Hi. OK, newly rebuilt engine went back into the van today, and I did the 20min break in (which was very painful!). Now I need to set the timing properly. I have my timing light, but don't know where to set it. Engine Spec is - Type 1 Engine 1641cc Scat Cam (C25) 009 Distributor What degrees from TDC should I set? Thanks
if you've not got a tacho, you'll need one. make sure valve clearances are good. warm the engine up. slacken the dizzy clamp connect the timing light as per, and run the engine up steadily, whilst watching the timing marks move (the dizzy is advancing).... at some point you'll notice the marks stop moving (total advance, 'all in')...note the rpm hold this rpm and turn the dizzy to set the timing at 30 degrees... tighten the clamp bolt. re set the idle and note the timing. with a scat cam and 009 the idle may be a bit lumpy.....don't be tempted to advance the dizzy to iron it out.....you'll overheat the engine go for a spin....if you hear pinking, back the timing off a degree or two....if the pick up is pants, notch it forward a couple....but don't go mad...it's a new engine
That's great. Thanks for that. I read online also that out can start with a 7.5degs before TDC to help with the initial start. Does that sound about right?
yep....009 have about 22 degrees of advance in them, so that equates with 27.5 total advance.... think about what you're trying to achieve....as the engine RPM increases, you want the spark to happen sooner....too soon and you're igniting the mixture before the piston is in the right position...pre ignition...pinking....
OK. Got it. I'm going to static set it to 7.5 before TDC (BTDC), Start the engine, and ensure that as it goes through the rev range ensure it does not go past 30deg. One other question. It's a newly built engine, is it OK to rev it upto 3000rpm? Sorry, another question. At low revs I did see a flame in the air filter (I have twin carbs on it). Is this also a sign of pre ignition? Only saw it once, and as the engine revs got higher, the engine ran a bit smoother.
With my New rebuild I took it to garage to set carbs and timing up on the rolling road! At that time he took it up to 3000 rpm and said it was fine to do so but no higher for 500 miles! Then change engine oil, ran in simples! Zed also made a good point and that is to not put to much load on the engine in an attempt to not over rev it as this is probably worse for a new engine
Yes, I plan to do the same. I have twin carbs, so will look to get them balanced too. But, as it is now, its way to rough, and I need to set the timing best I can before I take it out on the road. Then its tune up time!
set the timing to 7.5 so you can get it running. then balance the carbs. Once the carbs are balenced then go back and to the 30degree timing
I run dual carbs, balancing is not that hard, but you do the tool to check the suction of each before any other adjustments. Sounds like you're on the move again. Congrats!!!
Just remember that on the rolling road they not only balance your carbs they also analyse the exhaust fumes and ensure carbs are jetted correctly from tickover up to 3000 rpm Once ran in I will be taking the bus back to check jetting up to full revs!
No....if anything it's the opposite....will be fine once timed up properly and the carbs are sync'd properly....pay particular attention to the throttle opening....both carbs need to be absolutely bang on, or you'll struggle to set the air draw (balance) and everything else that follows....as it's a new build, the compression will be uneven, until the rings and bores have bedded in.....don't worry if they seem different initially
Sorry for the hi-jack, have been following with interest. Following some setting up issues, Anni has just returned from a rolling road with some significant improvements in running at all revs and loads. I have yet to check fuel economy but the engine must be running more efficiently and hopefully more economically. The garage recommended changing to electronic ignition as she's got a Bosch distributor with points, is it an easy & sensible task to just change the points within the existing distributor for the accuspark or powerspark modules mentioned in other recent threads? Just a bit wary changing things as she is now running far sweeter than ever before. BTW 2L type 4 engine with new twin Solex carbs and old vacuum Bosch 009 distributor with mechanical points and old coil.
I'd wait until it's service time again....straightforward swap....but you'd need another coil to suit
Maybe I'm a heretic, but an engine 30-40 years old may well not have the correct timing marks. It may well have been reconditioned more than once, with different crankcase/cylinders/heads and a pulley with inappropriate markings. Perhaps the best timing for such a "composite" reconditioned engine would be the ear of an old school mechanic........
Thanks @vanorak I think I was getting excited with all this talk on other threads of electronic ignitions :-0
Thanks @zed looks like a job for the techenders weekend. As everything else is working great would you just change the points for a electronic module? I guess I can then upgrade other bits later if & when req'd. Accuspark, powerspark or another? @vanorak the coil is an old blue Bosch, if that's OK, the link is far too technical for my simple mechanical brain particularly at this time of night
