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Replace the dog
#1
Bit of advice please.

The Chummy engine was apparently rebuilt before I aquired the car last year. However, the starting handle would not engage firmly with the dog and when I got the handle out the end was not in a good state. I got hold of a decent handle but the engagement was/is still very poor - so I guess the dog must be damaged.

The question is - is it possible to change the dog with the engine in situ (having removed the cowl and radiator).? 

It's a 1927 mag engine.
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#2
Yes it is and will be apparent once you do remove the cowl
Black Art Enthusiast
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#3
Yes, it is possible but the hexagon on the starter dog lies behind the little alloy housing on the front of the timing case. Unless you have a very deep socket (I forget the size off-hand),  access to the hexagon is poor without stripping the front of the timing case and there should be a lock washer present. Stripping the case is quite a complex job as that front panel retains the timing gear bearings.

However, it may be worth checking the alignment of the handle shaft and the dog, through the cast iron guide. A few degrees of error isn't a problem but my Chummy took a lot of lining up and fiddling with the guide (reproduction part) to get reasonable engagement. Even now, the handle is good enough to turn the engine but I wouldn't like to try and start it that way as the engagement is still not 100%.
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#4
Thanks Ian and Parazine. How did I just know it would not be an entirely easy swap...
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#5
I refaced the dog on my early coil engine in situ with an angle grinder.
Both the dog and the handle shaft dogs need to be undercut slightly to prevent the handle being thrown out of engagement when cranking the engine.
Jim
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#6
I've done this on my chummy a few years ago, got the new dog case hardened after reshaping. Took a fair amount of work to get them to engage nicely with each other both ways round.

[Image: 8793027496_1c87e05e19_c.jpg]

[Image: 8795089625_b79e916d07_c.jpg]
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#7
hi all.

i seem to be getting alot of people ask for mag engined starter dogs at the moment.

i take it nobody are making new ones.

i done a batch of 30 many years but with heat treatment and a small batch, they had to sell for £45 each, at that time pheonix were charging the same for a pressure fed dog.

tracy asked me if it was worth making another small batch? with rising heat treatment prices etc, they would probably have to be £60.

would the austin 7 world realisticly pay this, or does everyone rely on the starter motor?

it took me 10 years to sell the last 30 ???

input welcome.

tony
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#8
Is it possible to use the later type on a mag engine? Obviously the handle would need modifying....


Attached Files
.jpg   Starter dog.jpg (Size: 33.32 KB / Downloads: 269)
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#9
Thanks for the additional replies and helpful pics. 

Not having done this particular job before on an early engine, when removing the timing gear cover is there anything likely to fall/spring out (timing gear bearings?) and thus cause me to have to take the engine out and entirely dismantle it in order to get the tiny widget back in?!
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#10
Hi All

I use a later “hook” type dog on my 29 coil engine.  I’m not sure if it will work with the Magneto engine.  The handle needs to be modified with a removable pin as that is the only way to get the handle out of the nose piece.

Cheers

Howard
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