Stuck flywheel

[waverly23]

1992 evinrude 15hp. Need to remove flywheel for ignition repair. For the last 4 weeks I've been trying everything the forums suggest. Yes, nut IS removed. 1/4-20 three bolt gear puller stripped the threads. Retapped to next larger size...stripped threads. Tried heat, tapping, patience etc. nothing helped. Everything that was supposed to help on the forums was tried without success. Today I bought Harbor Freights largest hydraulic 3 jaw puller. After difficulty of attaching, because of its large size, still would not move. Although I did not load the puller to its full capacity (12 tons) it was stressed very high. Once I got nervous about exploding and flying puller parts I gave up. This little motor ran perfectly last time out and I would hate to lose it for this problems. Can anyone suggest a different approach. Or at least tell me what might be going on preventing this flywheel from coming off.

 

[racerone]

Using the hydraulic puller is a mistake.---Who suggested using that !----------------------The three bolt puller is the only correct method.-------It requires a hefty bump from a hamer to release the locking tapers.--------If the motor ran perfectly then why do you want to take the flywheel off ???

 

[Bosunsmate]

heat and heat again the inside of the flywheel, not the crankshaft,
tap in wider bolt holes and thread the bolts right down, but not into stator
then with puller on tight whack the top of the puller with a small sledge hammer

otherwise as racerone says, why are you taking it apart, put nut back on and try and forget about it

 

[Tim Frank]

If it ain't broke....

 

[waverly23]

While converting my kicker from remote back to tiller I somehow damaged the throttle cam on the ignition plate. As a result I need to remove the flywheel to replace the cam. I've tried three times to use the correct method (harmonic balancer type puller) to remove the flywheel without success. Started with the pre drilled 1/4-20 high strength bolts, Retapped to 5/16, and finally to 3/8. All ripped out. Tried the tighten,, wack, and walk away approach for a week without success. Tried heating flywheel (not driveshaft) retightening, wacking and waiting and still no success. I was putting so much pressure on the puller that it was becoming almost impossible to hold the flywheel from turning with my strap wrench. I went to the 3 jaw puller just wanting to get the darn thing off even if I damaged the flywheel. It can be replaced.

 

[oldcatamount]

I'd suggest screwing the bolt back on a few threads because when that baby lets go, it may fly! Were you applying pressure at the same time using the heat? Don't be timid with the hammer.

 

[racerone]

The center bolt on the puller must be tightened to 80 FT-LBS or so then given a good bump with a hefty hammer.----Works all the time !!

 

[pro-crastinator]

Mine was a bugger as well. Keep top nut on top of flywheel - loose. Put flywheel under tension with the puller, sprayed pb stuff, tapped with hammer, Applied heat w heat gun, Left overnight, prayed, tapped with hammer next day, I went inside, came back out and Damn thing scared the crap outta me when it released. I was tapping LIGHTLY on outer "bell" of flywheel - which everybody says NOT TO DO. (so it is not warped or bent) Be SURE the top nut is on the shaft so it keeps flywheel from becoming a projectile.
I would say that patience will be the most important part of this task. - and perseverance!
good luck

 

[AlTn]

here's a direct quote from an Evinrude service manual 1978 9.9/15 hp page 4-19 , " NOTE The flywheel may not "pop" from the crankshaft taper when tightening the puller bolt. To "pop" the flywheel, use a heavy plastic mallet and tap the top outside diameter of the flywheel or puller. Do not hit the center bolt to remove the flywheel."
I realize this is contra to the method endorsed by many on the forum < striking the puller bolt with a hammer while the f/w is under tension >. I don't have a plastic mallet but use a piece of a 2x4 instead and strike it with a 2 lb. ball peen hammer. This is done on the outside diameter of the f/w striking down while the f/w is under tension. I turn the f/w in a clockwise motion a few inches at a time and whack it. Sometimes you need to tighten the puller after going around the f/w a revolution or so.
Good Luck!

 

[waverly23]

I have now tried every recommendation provided in this forum. I have now destroyed both under sides of my flywheel by alternating the left and right side with a 5# hand sledge. Trying to force the flywheel up and off the drive shaft. It's obvious that this F/W is caught. Are there any ideas that will work on this non standard "stuck flywheel"?

 

[Tim Frank]

Are there any ideas that will work on this non standard "stuck flywheel"?

Yes. Take it to a professional.

At some point, as Clint Eastwood said, "a man has to know his limitations."
No shame in that.

If you are bound and determined to DIY, I needed, once upon a time,to get a F/W off a small 4 stroke winch engine....it lived on the back deck of a trawler....salt water environment. Tried everything, but no go.

Last ditch gamble, I supported the bottom rim of the FW on an anvil, and hit the top rim , 180 deg. opp. , with a 6# sledge.....as sharp a blow as I could manage. Cracked in two....including the centre bore. No transfer of impact to the crank.

Your results may vary, and this is not what I would recommend; but in my case I had zero other options.

 

[waverly23]

I've always had the opinion that if someone else could do it...so could I. If I thought a pro had a different process than all the ones I've tried, I would take it to him. But I think that if a pro had a better way I would have read about it over the last four weeks. Have not. I have a spare F/W and will continue to try to remove my stuck one Up to, and including, cutting it off carefully. Thanks for all the advice.

 

[daselbee]

Did you try my way?

Get a heat gun, set it up pointed at the rigged and tensioned puller/crankshaft nose, turn it on, and walk away.

Come back an hour later. The flywheel will be too hot to touch. Tension the puller some more, whack with hammer.

I have had them pop off while I was gone.....

The heat gun "soaks" the heat into the assembly, while a torch puts it on localized....

I have had good luck with the heat gun, as have others here on this site after taking my advice.

 

[dkonrai]

i had the same problem with a 1954 johnson 25 hp. flywheel had never been removed. i used a heat gun, then a good rap with the 5 pound sledge on the puller. o i also shot lots of penetrating oil.

 

[daselbee]

Get it off yet?

 

[buddhapi]

I definitely feel for you. I deal with lot's of 30+ years' retired engines that have laid outside forever, and always manage to get them off with my trusty steering wheel puller. if you have a can of WD40, throw that can as far as you can towards your nearest sanitation dump. get a can of PB Blaster and a small torch. heat the flywheel 2-1/2 to 3 inch diameter from the crank and keep alternating heating and spraying the penetrating fluid every 15 minutes or so. keep the center puller bolt tight. cycle this for about 4 hours and leave sit overnight after dousing with PB Blaster one last time. in the morning, you need to head out the door with intentions of getting the flywheel off no matter what the cost. take a 4 to 8 pound mallet (short wood handle) and hit that center puller bolt like you're driving a railroad spike. you HAVE to mean it! Wallah! please let us know how this turns out.

 

[waverly23]

Long story short. I ended up cutting the old F/W off. Took my time and did not damage any ignition components. What did I find you ask. Long story short, a three piece makeshift key epoxied to the crank keyway and F/W. That will be another story. No wonder nothing worked. I did manage to get the entire mess cleaned up and useful again. I did replace my broken throttle cam and replaced the F/W with one from ebay. I did get a couple of pictures by lost them in the cloud. I'll try to find them and post. Now, however, after torquing my new F/W I find that it rubs against the ignition module slightly (I did not touch the module during the cam replacement). I did however have to remove the ignition plate to get to the cam. Other than trying to find a $50 used locator ring tool is there another way to set the air gap corrected? Or, is this not a problem? Or, is my new (used) F/W deformed? You're all being very patient with a guy that seemingly continues to step in it.

 

[waverly23]

Motors back to running good again. Starts on the third pull and is smooth through all transitions. Thanks for all those who helped in this "abnormal" problem.

 

[Robert Ellis]

I've been known to use a 1/2" drive impact gun - never had one not come off - good advice about the penetrating oil and leaving the nut a bit on!

 

[Sea18Horse]

In reading through this thread it occurs to me there is a point here that needs to be addressed. When you go to rap on the puller bolt you need to be holding up on the flywheel to the top of its end-play travel. (When you lift up on the flywheel you can feel a few thousandths end play in the crankshaft). If you don't do this, in order to impart any force to the flywheel/crankshaft taper seat you must either A, actually deform the thrust bearing itself or B, move the mass of the entire engine. By lifting up on the flywheel you save the thrust bearing from any undue stress and you isolate the relatively small mass of the crankshaft from the rest of the engine. This makes the rapping that much more effective. And yes definitely leave the nut on a few turns.

Cheers.........................Todd