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Fly Wheel Replacement
jobie - September 14th, 2015 at 02:40 PM

Hi All,

I need to replace the fly wheel in my 56 beetle. I have pulled the engine out and the teeth are stuffed (in two places). The gear box has been ground away also.
Can I assume that I have an early Gear box and someone has put a later flywheel (1500 engine) onto it and the teeth have worn away the gear box?
If I fit a new Flywheel what are the chances of it wearing like this one? do i need to make any mods to avoid this?

Cheers,

Joel


adlbeetle66 - September 14th, 2015 at 03:39 PM

If the teeth are still just touching, grab a 60 grit emery flapper wheel that goes on the drill and clean it back a little more.. Then the new flywheel will fit better :)


bevoracing - September 14th, 2015 at 05:21 PM

You have a 200mm (later) flywheel, probably 12 volt.
The wear is all normal. The worn spots are because the engine stops in those 2 places every time.
If you need to get going quick you can remove the flywheel and shift it 1 dowel pin, ¼ turn.
If you do that carefully file off all the burrs, that’s what’s touching the gearbox case, hardly a mark really, no issue.
6V flywheels are 272.5mm OD and have 109 teeth
12V flywheels are 276mm OD and have 130 teeth
You must use the matching starter motor, and the starter bushes are different, but there are adaptor bushes both ways. A 6v gearbox, large OD starter bush, will need clearancing slightly for a 12v flywheel, no biggie. Replace the starter bush while you're in there.
200mm 6V flywheels (rarer now days) come with or without an “O” ring in the centre, think they’re interchangeable.
Replace the seal with the most expensive one you can buy, all the rest are crap. If you use a second hand flywheel put a “seal saver” or “ezy sleeve” (I think that’s what they’re called) on it to fix the seal groove, then it really won’t leak. You get them from industrial bearing & seal suppliers, CBC etc.
Have Fun
Tony


jobie - September 15th, 2015 at 01:36 PM

Thanks heaps guys. I will count the teeth and go from there.

Anyone have any advice on how to get the gland nut off?


grumble - September 15th, 2015 at 04:43 PM

If you have one of the original spark plug sockets,fit it between the flywheel teeth across to the exhaust pipe outlet from No 1 cylinder,this will effectively lock the flywheel,then with a 36mm socket and a 3/4 drive bar with a length of pipe on it to extend the length simply undo the bolt. you may need some one to stand on the opposite side of the motor to stabilise it .


jobie - September 15th, 2015 at 10:25 PM

Now I'm getting somewhere.
The fly wheel did have 109 teeth so I guess it's a rare 6 volt 200mm flywheel that will need replacing.
Maybe someone in Melbourne might have one they can move on to a loving new home......
Do I need to check the starter and starter bush (not sure what this is) or will the one that's on it be the only one that will have worked in the first place? i.e. the 130 teeth I have to build a new motor will not be able to be used on this one?

Cheers,

Joel


bevoracing - September 16th, 2015 at 02:39 PM

Joel
You have a couple of options.
1 – Find another 6V 200mm flywheel, you can’t buy them any more I don’t think. (May be able to get a new ring gear put on yours, don’t know?)
2 - Get a 12v flywheel, a 12v starter motor, and a 12v to 6v adaptor bush, 12v starters have a smaller shaft. (This is the little bush in the gearbox casing that the starter motor shaft goes into, you always change this bush while the motor is out, they wear out regularly)
You will also have to clearance the case a little to clear the larger flywheel. This is common, just take out only what’s needed with a rotary burr, it doesn’t do any harm.
You can buy new 12v flywheels, in the US, so in Australia too :-
http://www2.cip1.com/ProductDetails.asp?ProductCode=ACC-C10-5096 
Here are the available bushes :-
http://www2.cip1.com/SearchResults.asp?search=Starter+Bush&Submit= 
Here is the flywheel seals :-
http://www2.cip1.com/SearchResults.asp?search=flywheel+seal&Submit= 
I would use the German double lip silicone seal.
Be sure to tighten the gland nut properly, and use a torque wrench to set the clutch cover to flywheel bolt tensions correctly. Over tightening them causes clutch shudder (strange but true).
The starter you have will be 6v, they aren’t interchangeable.
Put a jack under your gearbox and take the weight to check the rear engine mounts while you're in there.
Good luck
Tony


jobie - September 30th, 2015 at 07:27 PM

Can someone tell me what gear box I have. I have found the serial number and it dosen't have any numbers preceding it