I have just fitted a powerspark electronic points system to my 126s 650cc engine and need to fine tune the timing (getting pinging under load). I've got a basic strobe light and have looked at my Haynes manual that states that the timing mark on the pulley should line up with the 10 degree mark when the engine is at idle, but I've also got an old Autobooks manual that says the lines should line up with the engine at 2000 rpm. Which is correct? As I've only got a basic strobe is there an easy way to figure out when the engines at 2000 rpm or is it going to be a case of best guess?
Tuning Timing question
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Tuning Timing question
the hobbler
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the hobbler
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The timing marks should line up AT IDLE. However, modern fuel is tending to upset the advice given in the (pre-ethanol) books, so you might have to play it a little 'by ear'. I always recommend that on classic cars the VERY BEST petrol that you can find is used + some 'anti-ethanol' gunge. According to their web-site, Esso "99+" is ethanol-free in most of England, even though it says E5 on the pump. Even using this fuel, I would still "belt and braces" put the recommended dose of 'gunge' in the tank
If you're using the strobe don't worry about the static or 2,000 rpm reading. You only need to check the marks align when static. Make a new mark on the pulley or timing cover that is 28 degrees BTDC. You need to calculate that by working out the circumference of the pulley divided by 360 degrees multiplied by 28. I think the answer is 36mm. So that's a white mark at 36?mm (check) to the right of the pulley TDC mark. Paint the TDC mark on the timing cover white. When the engine is on the +3,000 rpm range adjust the distributor to make the marks align.
You can't do anything at intermediate rpms as this depends on the bobweight springs being at original spec.......unlikely. If the above can't be achieved it's likely that the springs are faulty or the bobweights seized.
Thanks for the advice. The fuel is a very low at the moment and I suspect a bit old (which I suspect is a small part of the pinging problem) so I am going to fill up with Esso 99+ plus I've got some Millers VSPe to put in as well. I'll tackle the timing again and like you say play it by ear a bit and keep on tinkering!
Well after putting in some Esso 99+ I finally got round to looking at the timing today. It took a bit of fine tuning but the car seemed happiest at about 11 degrees at idle. Took it for a spin and the difference was unreal, the engine felt like it had much more torque and was a lot smoother. I would definitely recommend the powerspark points replacement.
