MadfishNZ Posted August 22, 2023 Report Share Posted August 22, 2023 Hi everyone, first time tuning one of these, I have solid spark on the spark test but no spark while cranking. no engine cutouts are active, I have attached a trigger scope file, looks like on my 36-1 tooth crank trigger only 13 odd are getting picked up? if someone could have a wee look that would be great cheers also running a 1 tooth trigger off the cam fyi TriggerScopeLog22823.llgx Quote Link to comment Share on other sites More sharing options...
Adamw Posted August 22, 2023 Report Share Posted August 22, 2023 Correct, that isnt going to work. What do you have for a sensor? Does the wheel run true and have a consistent airgap for the whole crank rev? Is the sensor centred over the width of the wheel? Can you attach a pic of the wheel design. Quote Link to comment Share on other sites More sharing options...
MadfishNZ Posted August 23, 2023 Author Report Share Posted August 23, 2023 Hi Adam, thanks for you reply. The sensor is a 3 wire hall effect most similar to a rotax brand, running less than 1mm next to 36-1 tooth trigger wheel, (photo attached) seems to be consistent gap. ive got shielded wire running to the ECU and tested all clearances today and made sure of voltages at the plug for the sensor (12v supply and earth) . previously I had a link G4+ Atom but upgraded to the storm as I couldn't get wasted spark running properly on my v8 so went to sequential. I have attached photo of trigger 2 running off the cam also, thanks Quote Link to comment Share on other sites More sharing options...
Adamw Posted August 23, 2023 Report Share Posted August 23, 2023 Whats the crank sensor off? Do you have a part number or anything? Quote Link to comment Share on other sites More sharing options...
MadfishNZ Posted August 24, 2023 Author Report Share Posted August 24, 2023 The part is now superseded, but it's a bosch 0281002728 Quote Link to comment Share on other sites More sharing options...
Adamw Posted August 24, 2023 Report Share Posted August 24, 2023 I dont really see any obvious issue there. Im assuming a magnet will stick to the crank wheel (ie its not made from stainless)? The drawing on the datasheet suggests the sensor should be oriented opposite what you have, but I have never seen 180deg clocking cause an issue before - I have only seen an issue with some sensors when clocked 90deg from how they should be. And especially at cranking speed I really dont think that is the problem in this case. Looking at your crank sensor pic, can you confirm you have ground on the left pin, trig 1 on the centre and 12V on the right? Looking at your scope again, when the teeth "disapper", the voltage is sitting at zero, that means the sensor is not seeing the "gaps" between the teeth. You could try increasing the air gap more to see if that reduces the magnetic flux enough. Even just try something temporary as a spacer like a piece of cardboard or similar, I would give it about an extra 1mm air gap. If all those questions check out and more air gap doesnt solve it, then I think I wouldnt waste any more time on that sensor and just get a Littelfuse 55505 or ZF GS101201, both these will be quite an easy swap, I think the bolt hole will line up and you will just need about a just need about a 8mm spacer under them. Both of these are very forgiving sensors in terms of wheel design and air gap etc. Quote Link to comment Share on other sites More sharing options...
MadfishNZ Posted August 25, 2023 Author Report Share Posted August 25, 2023 Hi Adam, it seems the problem was the clearance, I tried 1mm and it picked up a few more teeth, then 2mm then finally 3mm (total 4mm) clearance and now picking up all teeth! thanks very much for your help Quote Link to comment Share on other sites More sharing options...
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