Getting her running

Janet · Post by **Janet** » Sun Nov 13, 2011 11:02 pm

Take the points back plate off and, with the piston set, position the advance/retard unit correctly. It took me about 9 months to get it as right as I'm going to, but the effort was worth it. Then replace the backplate so the slots sit mid way on the screws. It can be fine tuned from there if needed.

Make sure you time it with the piston on the correct stroke.

Niceride · Post by **Niceride** » Mon Nov 14, 2011 6:20 am

Where is the correct position?

michael_s · Post by **michael_s** » Mon Nov 14, 2011 8:36 am

I am sure you already downloaded the Workshop Manual?
See illustration on page 41:

Niceride · Post by **Niceride** » Mon Nov 14, 2011 10:11 am

I have an onld workshop manual, where can I download one?

Is that with the piston at TDC?

I think my cam may be worn... Is this a common fault?

SideValve · Post by **SideValve** » Mon Nov 14, 2011 10:46 am

Undo the nut on the end on the spindle and you should see that the spindle itself is threaded. There is a proper puller but I usually just screw in a suitable bolt and with a bit of a tug it comes free. Don't force it. Then I set the plate in the middle of its adjustment range, turn the crank to get the piston in the right place, hold the weights open and adjust the cam position so the points are about to open. Do it up carefully, then turn the engine and fine adjust in the usual way.
While you've got it apart make sure nothing is too worn and that its all lubricated & moving nicely. Check the backplate is secure on the spindle.
Sort of tedious but satisfying when its right and running.

Niceride · Post by **Niceride** » Mon Nov 14, 2011 10:51 am

Thanks Peter! Will let you know how I get on.

BigAl350 · Post by **BigAl350** » Mon Nov 14, 2011 11:35 am

Trouble is, the auto advance and retard units on Lightweights can't be lubricated or repaired at all easily, so many are knackered, and there have been reports of them disintegrating on the forum!

It's best to do the ignition timing on the bike with the unit in full advance position, I find they all run fine like this.

A far better alternative to the knackered advance unit would be to fit an electronic ignition set-up (converting to 12 Volts at the same time and enjoying good lights!).

BigAl (Whose 1960 AJS Model 8 350 passed the MoT on Saturday with no advisories so feeling very smug - until the next thing breaks!)

BigAl350 · Post by **BigAl350** » Mon Nov 14, 2011 12:08 pm

https://www.jampot.com/article_read.asp?id=395

Essential reading on the Lightweights, as is

https://www.jampot.com/article_read.asp?id=507

BigAl

Niceride · Post by **Niceride** » Mon Nov 14, 2011 7:10 pm

She runs! Fiddled with the cam position and changed the plug and had her running in no time.

She it still quite loud, maybe too loud(is there such a thing)? I have fitted the new silencer but am wondering if there is something else wrong? Also I think my tappets might be hitting the cover plate. Is this normal, if not how do I stop it happening?

Speedo isn't working so I'm going to order a new cable and worm drive (i'm guessing like my other old bikes this is all that needs replacing to get it working)

Carb needs a fiddle I think - Even when hot I need the choke on to open it up without cutting out when I'm riding. I think maybe an adjustment to the fuel needle/jet might sort it out. It will also run quite fast when it first starts. I wonder if the timing is still slightly out but at least its running.

RAY BOWMAN · Post by **RAY BOWMAN** » Mon Nov 14, 2011 7:32 pm

Hi Robin,
My silencer was very loud at first but, I
introduced some steel wool into it. A big
improvement, but you need to experiment.
An afterthought! do you have a pepperpot
fitted to the exhaust pipe?.
Ray.