OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions on Other Engines TROJAN MAJOR - Motor Fitted To Ogden Rotamatic

Still alive !

Awesome work in getting the old girl up and running paul_c!, Thanks for sharing the journey ...

I gave the cowl a test fit today, also wanted to see how it effected the cooling as I wanted to give the engine a long run
I gave it a good run with the shroud on with no problems but the fan doesn't give much of an airflow over the cooling fins.

Hi Paul,

It's starting to look like a Rotamatic engine.
The fuel tank is probably the same as that on the Motamatic(?)

Thanks for the update.
------------------------------
JACK

Cleaned up the cowl this afternoon

It's in undercoat at the moment and it will get a coat of yellow tomorrow.

Nice weather today so gave the cowl a few coats of paint

I wish I had the fuel tank but in its absence a Victa 18 tank will do the job, more painting ! I like the painting but the prep can be painful.

All fitted up

Yes, all fitted up and no place to go ... at the moment.
It is unfortunate that this engine was separated from its chassis long ago.

All I can say is that we are lucky one of these Ogden Tor Majors survives.
I just hope, one day, one of the bases will turn up.

Paul, I'm glad you saw the historical significance of this little moter
in the context of AUS vintage mower history.

This has been a great post and story. One for the record.

p.s. I love the old lanyard handle.
----------------------------------------
JACK

Thanks Jack,
I have asked Grant aka Silensmessor to work on a decal for me, hopefully will have it soon along with a few others. Once it's all finished I will take a final photo and video for the record.

Won a fuel tank off EBay that looks and measures the right size




Hopefully the tank will be with me soon and the decal is being worked on :-)

The postie came through with the goods,

I will repaint it very soon :-)

An update on this one, I have been unable to find a mower base to put this engine on but have been successful in purchasing a complete mower

Hopefully after some work I will have it running again :-)

Thats awesome too see Paul!

I was going to have a crack at this one but you beat me too it.
If I had just gotten that base at the swap meet you could have had 2!

G'day Paul & Kye

Congratulations Paul.
I feel these are one of the top 'desirables' of the 1950s era.
They would have looked stunning in their green and yellow livery.

I note this one has no branding cast in the base or wheels.
Paul has told me it still has two original design fixed blades, and
has retained its spring shock clutch! They have never been recorded.

I note that my brochure shows a similar machine:

I did some work on the mower yesterday, required a set of rings and a carby clean. Wanted to remove the engine but ran into some problems with the blade plate. Mine doesn't have a hex nut like the model shown in the brochure but a bolt that has two flats, this would not budge.

Clutch is still there with the spring above it.
I am sure I have seen a photo of another blade plate that has the clutch on the other side, leading me to think that there is another model of this mower out there ?

Found it.

I can only say this is new territory, and put in my two cents' worth...

The photo you show is an amalgam of an ad and a separate maintenance
manual. The brochure suggests an above-holder spring clutch. The
maintenance manual photo suggests a below-holder clutch. A non-hex nut
is new to me. Is that a brass nut?

It may be that Ogden did change the blade holder design, taking into
account another source: the Ogden Story book (that you also have).
All sources suggest to me a conventional RH hex bolt.

In any case, the issue is, I guess, left or right hand threads?
My understanding of the clutch design is that this bolt does not,
and could not, connect directly to the crankshaft. The bolt screws
into the female-side of the clutch. The male side of the clutch is
secured by another bolt (or boss) to the crankshaft. The maintenance manual
does not hint at a LH thread.

Did other makers use this clutch system?
The answer is 'yes' - but with a twist (pardon pun).
I know that both Whirlwind (Sabre) and Pye-Tecnico (Automotion)
used a similar arrangement, but with a rigid bar blade, rather
than your rigid blade-on-disc system. Here is the Tecnico system,
with the spring clutch below the blade:-



I guess this doesn't really help, Paul.
I have written before about the lack of documentation of these safety clutches.
I believe they were replaced - in service - with a simpler and more elegant
solution - the swing-back blade. After all, these clutches suffered constant wear.

But this conversation is part of the record of this most fascinating and
important Australian lawnmower - the Ogden Rotamatic.

--------------------
Jack

Hi Jack,

Yes I agree, looking at the picture I would say the blade plates are different with the clutch remaining in the same position. Either way I will have to remove it to paint the base, it does look brass in the photo. I will have to have a closer look :-)

Sorted out a few carby issues and I am now happy with how the mower starts and runs, I am not a big fan of these Dellorto carbs with variable mixture.

[video][/video]

That runs awesome Paul! Great to see you do your magic on another one. Just wish I got that base at Gympie for you, you could have had 2!
Oh well, next time.

Cheers Paul!

Hi Paul & Kye,

I guess that's the first video of an Ogden Rotamatic!
Just a couple of years ago, no one had heard of these mowers.
Now we have a complete running one. The mower seems to attract
women in beach attire ...

Paul, can you explain this to me ...
its the 'baffled ejector opening'.
Is it 'impossible' to injure your foot?