ET: Engine (Twin) Dynamo Fitting

[john998]

Hello, Fitting an Alton to the outfit and found this gap at the bottom of the tapered hole in the crank case.
It is nothing to do with the Alton it must have always been there. Also the sharp eyed will notice that I am using
an adapter sleeve as it is replacing a Chinamo. This should not make any difference as far as the extra gap goes.
Is this a common casting/ machining error? John.

 

[bmetcalf]

You have me thinking about my recent installation of a new Alton. I may not have ridden the bike between that and installing a valve spring cap breather with PCV valve. The breather flowed air well past the upper guide and I could feel strong pulses from the end of the hose when I ran the motor. When I fitted the Alton, I couldn't use my 1/4" closed cell foam donut gasket and get the sprocket centered on the chain and the end of the Alton seemed to fit well against the opening. Anyway, the motor was very oily after a short ride, so I assumed my breather setup wasn't good enough. You have me thinking that I am really losing primary oil. I'll check the level and decide if I need some sort of seal at the Alton end. The PD28 slinger may not be enough.

I'll also look in the area of your photo.

 

[john998]

Hello Bruce, Have not had any oil loss via the dynamo in 40 years, just surprised that have not noticed this gap before.
Could I ask where you have mounted the Alton regulator? Was going to mount it under the battery platform but I'm concerned that it will get heat from the engine. John.

 

[roy the mechanic]

I seem to remember a tapered adaptor which goes in the hole before the generator. Speak to the spares co. It will still need some silicone in there. The regulator will mount up on a piece of alloy fitted to the original mounting above the generator clamp. Put mine there, it looks ok.

 

[stumpy lord]

I seem to remember a tapered adaptor which goes in the hole before the generator. Speak to the spares co. It will still need some silicone in there. The regulator will mount up on a piece of alloy fitted to the original mounting above the generator clamp. Put mine there, it looks ok.

john,
the part number is PD32 a series D part used when fitting a E3L dynamo. if you are interested I have one that I will nether use
norman lord

 

[john998]

Hello Roy, thanks for that, I didn't know about the adaptor. This engine has two front heads so no room to fit the regulator on the clamp. Norman thanks for the kind offer , tomorrow I will remove the Alton and see if the adapter will work. How is it fitted? John,

 

[timetraveller]

When trying to make the Walkernator able to fit to as many engines as possible I found that there are at least three forms of these hole. Some are tapered as cast in. Others are machined in and others are flat, i.e. no conical hole at all. It is a nightmare and my solution was to provide a choice of three options. One for those who were using engine oil in the chain case was to provide a very soft 'o' ring with about an eight mm section. This was provided over length so that the owner could cut it to length, superglue the ends together and make an 'o' ring seal which would sit down in the hole at whatever depth was required to ensure some compression of the seal. The second solution was to provide a length of silicon rubber tube which, like the 'o' ring material could be cut to length and then glued with silicon mastic. Those were for use by those who use ATV in their primary drives. The third solution was for those engines where there is no conical hole but only a flat face on the back of the dynamo drive housing. In this case the use of silicon gasket material was suggested so that the plane face of the rear of the dynamo drive housing and the plane face of the dynamo replacement could be sealed against each other once it had been ascertained what depth of insertion was required to line up the drive sprocket with the central run of the chain.

 

[john998]

Hello , these cases have I think a cast taper which appears to be in the wrong place. They are 'D' cases and I built the engine with two front heads, this makes the dynamo drive a little congested above. Best bet is to remove the sidecar so I am not working upside-downon the primary drive. My main concern is that I failed to notice this using a Miller dynamo and a Chinamo, however it has not leaked oil in the past so not sure why I'm worried. Timetraveller, thanks for your detailed response. John

 

[bmetcalf]

Hello Roy, thanks for that, I didn't know about the adaptor. This engine has two front heads so no room to fit the regulator on the clamp. Norman thanks for the kind offer , tomorrow I will remove the Alton and see if the adapter will work. How is it fitted? John,

See Fig 11 in KTB.

 

[john998]

Thanks for that, should have thought about Eddie Stevens.
John.