using impact wrench for removing spark plugs

[Donald]

Some of the spark plugs on the Ford engine in my snowcat seem to be rusted in. I have sprayed PB Blaster on them twice so far.

I am thinking its better to use my impact then a breaker bar?

 

[CharBaby]

Noooooo!
Undo them by hand ONLY! And use a socket and ratchet so you have a good feel of what's going on. Take your time!

Spray them again, run the engine, let the engine good down and then try to remove'em again. Don't let it defeat you. You can do it!

 

[bigt61]

Let them soak longer before you go down that road. A week or two anyway.

 

[supton]

Any good to run the motor, heat it up, and then keep trying as the motor cools down?

 

[Doog]

Give them a slight tug clockwise with the breaker. Sometimes tightening will break them loose. If not hit them with the impact. I have used my impact to get stubborn plugs out before.

https://www.youtube.com/watch?v=pqjeamobVdY

 

[accent2012]

Wouldn't it be better to try and remove them when the engine is hot and just turned off? Reasoning behind that is that the metal would have expanded and be a bit more ductile making it easier to remove the spark plugs.

After some googling, some people suggest you do something similar to that, like this...

http://www.practicalmachinist.com/vb/general/ot-dry-ice-remove-spark-plug-al-head-212404/

 

[Oldmoparguy1]

Originally Posted By: supton
Any good to run the motor, heat it up, and then keep trying as the motor cools down?


Yup. Heat it up, spray it, let it cool down. May take several tries. Try some home made atf based stuff. I got a stuck brake drum off with that.

Wayne

 

[Doog]

Here is the hot engine extraction method on an F-150..this guy is funny

https://www.youtube.com/watch?v=XOVhhkC3A2c

 

[Doog]

Originally Posted By: accent2012
Wouldn't it be better to try and remove them when the engine is hot and just turned off? Reasoning behind that is that the metal would have expanded and be a bit more ductile making it easier to remove the spark plugs.



Yes, that is the preferred method.

 

[Astro14]

Wouldn't use an impact....too easy to strip out the threads.

I would allow a good penetrating oil (I don't care for PB'laster, liquid wrench seems to work better for me) to soak for at least a day.

Then, if the heads are aluminum, then heating them up a bit will take advantage of differential expansion of dissimilar metals. Getting one of those products that freezes things, like Loctite's new Freeze (which I haven't tried...yet...), would further take advantage of that. Even in iron heads, warm heads and cold plugs will loosen the fit ever so slightly...

 

[neilLB7]

My 2003 trailblazer valve cover had plug removal instructions molded into it with BIG letters. DO NOT REMOVE SPARK PLUGS WHEN HOT.

Anyhow...I've always cracked them loose what I could cold...then shot Kroil down in the holes (such as on the trailblazer). Let it sit overnight and work them in and out. Tighten, loosen, tighten, loosen. With not too much force at all.

Problem with the trailblazer head for example is some of the threads on the bottom get carboned up and that will bind the plug up if you try to remove them on the first try.

It's a sinking feeling to watch threads come out with the plug. Also about 10 to 13 ft-lbs is all you need for an aluminum head. And use an old toothbrush to "dust" some never-seize on all the threads. Don't goop in on.

 

[Doog]

Note some of the guys doing the famous F-150 plugs do a seafoam treatment the day before to remove any carbon that may be binding them in there. You might try that first.

 

[Donald]

The engine is not running. I am removing the plugs to dump some oil down the cylinder before I start it for the first time ina long time.

 

[SwampSurvivor]

Plugs on an old cast iron head 300 six are a bit different than the three threaded spark plug holes on early Modular 5.4s.

I have changed spark plugs on warm/hot cast iron head engines before with no problem. Aluminum - won't touch unless stone cold.

Have you tried tapping the the end of the ratchet to aid with moving? Not hard, just small "jolts"? Also - try in both directions.

Whenever I remove plugs for the first time, I apply torque in both directions. Then, once they are broken loose, I will turn them back and fourth on the way out.

Heat / cool cycle wouldn't hurt - but since the engine isn't running that's not an option.

 

[SOHCman]

Use a 50/50 mix of acetone and ATF and give them a gooooood long soak. Is this engine iron head? I've been having a like situation changing the Plugs on my running 5.8. I just give them a squirt once in a while with an oiler when the engine is cooling down and will eventually try a tight fitting socket and breaker bar in a slow careful manor.

You could heat the head around the plug with a butane torch if its a iron head, wouldnt do that on aluminum.

 

[zzyzzx]

Originally Posted By: Donald
I am thinking its better to use my impact then a breaker bar?

And I would just try to restart it without adding the oil as you mentioned.

 

[datech]

Apply force in both directions after you get them broken free. Turn them out a bit, then turn back in just a little. Keep doing that until they turn out freely or they are all the way out.

 

[dlundblad]

When you talked about your snowcat, I thought you were referring to an Arctic Cat.. Do you have pics of this thing??

 

[Hyde244]

I have had success with a breaker bar in the past. I'll be swapping out my own plugs at 90,000 miles, and hope a WD-40/Breaker Bar combo will do the trick.

 

[440Magnum]

I'm amazed at the number of opinions against an impact, assuming this is an iron-headed Ford 300.

Personally, I WOULD use an impact (gently, in short bursts, and starting on the lowest air flow setting) before I'd tug on it with a breaker bar. If you have a small "butterfly" impact wrench, that would be the best option. I've broken FAR more parts with a breaker bar than I have with an impact wrench. Yes, its unnerving to realize you can't "feel" the part breaking loose, but you have to trust that short, sharp hammer-blow pulses of torque are simply less damaging than sustained high torque like you get from a breaker bar.

Of course all the suggestions for soaking with a mix of solvents are excellent and should be done first- but an iron head with iron plugs and a breaker bar- that's a recipe for disaster. An impact is far less likely to break a plug off in the head, IMO.

Note: if this were an aluminum-headed engine, then my recommendation would be to heat the plugs (gently) with a torch, then chill them quickly with a "freeze-it" type spray from an electronics repair shop. I wouldn't use *either* an impact or breaker bar on an aluminum head.