6V Dynamator - first hand experiences...

[Roland Alcock]

Vince Leek's document on the DA7C site is clearer as the changes are shown in colour. The Accuspark supplied Vince doc, is in b&w.

Roly

[Bob Culver]

If nothing else a graphic illustration of the remarkable properties of cast iron. From the photos the mesh angle is suspicious but with so much wear anything likely*. All we need now is for someone to announce they have used SAE30 API SA or Mobil One  or somesuch  and no wear! I have seen Sevens with an external oil feed to the gear and with double the input power may be worthwhile. Few appreciate the significance of the feed groove.
Skew gear use and the operating condition  is so unusual one would reasonably expect whoever cut the gears to question the material. I guess the UK is no longer a land of craftsmen.
 
*(In the early 1970s I purchased a new Indian lathe from catalogue. Everything was abysmal. The artisans that made it were apparently still transitioning from bow lathes. File finish of spindles and all grossly mis aligned. The helical backgears are cut to slightly different angles and engage on the very end of the teeth. Fortunately not required to do heavy work..The leadscrew was ¼ higher at one end than the other. But the key element of a lathe, the  bed, is straight, sufficiently so  with a lot of tinkering to rebore cyl liners)

[James Anderson]

This is a very important thread and raises the equally important point that we should not discourage manufacturers to produce ambitious components. However, like some others, I run several Sevens and often purchase parts while they are available and store them for future use. I haven't succumbed to this one yet and am grateful for all the 'road tests' and observations but feel that there probably should be a general alert system at the head of the Forum to draw owners' attention in a similar position to mine to this problem in the event that they've not seen this post. The editors of the various area magazines could also maybe write a similar warning to those who tend to read magazines and are not so internet savvy.

[Andrew Cooke]

I've splashed out on a Dynamator and dizzy, and would now much appreciate an idiots guide to what lubes/oils I should be applying and where, and what sort of service procedure I should follow.  With the change of design are there any differences to normal maintenance? Not that I'm sure what normal is.

When I pulled my original dizzy out the gears were totally dry, I'm sure this is wrong.

Many thanks,
Andy

[jonblob33]

    Sorry, I think I posted in the wrong thread first but here goes. Just checked the drive gear on my 12v dynamater. It’s only done about 50 or so miles but has lots of wear. I have replaced it with my original dynamo drive gear but now have a clattering from the timing gears.
Does anyone do new gears or am I better replacing cam gear at same time with a second hand pair?
Regards. Kevin.

[Colin Wilks]

Ian Bancroft had a good stock of second hand timing gears a couple of weeks ago - http://www.a7restorations.co.uk

[Bob Culver]

Before everyone starts to notice wear, the original distributor drive gears were not immune. Prior to older parts being introduced, the only stranding of my car was at about 80,000 when the distributor drive stripped. The original gears seemed not to be hardened (as adequate for the application) .
The distributor must turn freely. A light modern grease would seem ideal, perhaps with some moly provided it remains thin. Old original greases dried and lacked anti wear etc additives now included.
 
Years ago I bought a stack of (discarded) timing gears at a Swap Meet. To quickly grade sat each in a recess turned in a piece of wood and measured dia across two opposite balls sitting between teeth Was surprised at the range.

Defective aftermarket products are a curse. With other makes have encountered piston rings, valve guides which wear at phenomenal rate, pistons, valve springs which fail early etc etc. Not to mention fake ball races. Makes it especially awkward for persons charging out work done.
 
Admittedly based on only two sets but I have doubts about Regent cwp. The crown wheels seem quite soft.

[jonblob33]

Having found 50% of my cam gear missing has anyone changed the timing gears with the engine in situ?
Kevin.

[Geoff Halstead]

Few appreciate the significance of the feed groove.

Info/details please Bob.

Geoff - Nearly finished installing compressed air piping

[Bob Culver]

The main oil supply seems to be from the generous groove in the bronze bearing, into the bore chamfer at front, and out via the two grooves on thrust face of timing gear. Important that none of these blocked off. The inspection panel always seemed a bit of a luxury but maybe not.