1930 LF
- JohnLay
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Re: 1930 LF
Work has stalled for now due to waiting on items that are due to be delivered at the Shepton Auto Jumble. Chains for the magneto 1/2 x 1/8 and dynamo 3/8 x 5/32. also due, the magneto itself.
Spent a little time cleaning up the timing chest face and it's cover, also cut-out an new gasket, just need to punch the holes for the fixing screws- JohnLay
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Re: 1930 LF
A visit to an auto-jumble over the weekend produced some new dynamo and magneto chains, also the magneto itself that had been away for attention. The magneto was fitted all be it loosely at this stage, just to keep it getting lost or having things fall on it.
The original dynamo chain, (⅜ x ⁵⁄₃₂) was fitted with a half/cranked link which I am told are not easy to find and are expensive if you do, likewise the split links as well. There are quite a few such chains available on the internet but they are for the most part listed for particular machines and 94 year old Ariels don't figure! So I just bought a length a link longer and riveted it together myself. Fitting an endless chain meant first removing the front drive chain in order to get it over the engine sprocket, Also there needs to be enough adjustment to get the new chain over the dynamo sprocket, happily there was (adjustment is effected by rotating the dynamo) enough not only to get the chain on , but also to take up the slack.
Last edited by JohnLay on Tue Apr 30, 2024 2:34 pm, edited 1 time in total.
- JohnLay
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Re: 1930 LF
The magneto returned from "being look at" and refitted on it's platform complete with it's drive chain.
Adjustment of the chain tension a little on the crude side maybe.
Simple but effective.- JohnLay
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Re: 1930 LF
With the magneto back in place it then needed to be timed. Using an old mechanics trick of placing a cigarette paper between the points, rotating the points in it’s normal direction of travel keeping a little bit of tension on the paper. At the very moment the points begin to open the paper will release. Timing for this engine being t.d.c at full retard. This is in fact a useful “rule of thumb” for older engines where you don’t know the exact timing and you won’t be far out.
Timing using the “fag paper” method .- JohnLay
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Re: 1930 LF
The next task, remove the fuel taps from the jar of acetone where they have been soaking for the last month or so and refit back in the tank. getting close to seeing if it will actually start.
- JohnLay
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Re: 1930 LF
The little Ariel started and ran today. not for long as it's not fully back together yet.
But enough to be encouraged.
But enough to be encouraged.
Re: 1930 LF
Congratulations!
1937 Guzzi GTV, 1939 VH bitsa, 1947 VH, 1981 Guzzi Monza, 1983 Guzzi Lemans
- JohnLay
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Re: 1930 LF
Some odd jobs today, first refit the timing chest cover. However the mating faces of both needed quite a bit of cleaning of the old jointing compound a fair bit of which had ended up inside the chest.
Secondly, do something about the lubrication of the rocker shafts. Unlike more modern engines which have an oil feed to them, these need to be lubricated separately using a grease gun. To this end the nuts securing the shaft ends were formed into a conical end with a hole in the centre. This arrangement does of course not suit modern grease guns. The above photo shows the original (left) and modified form(right).
Drilling and tapping to accept modern nipples was simple enough, not as original I know but more practical.- JohnLay
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Re: 1930 LF
Attention to the clutch, you may remember when first took the clutch assembly apart there were three long an one short springs fitted. The word here (thank you Will) was that the shorter one was most likely to have been the correct one. Finding suitable replacements however took a while.
I tired experimenting with a number of odd springs picked up at auto-jumbles before settling on BSA Bantam springs. I had wondered as Bantam clutches have six springs whether four as used in a Berman clutch would be up to the task. Needn't have worried, the vice test showed that the bantam springs were "stronger" than either of the originals, The adjusting nuts (shown above the centre spring) needed a few thou shave off as the ID of the bantam springs was slightly smaller that the originals. The real test of course will come once the bike is out on the road, however it's possible to stand on the kick-starter against the engine compression without any clutch slip.
Two springs being pressed together in a vice, not the most scientific of test , but does serve to indicate the difference spring rate between the two. The lower in the photo is the original short spring and the upper the replacement.
Original long lower, proposed replacement centre and original short upper.I tired experimenting with a number of odd springs picked up at auto-jumbles before settling on BSA Bantam springs. I had wondered as Bantam clutches have six springs whether four as used in a Berman clutch would be up to the task. Needn't have worried, the vice test showed that the bantam springs were "stronger" than either of the originals, The adjusting nuts (shown above the centre spring) needed a few thou shave off as the ID of the bantam springs was slightly smaller that the originals. The real test of course will come once the bike is out on the road, however it's possible to stand on the kick-starter against the engine compression without any clutch slip.
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