RAD flywheel trashed?

Pablo

sqeez bth levrs & lean bk
Site Supporter
Location
georgia
here's a couple of pics of my RAD total loss flywheel after having timing issues this past week. Paul Lehr suggested I look at my flywheel as a source of timing changes that occured spontaneously after my ski stopped suddenly after a few nose stabs. I pulled the flywheel and found that the woodruff key has dug into the flywheel. As a result of what??? I've done a thousand nose stabs/attempts and never noticed anything like this occuring. My timing was off about 4-5 degrees when I checked it yesterday and I pulled the added timing off with the brain and it ran fine until I tried another nose stab yesterday and the same results happened. I assumed the pickup plate had moved, but those bolts were snug as was the flywheel when I pulled it. Look at my drive shaft as well. The woodruff key is stuck in the recess and has actually dug itself into the shaft too!! U guys have any thoughts? I'm assuming the flywheel is trash. What do you guyhs think. There's some play in the flywheel when I rebolt it. How do I get that dang woodruff key out?
 

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Waternut

Customizing addict
Location
Macon, GA
The woodruff key just sits in there. Typically you just push on the front or back edge and it pops up enough to grab it...or it falls out on its own. If it's being stubborned, give it a light tap with a rubber mallet or screwdriver.

I can't remember if you have a torque wrench or not but how much do you tighten the flywheel? It's supposed to get a lot by comparison. Off memory, I want to say it's around 50-55 ft-lbs and your spark plugs are supposed to be 14 ft-lbs for comparison.


btw - Is that just residue on the pickup or was the flywheel hitting it and grinding it down?
 
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Pablo

sqeez bth levrs & lean bk
Site Supporter
Location
georgia
The pickup had silicone residue on it. I couldn't get my play-dough to stick to the pickup when I was measuring the gap so I mixed the play-dough with silicone for it to stick and that's what's left over. I did torque the flywheel down per spec on the initial install this spring. It's never slipped or had a prob til this last week when I ran it. I farkn' hate wrenchin'!!!!!!!!!!!!!!!!!!!!!!!!

The woodruff key just sits in there. Typically you just push on the front or back edge and it pops up enough to grab it...or it falls out on its own. If it's being stubborned, give it a light tap with a rubber mallet or screwdriver.

I can't remember if you have a torque wrench or not but how much do you tighten the flywheel? It's supposed to get a lot by comparison. Off memory, I want to say it's around 50-55 ft-lbs and your spark plugs are supposed to be 14 ft-lbs for comparison.


btw - Is that just residue on the pickup or was the flywheel hitting it and grinding it down?
 

SUPERTUNE

Race Gas Rules
Location
Clearwater Fl.
Did you torque this to at least 65 ft-lbs?
Then re-torque at a later date?
This would be the recommended way to properly use an aluminum hub flywheel.
I can see that yours must have been loose.
 
i did the same thing with my RAD flywheel.... didnt tighten it enough i guess and it spun and the key actually landed up crackin the flywheel.... now i just impact that SOB on.
 

Waternut

Customizing addict
Location
Macon, GA
For pablo's sake... If he were to line up the flywheel properly and then torque it to 65-70 ft-lbs, do you guys think that flywheel could be used for a while longer even though the woodruff key area is messed up?
 
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Pablo

sqeez bth levrs & lean bk
Site Supporter
Location
georgia
I did not come back to "retorque" it after the initial install. I'm sure I torqued it to specs initially. This occured or was noticed after I pulled the flywheel looking for trouble due to my timing being off by atleast 5 degrees or more. Do you guys think it's trashed now? There is noticable play in the flywheel when I retorque it on.

Did you torque this to at least 65 ft-lbs?
Then re-torque at a later date?
This would be the recommended way to properly use an aluminum hub flywheel.
I can see that yours must have been loose.
 

Pablo

sqeez bth levrs & lean bk
Site Supporter
Location
georgia
No backfires that I can remember. I hit those few nose stabs and subs. It died on me and I found the flywheel damage after I started investigating. When the probs started it would barely stay fired and would run real rough, cough, choke sputter and nearly backfire, but no real, hard hitting backfire notes were heard.

Did you have any backfires? That will damage the key & flywheel for sure
 

Waternut

Customizing addict
Location
Macon, GA
I still think having a shop weld a piece back in there and then cut it back down would be fast and cheaper than trying to find even a used flywheel. The other alternative is have a shop just cut it all back to that new line. Everyone keeps saying the woodruff key is just there for alignment but when the woodruff key digs in, everyone seems to think it's junk instead of adjusting the timing and torquing it back down. There are also offset woodruff keys made specifically designed to advance the timing but I see no reason why they couldn't be used to retard the timing in the exact same way. Heck install the flywheel on the crank with red loctite. You may never get it back off but at least it won't move.

Maybe I'm wrong but just seems like a waste to trash a flywheel for something simple like that. If the flywheel was cracked, then by all means, junk that b*tch!
 
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SUPERTUNE

Race Gas Rules
Location
Clearwater Fl.
I'd try and use it again...what do you have to lose other than $600 for a new TBM charging flywheel?
Use green Loctite I believe it's a medium strength, just use it in the keyway groove.
TORQUE to 65 FT-LBS! Use with a new bolt also would be a good idea too.
 

Big Kahuna

Administrator
Location
Tuscaloosa, AL
I had one that developed a crack, really hard to see, but when you tried to bolt it down it just opened up and slit farther on the snout of the crank.

Try what Chucky said.
 
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