Removing Generator Head: 5kW Coleman Powermate

[AUEngineer]

I have tried everything I've read in this forum to remove a coleman powermate 5000 generator rotor from a 10HP tapered shaft Briggs.

Pulled end and stator of generator off--left with engine and rotor hanging off crankshaft. Removed long 6.75" rotor bolt.

1) I first tried the hydraulic method. Set engine with shaft up vertical (after draining the oil of course). Tapped end of rotor with 3/8 standard thread. Filled rotor shaft with 10W30. Applied teflon tape to bolt, threaded in, and turned. Oil was squeezed out around base and came out on plastic fan shround. Repeated a couple times, with no success.

2) Fill rotor shaft with penetrating oil. Spray penetrating (PB Blaster) around the base as best as possible. Let sit for 30 mins. Wack the laminations with dead blow hammer--hard!! Turn 180 degrees, smack it again and continue. Turn 180 and hit it some more. Continue for 30 mins until exhausted--not a budge.

3) I then cut off the 5/16 threaded rotor bolt so it's long enough to be used as a push rod. Cut screw driver slot in end of 5/16 rotor bolt and use small flat head to engage the bolt/push rod in the crank shaft threads. Used freshly made 3/8 threads from step 1 to thread 3/8 bolt in the end of rotor shaft to push on newly fabricated push rod. Firmed up tight! Wack with dead blow hammer some more, and some more, and some more. Try to tighten bolt--still tight. Remove everything, more penetrating oil, reassemble setup. Tried some more. No success.

4) Use impact to tighten 3/8 bolt, very tight! Bang some more with dead blow hammer. Tighten some more with impact. Bang some more. Tighten some more, and, as you would guess, I have now stripped the 3/8" threads I made.

I'm completely frustrated. Absolutely no idea what to try now. At this point, I'd consider sacrificing the rotor, just to get it off the engine!

Any fresh ideas or suggestions would be greatly appreciated!! Help!

[roym]

I use step 3, a long screw pinch bar applies pressure to the back end of the rotor while the tapometer judiciously assails the bolt. Be careful not to damage the windings.

[declid]

ive used step #1 but use grease and use a impact wrench to squeese, if it doesnt pop smack bolt quick with heavy hammer... tom

[MARLIN]

I
2) Fill rotor shaft with penetrating oil. Spray penetrating (PB Blaster) around the base as best as possible. Let sit for 30 mins. Wack the laminations with dead blow hammer--hard!! Turn 180 degrees, smack it again and continue. Turn 180 and hit it some more. Continue for 30 mins until exhausted--not a budge.

Help!

put the long bolt back in,a couple of threads. so rotor wont fall out, then with a 5 lb or 8 lb and a piece of 2x4. give it a shot or two.it will pop loose.

[AUEngineer]

I
2) Fill rotor shaft with penetrating oil. Spray penetrating (PB Blaster) around the base as best as possible. Let sit for 30 mins. Wack the laminations with dead blow hammer--hard!! Turn 180 degrees, smack it again and continue. Turn 180 and hit it some more. Continue for 30 mins until exhausted--not a budge.

Help!

put the long bolt back in,a couple of threads. so rotor wont fall out, then with a 5 lb or 8 lb and a piece of 2x4. give it a shot or two.it will pop loose.

Okay, sounds like the suggestion here is more umphf!
8lb hammer -- check
2x4 -- check
Where should I place and how should I position the 2x4 before applying the convincing blow(s)?

[MARLIN]

on the laminations, just a quick shot or two. then other side.

[Arkie]

You previously wrote this in your first post:
1) I first tried the hydraulic method. Set engine with shaft up vertical (after draining the oil of course). Tapped end of rotor with 3/8 standard thread. Filled rotor shaft with 10W30. Applied teflon tape to bolt, threaded in, and turned. Oil was squeezed out around base and came out on plastic fan shround. Repeated a couple times, with no success.

Are you saying the oil squeezed out at the tapered crankshaft end by the engine?

[AUEngineer]

Are you saying the oil squeezed out at the tapered crankshaft end by the engine?

Yes... that's exactly what happened! After I fill the rotor shaft with PB Blaster, it too leaks out at the tapered end by the engine as well--with no force behind it.

I'm at a total loss. Hung the engine by all thread threaded into the rotor end to keep constant pressure on it. Put padding below engine, and only hung about 1" above the padding. Beat and banged on the laminations with dead blow hammer, hit on the all thread top with 5# hammer, even resorted to picking up the board and dropping the entire thing about 6 inches on the saw horses repeatedly! Still won't break loose. See the image below.

At this point, I'm thinking I should be finding a way just to get the rotor off to salvage the engine. Any ideas? I'm wondering if the person who had this before me installed lock-tite or some other adhesive???

Anyone know of a good way of applying heat to the taper? Can't get to the tapered shaft because the generator housing bolted to the engine is in the way.
Plastic cooling flywheel looking fan is on the rotor closest to the taper, preventing access from the front.

Maybe serious vibration would do the trick? Any ideas here?

These things don't usually get the best of me, but I am completely out of ideas.

[Arkie]

Oil coming out at the end indicates maybe threads or a keyed shaft, but that would not OEM.???(oil coming out is not normal for a tapered shaft)

Try locking the engine and see if the rotor will wiggle or vice/versa. (lock rotor and rock engine)
I'm thinking if threaded and the crank driving the rotor CW when looking @ engine from rotor end the threads might be left handed or turn the rotor ccw with the engine locked for left hand threads. Might even try using or making a strap wrench.

Strap wrench can be made by wrapping the rotor several times with a nylon strap from a ratched strap and then a lever bar, maybe or lock the rotor with a strap and use strap on engine flywheel using a lever bar, maybe.

Suspect non standard coupling.

Was the generator section any good or are you just wanting the engine, trying to repair the engine or what?
Them rotors are pricy to replace is why I'm asking? (rotor may even be obselete)

[AUEngineer]

Strap wrench can be made by wrapping the rotor several times with a nylon strap from a ratched strap and then a lever bar, maybe or lock the rotor with a strap and use strap on engine flywheel using a lever bar, maybe.

I have access to a large strap wrench. Suggestions for the best way to lock the engine (or the rotor)?

Suspect non standard coupling.

I wouldn't think this is likely, as the prior owner took this alternator off another briggs and installed on this briggs, but I cannot say it's impossible.
However, given the difficulty I'm having, I'm hoping you are correct!

Was the generator section any good or are you just wanting the engine, trying to repair the engine or what?
Them rotors are pricy to replace is why I'm asking? (rotor may even be obselete)

I'm trying to get into the engine to repair the governor. I see these rotors can cost $200 - $300 if you can even find them. I've already slightly cracked the end plate on the rotor--somehow in the midst of hammering and banging--though I think that is repairable at this point. Any recommended sources/part houses for these type rotors if I destroy this one?

Thank you for everyone's input--should be back with another update later tonight.