MicroSquirt.com read only forum (Jan.15,2018)

Hi
I have just completed my Microsquirt install and had the plugs firing a good spark ( but slightly erratic) but the rev counter was all over the place , from 1000 to 9000, so I noticed that it was set to "dual tach input" so I changed that to single crank wheel input (I'm using a 36-1 wheel) now I have no spark at all and I notice the rev counter is not picking up anything as well. I changed the settings back but still no joy , any ideas.
Many thanks.

I have checked the runout on the trigger wheel and its around 0.15mm , is there a definitive number for runout or should it just be as accurate as possible ?
The synch status seems to sit at 1 occasionally swinging to 3 and then 0 is this a clue?

do you have rpm when cranking engine over ? whats this on setup details would help also.

Isaacson06
I have zero rev's when cranking ,I think it has to be the trigger setup I'm just a bit confused as to why I would have spark and then loose it without touching any of the hardware.
Sorry for the vague info when I get home at the weekend I will try and swap the VR wires over and do a datalog and postit up.
Thanks

I have tweaked the trigger wheel/VR sensor setup and I'm delighted to say I have good synch (3) cranking revs around 350rpm and a spark, however the dwell now shoots up to 6,3ms even though I have set it to 3,2 ? So this creates a very week spark (I assume).
I'm busy trying to sort out a datalog but I don't have the viewer on the pc so as soon as I get that loaded I will post it up.
Thanks guys

Don't worry about the dwell until the engine is idling, then if it is still way off from where you set it, that would be something for us to look at. A longer dwell won't hurt spark. It would hurt the coil if left on a long time, but at cranking it is off most of the time (very low duty cycle) unless a ridiculous value is set.

I have fitted the carbs on today and tried to start, I'm getting some bangs through the exhaust so there is signs of life, however when I take all the plugs out and earth them and then crank it ,it appears to be sparking the 2 plugs on "ign out 1" at twice the rate of the other output. I'm also not getting any advance at cranking speed.
I've set the max cranking speed at 450 (actual is around 325). I'm running spare spark through a module and firing 1&4 and 2&3.
Any ideas?

I just noticed today that coil 2&3 are getting very hot if I leave the power on.
A quick update , on closer inspection it appears that 2&3 are firing every90 deg and this is why the coils are getting hot.
I swapped the outputs over from 1 to 2 as I wasn't sure if the first tach event was corresponding to number 1 firing and she's actually trying to run now but I'm getting some really bad kickbacks which I presume is from 2&3 firing too much.

I ha e taken off the trigger wheel and had the engineer true it up in the lathe, I reffited it and now it achieves synch almost instantly however the same fault is occuring. I tried playing with some settings like "skip teeth" but no matter what value I put in (I tried 9,36,18) it makes no difference whatsoever the plugs still fire at the same rate. I can't understand where its getting a tach signal from.
I'm struggling to get a datalog saved but im not sure if this will help as everything looks great when cranking, synch straight away,revs reading perfect etc.

Ok if you have sync so that sync status stays at 3 and the rpm at idle is constant, matches to the rpm that you think is reasonable or matches the tach gauge and never jumps to 0 or a value you know is wrong, then you re very likely past the hard part. To help further it would be best to post an msq so we can see what code you are running and how you have it configured. In this stage we want to establish that the sparks on each cylinder are each firing the correct number of times per engine cycle and more importantly are firing at the correct times.

Hi Grippo
I found something interesting tonight. I have been using my old PC so far as it has a old style connection port. I have been having problems communicating with my laptop but I persevered tonight and established a good link with the lapyop but it appears that I'm getting two different settings between the two. Under general settings of fuel setup I have the opyion of
"Spark/fuel Offset Cyl" and this is on 6 , when I try and change it to 4 it aways goes back to 6 even after a reboot, now on the PC I dont get this option?
Very confused now.