Wanting to change plugs in 6 cyl JD 55 combine.They are quite rusted,broke one,got it out and replaced.What can I do to make the other 5 easier?The engine runs,should I run it up quite warm and try again?
If you can get a socket and an impact on it, set the impact low and let it hammer away. I’ve removed a lot of broken studs by welding nuts on and have had more success getting them out with an impact than just using a wrench.Had to replace a plug on the morridge 400. Rusted solid. Put the impact on it and it come right out after a few seconds. I realize it's a little different situation as I had nothing to lose. But a good last resort maybe.
This is how I prefer to prep broken studs also, never had much luck going through the nut. Too much twist with the extra buildup to get that far up, or the nut fills with slag before it welds properly to the nutI like to weld a washer to the broken studs, then weld a nut to the washer around the perimeter of the nut. Easier than welding the inside of the nut and the extra heat helps to shrink the stud.
And repeat as necessary.Our FD restored a 1927 fire truck in my shop. To remove the plugs this is the order of events that need done:
1. Soak the crap out of them with penetrating fluid.
2. Drink mass quantities of beer afterward.
3. When all beer is gone and everyone is lit soak again. Take extra care to not involve any tools at this point.
4. Remove after hang over subsides.
Your results may vary.
I had a low pressure port on the clutch of a JD 8440 with an aluminum cap on it, the mechanic said I would likely twist the aluminum fitting off. I put a box end wrench on the cap and with light pressure on the wrench, tapped the cap, it came free.The heat, lube, and an impact. Tapping on a wrench with hammer can do wonders. Has more control than an impact. It is old, take your time.