Fly wheel won?t pull

Carl

Carl

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Well, got the flywheel bolt loose on my Merc 25, left the bolt on but backed it out about a 1/4?, put on a 3-point puller and cranked it tight but the flywheel won?t ?pop?. Sprayed some penetrating oil, tapped on it and the pulled bolt but not budging.
Other than let it sit with pressure on it, any advice?
 
Try using a little heat. Get it warm enough then spray WD40 where the shaft comes thru. That will help it loosen up some. Used to do that with brake lines that would not come. Keep the pressure on it with the puller on it
 
On flywheels i have had a lot of success without a puller by placing a large bar under the flywheel and pressing up on the flywheel. Then with the nut on but loose striking the top of the nut on the crank with a brass hammer or standard hammer very carefully not to mar the threads on the crank. The puller is the right way. You can also install the puller with tension pulling up then with a brass drift rod strike the crank if your puller allows this i use the type with a center hole. There is a few thousands play in the crank up and down which makes it possible. Do this at your own risk I'm just some guy with a computer.
 
Carl said:
Well, got the flywheel bolt loose on my Merc 25, left the bolt on but backed it out about a 1/4?, put on a 3-point puller and cranked it tight but the flywheel won?t ?pop?. Sprayed some penetrating oil, tapped on it and the pulled bolt but not budging.
Other than let it sit with pressure on it, any advice?
Click to expand...

Really hard to tell what's going on without just being there.
(A) not enough pressure generated by the puller,,,,, crank it down a bit more
(B) not enough impact from the hammer,,,,,,, needs more than a tap. Not sledgehammer worthy but more than a tap.
(C) three point puller,,,,,,,,,, using jaws or bolts to grab the flywheel. If bolts make sure you have sufficient thread depth into the flywheel to prevent stripping the bolt holes, BEFORE attempting A or B above.
(D) will the forcing screw on the puller pass thru the hole in the flywheel? If so remove the bolt and push directly on the end of the shaft. If not , just check to make sure you still have a gap between the bolt and the flywheel.

wish I could analyze the issue better. I would use heat as a last resort. Guess I start by making sure you have the 3 puller bolts deep enough into the flywheel , so those threads do not strip out. If using a jaw type puller, good to go. Then I'd increase the torque on the forcing screw, followed with a more authoritative blow with the hammer.

PS, If something breaks, not my fault. Doesn't that give you a warm fuzzy feeling?
 
Checked on it this morning after sitting all night under tension.
All three jaws still fully engaged and I was able to get about 1.5 more turns on the center bolt of the puller.
So maybe it loosened up a little.
 
Carl

Can you post a picture? Usually when I've had problems pulling parts apart it came down to the slightest amount of corrosion. This is especially the case when it is an aluminum part on a steel shaft. You may be battling corrosion and when it breaks loose you will hear a "POP" and all tension will be released. Heat is usually your friend under these circumstances, that and a whack from a small sledge and brass drift. Grab the old "blue wrench" and give it a try.

Eric
 
I meant to get a pic this morning but got in a hurry. I?ll post a few tonight.
 
Carl,
All kinds of video on YouTube for small engine flywheel puller. Might give you a better idea of how much force to use . FWIW I've never needed heat to free a flywheel.
 
Still stuck when I got home. Rain tomorrow so took off the puller and put the cowling back on. Will try again this weekend. Thanks for all the advice.
 
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