Got the eccentric pulley bolt off. Took a 3/4” 18mm high impact socket, a 4’ 3/4” steel breaker bar, 1 4’ pipe extension on said breaker bar, a 4’ pipe extension on the flywheel 4’ ‘holding’ bar, and a backhoe to hold the flywheel bar down. The steel breaker bar deflected at least 4” on the shaft till the bolt popped loose. I thought it might break!

This is the worst I have found rebuilding several 13B engines. 

I didn’t have enough 1/2” air supply for the huge 3/4” IR air impact wrench I had, and doubt that would have worked. And it’s rated at 1225 ft lbs. 

M



Marc,

 

I found a torque wrench with 900 ft lbs of torque will get it off without having to wrestle a rotating engine block.  I struggled as you did and found this always worked for me.  A tool rental place should have one.  Works well on the flywheel nut as well.

 

Ed

 

------ Original Message ------

From "Marc Wiese cardmarc@charter.net" <flyrotary@lancaironline.net>

To "Rotary motors in aircraft" <flyrotary@lancaironline.net>

Date 3/20/2023 4:05:39 PM

Subject [FlyRotary] eccentric shaft pulley bolt removal

 

Fellows,

Been trying to tear down an extra FD engine and I’m having a devil of a time getting the front pulley eccentric bolt off. The flywheel nut has already been removed. I did put the counterweight and flywheel nut back on to be able to bolt a bar to the counterweight to keep the eccentric shaft from turning when trying to get the eccentric bolt off. Here is what I have tried so far: breaker bar extension pipe (+3’); propane torch on bolt for 2 min to break any sealant (?); impact wrench-nada; sledge hammer on breaker bar; solvent.

Nothing worked. The engine just lifts off the floor with more torque. Does it take a gorilla to get this nut off???

Any ideas how to get this dam bolt off?

M