So I'm in quite a pickle. I've got a very seized and heat-cycled water pump bolt that just wont come off. Every nut I weld to it just takes off more of the bolt. I'm getting down to my last bit of bolt before I'm going to be forced to pull the front cover to get more bolt to weld too. Is there anything else that I should be doing other than burning sage and preparing for an exorcism?

 

When I've had similar issues, soaking it overnight in Liquid Wrench and using a pair of Knipex Twin Grip pliers tends to do the trick.

Twin Grips: https://amzn.to/3Tm07FB

 

Agree with soaking, although I would go with AeroKroil - thinnest penetrant out there. Yes it is expensive, but will get in between spaces others won't Very rare for steel bolts in aluminum blocks to seize, but I had the same thing happen on an edelbrock intake recently. My Nasa buddy says it is galvanic corrosion. Have you rapped it axially with a hammer (don't do it too hard). If it budges at all when rotating, oscillate it in small movements until the range of motion increases.

 

It hasn't moved in the slightest. I'll soak it, give it a few taps, and see if that helps. I've also tried heating the block where the bolt enters to attempt to break it free with no luck. I'll update the post as things continue.

 

If I remember correctly, that bolt and the one below it go into the water passages in the block, so IMO, you are possibly fighting a losing battle. It is likely seized in the block because whoever replaced the water pump last didn't use thread sealant. I would guess the bottom of it is corroded and swelled past the threads in the water passage. If you try to back it out, it will likely remove the threads from the block, and the you'll be in an even bigger pickle. Your best option, again IMO, as crappy as it may be, may be to go ahead and remove the timing cover, and the drill it out in an effort to save what you can of the threads in the block. If you can drill it out carefully, you may be able to re-tap it to the original size. You won't likely be able the helicoil those threads, as they pass thru the block, although I guess you may be able to tap them to a bigger size, but then you'll be needing to clearance the water pump as well with the hopes it doesn't cause a leak from the pump. Regardless, I can't see any real good or easy options here...sorry for your predicament!

Although I just remembered I watched this video a while back... I've never tried it myself, but this guy uses some copper pipe and a welder to get seized bolts out of aluminum. Sounds weird, but if you watch this guys video, it'll make more sense...

 

if you can, carefully weld a threaded extension on (creating a stud). then use a nut to hold on the pump flange (rather than a bolt). Don't torque too much!

 

Got the same problem here. I tried to remove a water pump bolt that goes trough the front cover into the block. The bolt snapped and all other methods to turn it out failed. In theory I could just pull the front cover off, but the bolt is seized to it. I can wiggle the front cover a bit, but it doesn't come off. Will I have a better chance with Aerokroil? Should I drill the bolt out? Last resort is to destroy the front cover around that bolt.

 

I personally have always removed a water pump after running the engine for a few minutes to warm the block up. I've found 100% stone cold tends to snap em off.

 

A heat gun might do wonders. Maybe a torch but you need to be pretty careful.

 

I applied lots of WD40 and several heat cycles with a heat gun until I could turn the snapped bolt back and forth a bit with a vise grip. Increased the rotation step by step, unfortunately the stud for the AC bracket was in the way for the vise grip at a certain point. I unbolted my vise from my workbench and used that to grip the bolt. Finally I was able to turn it out all the way. And luckily there is no thread damage on the block, which was my biggest concern.

But what idiot came up with the idea to drill the hole #8 all the way through into the coolant passage? It will lead to corrosion, seized bolts and your cooling system might start to leak through that hole.