wipac flywheel removal with oversize woodruf key

[doctorbob]

Hi has anyone found a engine that the previous owner had inserted a larger than required woodruf key ,and now the time has come to remove the ,flywheel (wipac flywheel)
I have tried heat ,penetrating oil ,a good heavy blow to the crank ,nothing will budge
A cobolt drill bit extra long ,failed to make any impact on the woodruf key
Any one else had similar problem ,where the incorrect oversize woodruf key has been used and ,now when you need to remove the flywheel you encounter this situation

[headdownarseup]

All depends on which dimension the woodruff key is oversized?
Not quite so much of a problem if the key is longer than normal, but fatter/thicker/wider then you've got problems!
If the flywheel hasn't been off in many a year, the chances are it's probably stuck from corrosion.

The best suggestion at the moment i would think would be a larger hammer and a second person to help you.Heat first then hit.(keeping stray fingers out of the way of course ) but try and keep the heat down to a minimum as the electrics under the flywheel dont like it much!
Follow the recommended procedure as per BS manuals. (that second pair of hands can sometimes be a big help)

A little trick i use sometimes is to use a ball bearing on the top of the crankshaft (there's normally a dimple that will accept this on the end) then tighten the nut down onto the ball bearing, then hit with a suitable hammer (carefully) while lifting upwards on the flywheel (that second pair of hands)

I've never had one yet that i couldn't remove. But there's always a first time....

Keep us posted

Jon

[doctorbob]

Hello many thanks ,I have tried all the items you mentioned ,with the exception of the ball bearing,I will bear this in mind ,

[Kevin O Connor]

I remember reading on here about some who used a piece of a ratchet belt under the flywheel to support it while hitting it with a hammer. Maybe some one else could elaborate on the way it was done.

[Oyster 49]

You can apply a limited amount of heat by using a hot air wallpaper stripper. I always loosen the nut to give around 2mm clearance and then lift the engine by the flywheel wrapping my left arm around the flywheel so you are holding the engine by the flywheel. A sharp wack with a lump hammer should do the job. Don't faff about with a small hammer though!

If the flywheel won't come off you might have to strip the engine and split the case halves to have a closer look! I had to cut the flywheel off only once, plenty of flywheels about.

[headdownarseup]

A ratchet strap (cargo strap) is another way of providing upwards pressure on the flywheel whilst being suspended from for example a roof rafter.
Same principle as somebody giving you a hand. I think just about all the BS manuals will tell you the same procedure.

They can be a bugger at times as they're a close fitting taper joint that often gets corroded.
As oyster has just mentioned, dont mess about with small hammers, it will only mess things up more. A good strong THWACK with a lump hammer whilst lifting up on the flywheel (second pair of hands) will normally do the trick. You can always replace the flywheel nut afterwards as it will get mashed up.

Stick with it, it'll come off. Soak it over night in some penetrating oil, that might help too.

Jon

[Adrian Dale]

Just make sure the person doing the holding is well briefed!!!! My wonderful partner who had neve been exposed to the vagaries of Seagull maintenance let out a scream at the point of impact and dropped the lot!!!!

AJ

[headdownarseup]

Just had an idea with this.
Doesn't John sell custom made flywheel nuts with a hole bored through them to allow for hanging the motor?
This would give you the same principle as a second person lifting up the flywheel.
Easier then to hit the thing with a lump hammer single handed provided the motor is adequately suspended a few inches above the ground.
Do you get me?

Jon

[Charles uk]

I don't think suspending the crankshaft & not the flywheel & then trying to hammer the crank out of the flywheel would be in anyway a viable method of flywheel removal, it might be best not to try this!

Perhaps I should explain why Seagull's recommended flywheel removal method works so well, but first some history.

Seagull's first flywheel, the coolie hat one that was used from late 1931 to circa 1946 was cast using a malleable aluminium alloy not really suitable for Seagull's hold & hammer method, this might be why is has an internal thread provision so an extraction tool can be used. I've seen several that have been badly distorted by the "hold & hammer".

The Villiers mk 1 flywheel was cast from a harder aluminium alloy (believed to contain zinc) so wasn't prone to distortion & hammers off very well.

All the Wipac flywheels contain a high percentage of zinc, so are harder but more brittle & can be wrecked by not having a friend to hold, (Above is a motor I picked up before xmas for John which illustrates this perfectly ).

The Seagull removal method, having a friend support the motor by the flywheel, means that the initial impact from the hammer on the end of the crankshaft tends to drive the crank from the flywheel taper, failing that, the friends arms then give, allowing the motor to move & not forcing the flywheel to absorb the full force of the hammer blow.

[headdownarseup]

Well, that's told me hasn't it!

Did i see or hear somewhere (probably quite a long time ago now) that someone had made a framework to hold the entire motor while being partly suspended by the flywheel. Something that was capable of holding the motor a couple of inches clear of the ground just for this very purpose?
Might be worth trying to resurrect this from the forum archives if it still exists!

Tis a very common problem after all and gets many questions on the "how to" section.


Jon

[Charles uk]

Jon your method wasn't suspending by the flywheel but by the crankshaft thread.

[Oyster 49]

How do you give the central nut a wack if the engine is hanging from the same nut?

[headdownarseup]

I'll have a look and see if i can dig it out from the archives but it was perhaps nearly 2 years ago. I'm half expecting the pictures have disappeared by now, but you never know.
At the time i thought WOW that's a neat little device that anybody could knock up easily in a weekend

From memory it involved suspending the flywheel so the entire weight of the motor was taken through the flywheel (same as per the BS removal method) but made into a framework that sort of clamped the flywheel at the same time leaving the skeg of the motor sitting an inch or two above the ground.(not far to fall if things go wrong)
Basically a 1 man operation leaving 2 hands free for hitting and steadying.


Jon

[tambikerboy]

Yes Jon remember it well it was an orange rachet strap I've been looking through past topics most of today no joy can't find it keep looking. ... someone must remember putting it up....reckon 18 month back so could be lost....

[conlaoch]

Hi all this may be it but pics are gone
viewtopic.php?f=2&t=5011&p=41334&hilit= ... val#p41334