OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Victa Walk-Behind Rotary Mowers Rotomo Flywheel Grinding

G'day,
I'm trying to get an old Rotomo running, but for some reason I can't determine, the flywheel keeps grinding on the stator plate when it spins - just in one spot forward of the coil, but not enough to stop it spinning. Any idea what could cause this? It started fine with no grinding, then I stopped it to adjust the points and removed the flywheel, but since putting the flywheel back on it has started grinding and I can't get it started again. Any help would be appreciated!

Hello bestseller

I notice that this is your first post. A warm welcome to these forums.
The issue you have is unusual, and we will need more information.

'Rotomo' covers a number of models - (even the first 'fan mowers' were
named Rotomo).

I'm not the expert on these, but I can assist with what you need to do.
For example, we would have to make sure of the basics - the correct
flywheel for the stator, the flywheel or stator plate are not damaged.

A photo of the stator with flywheel removed.
A photo of the flywheel.
A photo should include the grind marks.

For information to upload photos, click HERE.

Hope this helps.
--------------------------
Jack

Thanks Jack,

It's a model 2 Rotomo, late '56, 125cc. I won't be able to upload images for a bit, but any advice otherwise would be a great help.

The flywheel only grinds once in a 360 degree rotation, right on the raised area of the stator plate forward of the coil. It's strange because it wasn't doing it until I removed the flywheel to adjust the points. I cant see any damage, but I'm concerned I may have knocked the crank out of alignment possibly?

Hello bestseller

Okay, the three causes could be:
- bent crankshaft
- out of true flywheel
- bent alloy stator plate

That the flywheel only grinds once in 360 degrees suggests
to me either the c/shaft or the flywheel. Most likely cause,
an out-of-true flywheel (rather than c/shaft).

Any help or input from members most welcome.

Hope this helps.
---------------------
Jack

Hello Bestseller,

Just wondering if you used a flywheel puller or a hammer and screw drivers to remove the flywheel ? A hammer could have bent the end of the crank enough to cause this problem, you could try moving the pulley around until it sticks and then tap it with a piece of wood and a hammer back the opposite way. See if this resolves the problem.

Pictures will help a lot, I would pull the flywheel again before anything else to see that nothing has become dislodged or is loose. Doesn't take much in the way of dirt etc to cause a grinding issue.

Thanks Paul and Jack,

I checked the crank alignment and it appears good, so I tracked it down to what I think is a slightly cocked starter plate. A gentle hit with some light steel wool on the offending surfaces and its barley contacting now. She started up no problem.

The next issue I have is a slack small end bush. Anyone know the measurements/size of the sint bush I need or place to get one?

The little end bush is available but requires reaming for a correct fit. I bought my reamer from the UK. If you search the online parts store above and to the left you should find the bush in stock.

Piston pin is NA, perhaps enquire about this

https://www.outdoorking-forum.com.au/index.p...amp;inc_subcat=0&sort=20a&page=1

Bush

https://www.outdoorking-forum.com.au/index.p...amp;inc_subcat=0&sort=20a&page=2

If I can find the reamer on EBay I will post it here, you need to ream the bush to suit the pin after the new bush is fitted to the conrod

Here is the reamer, you will have to check the sizing to be sure it's the right one for the bush.

http://www.ebay.com.au/itm/Engineers-Adjustable-Hand-Reamer-Tools-5-16-11-32-7-9mm-to-8-7mm-HZ-Size-HSS-/400559618868?hash=item5d4336bb34:g:F5oAAOxyHWJSGNVP

Hope all this helps

Bloody hell, thanks Paul! You've gone above and beyond - thanks mate.I'll give BSC a shot, but I doubt my chances there. Your suggestion will be a goer I'd say.

Whilst on the topic of BSC, I managed to pick up some accurate sint wheel bushes to suit tin wheeled Rotomos from there a couple of months back. Not cheap at $8.00 a pop ($16 per wheel), but they fit perfectly and match the originals precisely (1/2 X 5/8 X 3/8). You'd probably need to order ahead as they aren't stocked very often. Part number is C1620-5.

check the key to keyway fit on the flywheel???

G'day Jonesy,

Yep I checked the keyway fit and it looks good - flush all round. Still pretty sure its a cocked stator plate. Should there be washers between the plate and the crankcase?

Also, could anyone with a bit of Christmas spirit help me out with a copy of the Model 1/2 magneto/stator plate assembly?

There's one on EBay here

http://www.ebay.com.au/itm/VINTAGE-VICTA-WICO-MAGNETO-ASSEMBLY-HOT-SUIT-18-or-ROTO-MOWER-WAS-SPARKING-/291642379512?hash=item43e73d8cf8:g:h8QAAOSw~otWdR2n

Sorry Paul, I wasn't very clear - I meant a copy (pdf) of the model 1/2 magneto assembly instructions from the green book. Thanks though!

Jack, you're a star! Thanks and merry xmas mate!