Stubborn Water Pump Bolt How to Break Loose?

[rzacc]

OK, NOW FOR THE FINALE....WHAT HAPPENED? Did you get it out??

 

[mgenecombs]

Stubborn Water Pump Bolt - How to Break Loose?

1981 Satoh Bull S-630 has badly leaking water pump seal and a new pump in in hand to replace. Only problem is that one of the through body bolts will not break free and I am worried if I apply any additional force the bolt will snap. Any advise on how to work on this successfully?

If you still haven't resolved your stubborn bolt issue, consider this:
Saw or grind the head off of the bolt. Once the head is gone you can then remove the pump. After the pump is off vise grips and penetrating oil should finish the job

 

[tcreeley]

Good quality hex wrenches are always the best to use. I put them on the bolt head (snug) and tap the end of the wrench handle lightly with a 3 lb hammer. or If the head of the bolt is still good - I'd use a torch to heat the head of the bolt to a red and while it is hot turn it with a wrench. Both work for me- torch is great for brakelines where the steel is so thin- it snaps easily with too much force. -Never had luck with penetrating oil.

If you do take the head off- don't use vice grips- useless (in my experience). Flatten/grind/file the left over bolt , center punch and drill a hole into the center of the bolt to use an "easy out".View attachment 352552

 

[Lane]

Thanks everyone! Finally got time to replace the pump today and got the bolt out undamaged and able to use again! After I removed the belt, alternator and belt guard I soaked the stubborn one down with PB blaster. I then ran the engine (without cooling water circulating) to heat the motor block up to where I could just still hold my hand on the block. A few raps with a mallet and then careful back and forth with a wrench, more PB blaster, more raps with pressure on the wrench and it broke free. Going put back together now with the new pump.

Glad to have this little 33 year old Bull running again. BTW, this is the first part I've had to change since I bought it new in 1981! Even has the original water hoses which are pliable and came off the pump with no problem. Wish they still made 'em like this!