11Hp Flywheel Key Sheared

Skidman

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Hello all -

I have a small(?) problem - the flywheel key on my 11Hp engine is sheared and jerks the cord out of my hand when trying to start. Um, that hurts!
Engine specs: 11HP Model# 28D702 Type 1142-E1 Code 030922ZD (Mfg'd 09/22/2003) B&S Manual Ref#: 280000

Background info: This motor is on a Husky 35 Ton log splitter, bought 4 yrs ago used. Almost didn't buy it because the motor ran like total crap and had one Heck of a metallic clang while running. Just before I walked away, I pulled the air filter cover and found the Dang nastiest air filter I've ever seen. Removed the filter and it ran just fine! Unreal. Made me wonder about the condition of the flywheel key (and the mental condition of the owner).

Used it last Nov, ran more or less ok but had a miss at full throttle. Tried to used it early Jan, wouldn't start. Put a neon spark tool inline with the plug, no spark. Pulled it a few more times and finally got a very weak barely reddish spark. Ok, rust on the flywheel, etc.

Sanded the flywheel and coil faces and reassemble; got a beautiful white/blue spark - jump close to 3/4" or more. Tried to start it, one pull - nada. 2nd pull it jerked the cord out of my hand halfway thru the pull. 3rd pull - same thing. Cold motor, pre-ignition - likely sheared key.

Stripped it down and was using my Harbor Freight Puller/Bearing Separator Set (P/N 93980) and two 5/16 X 4" SAE bolts to try to remove the flywheel. Note: had to grind some of the outer edges off a 3/8" nut to drop down into the crankshaft well as an intermediate spacer since the bottom end of the HF forcing bolt was too narrow to properly engage the chamfered surface in the well. Looked like it would work ok.

Problem: After tightening the forcing bolt a bit, it got so tight I couldn't hold the flywheel still to get any more turning action on the bolt. Used a small crowbar between one of the 5/16" bolts and the shaft of the turning bolt to restrain it. Worked for a short time but then the force bent the 5/16" bolt and cocked the turning bolt to one side. Then it bent the other 5/6" bolt getting it loose. Time for Plan B.

Questions:
1. I am assuming that the sheared key could be creating excess force between the crankshaft slot area and the inner surface of the flywheel. Would it make sense to try to knock the flywheel backwards in order to attempt to re-align the key somewhat?

I would use a piece of hard plastic held next to the flywheel surface in order to avoid dinging the flywheel.


2. I used an air gun to remove the top bolt holding the flywheel cup in place. Worked very well with a helper holding the flywheel with just a pair of gloves. Several short pops and it was loose.

So, given the difficulty of holding the flywheel still, would it be ok to use the air gun on the forcing bolt - doing short pops and starting with a lower torque setting and working up as needed?


3. Should I use 5/16" Grade 8 bolts instead of Grade 5? Last thing I need would be for a bolt to break off near the hole.


4. Also, I could pre-soak the area with a bit of PB or WD-40 in small amounts. Any concerns here?

Please advise on any suggestions.

Thx

Fred
 

bertsmobile1

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A flywheel puller is not a "puller" it is a preloader.
You do them up nice & tight then smack the centre bolt really hard and the shock jolts the taper apart.

Having a sheared key wipped around the inside of the taper can make them very hard to break free.

As you have a rattle gun, try using it to do up the nut on the puller, the jerky nature of them oft will break the taper seal.
Set it to its highest setting & if the flywheel does not break free as it tightens then stop.
If you have an assistant, get them to put a pair of pry bars under the flywheel and lever up hard.
Then smack the centre bolt of the "puller" with the biggest hammer you can lay your hands on.
The puller puts strain on the joint as does the pry bars, but the pry bars also pull the whole crank up off the bearing / bush so when you smack the end it does not damage the crank or the cases.

Penetrating fluid will do nothing unless there is a lot of rust around the key slot but heat will help.
Never ever hit the flywheel directly, they are a lot easier to damage than most would think and you also run the risk of loosening the magnets inside it ( if fitted ).

Rust on the magneto magnet makes no difference to the spark, unless it is so thick that it rubs on the coil shoes.
Cleaning the contact between the coil and ground does as dose resetting the gap.
 

Skidman

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Hey Bert -

Thx for the info - good words. About the idea of trying to back up the flywheel a bit, I was considering using a wooden 2x2 held up against an appropriate spot on the flywheel (opposite the magnet) to try to move a bit. Do you think that the wood would damage the flywheel?

I'm going to get some Grade 8 bolts for the task, and an assistant for the pry bars.

Fred
 

bertsmobile1

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You pry the flywheel at points at right angle to the magnet as that is a weak point.

Not sure what you are doing with the 2 x 2.
Just get some load on the flywheel, sip the pry bars underneath and give whatever is pressing on the crank a good hard whack.
 

Skidman

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Bert -

ALL IS WELL IN LOG SPLITTER COUNTRY!

Bought some 5/16" Grade 8 bolts for good measure and an aluminum flywheel key.

Step 1: Whacked the flywheel with the 2x2 several times to try to knock the flywheel backwards to try to get the sheared key somewhat back into alignment. Didn't look like that did much, but read on.

Step 2: Drag the air hose and gun out. Mount the pre-loader bolts and tool. Find some short strips of metal to support the crowbars. Set the crowbars into place and pressed down with fairly light force to make sure they were seated well.

The flywheel popped up. Never even connected the air hose to the gun. Ok, that's fine with me. Installed the new key, gapped the coil and put it back together. Pulled the cord twice and it ran just fine. Thirty minutes of prep and 10 seconds of work!

Thank you for the crowbar tip! I even picked up the tab for those bird's drinks! Ha ha.

We'll split wood tomorrow. Merry Christmas and have a Happy New Year!

Fred
 

bertsmobile1

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Good to hear,
Thank you for the courtesy or the "job done" post.
Very few do so we never know if they fixed it or put it on Craig's List.
 

Skidman

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One more post. Ran two tanks of gas thru it today. Split about 1 1/2 cords. Some of the 30-36" trunk sections were knotty as crap. Didn't split them, just sheared them into. Ram slowed down but the motor didn't. My 73-year old butt is tired (and the rest of me, too!). Whatever. We'll be back at it again tomorrow.

Thx again, Bert.

Fred
 
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