Thread: Seized bolt

Hey folks,

I'm taking the water housing off a 300tdi engine and one of the long bolts that go through the water pump then water housing then into the block is seized in the water housing.
I cut the head off the bolt, to removed the water pump hoping that it was seized in the block and could heat/wd40 etc and vice grip it out but it turns out it is seized in the water housing as the water housing can wobble back and forth a bit on the block but the bolt moves only with the water housing... yay
Anyway, i have heated the housing with propane (dont want to heat alloy too much) and no luck. Soaked the bolt with wd40 with no luck, tried to hit the housing from behind to slide it off the bolt with no luck. Heated the bolt and let it cool trying to break up the corrosion with no luck. I think there must be a good 50mm of corrosion inside the casing bolt hole holding the bolt.

Any ideas what to try?

As a last last resort i could use a cutting disk and cut through the alloy housing (ruining it) leaving 10mm or so of the bolt sticking out of the block and then remove it. I fear that the bolt is snapped off only a few threads into the block anyway but that is another problem to fix once i get the housing off...

As with everything for my landy - this was meant to be a quick easy job!

Originally Posted by Johndoe

Weld a nut on the end of it.
The weld should give enough heat to break it free and the nut a good place to undo it.
Worked for me a gazillion times.

I tried welding too. The bolt was that stuck it kept shearing the bolt of a few mm when i tried to undo it.

I ended up getting some wood and using that and a big hammer to slowly, millimeter by millimeter knock the housing from behind off the bolt. It was properly seized almost the entire width of the casing, but it is all off now and thankfully the threads in the block are perfect! PHEW