Ignition Timing

[Beddo88]

Hi all, been having problems with the carb since i bought the car, and i'm slowly witling them down. Sorry for the long post, just saves me giving info in bits!

For reference its an 87' Scala, with the standard Pierburg.

Initially the car was idling at between 1800-2000, but i have got this down to 1600 checking parts, then around 700-900 by playing with the idle screws. The car itself idles very unevenly, splutters and jumps between 700-900. When in low rev ranges (say between 1000-2000) it chugs and splutters alot whilst driving, which is incredibly annoying, and often causes it to stall when pulling off.

So far i've replaced the waxstat, removed and checked the autochoke then re-aligned it (it was out previously), Checked all cables going to the unit for correct voltages and checked the pull down unit. Slowly beign pushed towards a weber as it seems MUCH less effort, but being a poor student its not a cost i really want to incur.

Is there a chance that the fueling / timing is out? I havent checked the timing yet, but intend to when replacing the timing belt.

How do i go about this?

Cheers in advance, Dan

[Nate]

line up the TDC marks on the crank pulley or possibly thru the inspection hole in the flywheel housing (but if you're about to do the timing belt, do the following while you've got it at tdc anyway) pop the dizzy cap off, check that the rotor arm it in line with the little notch cut in the rim of the dizzy body. i normally then advance it until it pinks unde load, then back it off ever so slightly

[Beddo88]

When you say pinks under load, i'm assuming you mean with the engine running and adjusting the dizzy during the running? What sort of rpm would you use? (Still new to engines, one thing i havent learnt anything about!)

[Nate]

advance it a bit, drive it, repeat until it pinks, then back off the timing a bit. properly unscientific trial and error method, but it works well for me :)

[Beddo88]

Thats my kinda tinkering :D Cheers!!

[Nate]

if it's the first time you've done it, mark where the dizzy is at the moment. should you manage to completely balls it up, you can always then reset it so that it'll at least run. try to adjust it by small increments

[Beddo88]

Yea its my first time lol

Good idea!! Cheers! Havent had a chance to look at that manual yet, been overrun with work but hopefully it'll help! :)

[Brunty]

Sounds rather like the fuelling is wrong on idle. I'd get it to a garage to set up the CO on a gas analyser first of all.

(Under light throttle the carb is still only using the idle jet)

[Beddo88]

I see.... i have a mate whose got one so i'll get him to bring it down. Cheers for the heads up! :)