Rusted exhaust manifold

freddmc

freddmc

Forum Newbie
I have a cooler command engine and want to remove the exhaust manifold, but the nuts on the studs are rusted quite severely. I’ve tried penetrate and that isn’t working. Is there a way to remove them without damaging the head? I seem to recall using an acetylene torch to heat the nuts, but not sure if this will damage the head or not

Regards,

Fred.
 
Let the nuts soak for a couple of days, then before you try to back them off actually barely tweak them tighter. This will break rust in the threads. Use a good fitting wrench or 6-point socket to break them loose and keep working back and forth a little at a time and keep spraying them as you go.

For future reference: Buy some Acetone and regular transmission fluid (no particular brand) Mix them 50/50 and then put the mix into a metal pressure sprayer (only mix enough to fill the sprayer when needed) and Wala! You will have the ideal rust penetrant for stubborn bolts and nuts.

I keep this stuff ready to use in my shop and only use commercial stuff to keep in my service truck.
 
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freddmc said:
I’ve tried penetrate and that isn’t working
Click to expand...
Because they don't work, as you found. Stop buying said products.
freddmc said:
Is there a way to remove them without damaging the head?
Click to expand...
Propane torch and candle wax. Put some good heat on the nut. Rub a candle over the threaded area where the wax can possibly get into the threads. Do this several times. Use a HAND ratchet or wrench to attempt nut removal. Tighten a bit then loosen a bit. Keep rocking the nut. If you get nut movement, do the wax trick again.

OR propane torch again. Nut good and hot. Spray cold water to shock the rust away. Should have a fat plume of steam when you hit with water. Nut should turn gray. Work it with a wrench.
 
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In order
Real penetrating oil such as Liquid Wrench, Kroil, Knock er loose, PB Blaster and not generic oil or WD40 spray. WD40 does make a penetrating oil however
Heat the area and nut up red hot with a torch, that may help. If it is a stud, heat the head until it is toasty but don't melt anything.
Grind it off so you have a stud to grab onto, if the stud breaks at the head, you will have to drill it out. The two above are preferable to cutting.
 
sgkent said:
In order
Real penetrating oil such as Liquid Wrench, Kroil, Knock er loose, PB Blaster and not generic oil or WD40 spray. WD40 does make a penetrating oil however
Heat the area and nut up red hot with a torch, that may help. If it is a stud, heat the head until it is toasty but don't melt anything.
Grind it off so you have a stud to grab onto, if the stud breaks at the head, you will have to drill it out. The two above are preferable to cutting.
Click to expand...
May have to weld nuts on to remove the existing nuts.
 
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