. You probably won't hurt the threads. The only way you will get any penetrant into the threads is by removing the head and going after them frm the other side.

Are they the proper spark plugs or did somebody put in plugs with too long a reach? If so, that may damage the threads.

[k9sicem]

They are Champion D-21 plugs. I think they have be in the the tractor a long time. The tractor looks like it has alway set out side . The tractor ran before I changed the oil and removed any of the plugs. After I changed the two I could get out of the tractor it still started right up and ran fine.

[John *.?-!.* cub owner]

to what Jim said.

[Winfield Dave]

After I changed the two I could get out of the tractor it still started right up and ran fine.

If it runs fine, I would keep Kroil-ing the 2 stubborn ones and occasionally put a wrench on them and try to loosen them.

[Barnyard]

If it runs fine, I would keep Kroil-ing the 2 stubborn ones and occasionally put a wrench on them and try to loosen them.

I doubt that any kind of penetrating oil will get past the spark plug gasket. I would put the impact wrench back on and keep rattling them for a while.

At this point I wouldn't want to waste my time or the Kroil. Rattlin' them sounds like it would be the cure, if you have an impact or access to one.

[Boss Hog]

If you use an impact wrench turn the air down a bit. They will ring off

[Rudi]

I think it was John that posted a few years back about the Butterfly Impact wrench. That puppy really is the cat's paw for getting stubborn bolts/plugs loose. What is nice about the Butterfly is that it has a built-in regulator some with up to 8 speed settings. Unlike the bigger impact wrenchs this one seems to just rattle things until they loosen with out fear of breaking them...... it is perception I think, but to my mind what ever works...

3/8" Drive 75 Ft. Lbs. Torque Compact Air Impact Wrench



One of my better tool purchases from Princess Auto

And as was mentioned.. I do not know why WD-40 is lumped in with Penetrating Oils because that is the very last thing one should try to use WD-40 for. WD-40 stands for "Water Displacement - 40th Attempt" .. it took em 40 trys to get it right. It does displace water quite well when used according to the manufacturers directions. I kinda enjoyed the Myths Legends and Fun Facts page.

[artc]

if you heat the plugs with a small torch like a plumbers torch while the motor is cold it will heat and expand the plug. when it cools it will generally have broken the bond with the rust and allow removal. if not repeat. a little kroil while its hot might help suck it in the threads.

you can't heat the block because there is too much mass so heat the small part to expand it in the hole. when it contracts again it will come out.

you'll be amazed.

[k9sicem]

Soak, heat, rattle with impact, soak, heat rattle with impact, repeat, repeat, repeat for seven straight days. Finally last night the plugs came out. The old plugs looked great. But I still put new plugs in with plenty of anti-sease on the treads.

[artc]

cool, thanks for the update

[CKCowboy]

Success is always sweet, looks like all of the advice given worked once again.
What a great bunch of guys here on Farmal Cub.com