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Hi @Dan Maynard yes possibly, it was strange that the plug was sparking when not fitted. Would have expected to see it cut the spark even when ground.

Hi @spudulike exactly, it was misleading hence why I never changed the fuel solenoid at the beginning. Thanks again

Hi @Stubby I think it will be my compression tester as it certainly feels like it has good compression. My arm was hanging off from pulling it over. Thanks again

Hi all, saw is now running. I checked the compression tester on a running saw of similar size. That also had a reading of 125psi so I was reluctant to remove the cylinder. I removed the carb and checked the boot, I could see the inlet side of the piston and it was ok. I checked continuity on the wiring harness and found no issues. After a lot of research on google I found a post from someone stating that the coil will cut the spark if it detects a faulty solenoid so I thought for £20 it was worth a try. Purchased a white solenoid and fuel filter and saw started straight away. It is very strange that there was a spark every time when pulling the saw over with the plug out but it does explain the change in note when trying to start the saw, one second it sounds like it’s about to fire then it sounded different as though there was nothing at all. Anyway it’s a mystery solved, thanks to everyone for there help and I hope my update may help someone else.

I will do as soon as I can, Christmas has got in the way of tinkering time

Both coils are sparking, I do not think there is actually anything wrong with the original coil other then my dad not pulling it over hard enough because when I swapped them i didn’t think the new coil was sparking but after reading a few post people said pull them over quicker which I did and got a spark. swapping the coils makes no difference, fuel in the bore or through the carb air intake makes no difference. Choke on or wide open throttle makes no difference I smoke from the exhaust with a wide open throttle but it does not pop what so ever cheers

I pulled the flywheel off and key was in tact where is should be. How else could the timing be out?

Hi @spudulike thanks again for your response. Christmas has been busy so not had any more time to look further. Had swapped the plug for brand new and swapped back to the old a few times just to try it, spark is viable with both. I have tried two different types of brake cleaner just incase, I have also sprayed it on the floor and lit it with a lighter to check it ignites. I have took petrol from the tank and put it straight in the plug hole, neither petrol or brake cleaner makes a difference even with the throttle wide open. My next steps are: Check continuity on wiring harness from beginning to end. Take off the exhaust and rock fly wheel to see if there is any movement in the rings. Check compression tester on running saw to confirm the 125psi I get on this saw If non of the about show any results then it will be a good clean down and take the cylinder off. Hopefully I get a hour or two over the weekend to take a look. Thanks again.

It probably gets used once/twice a month through the summer. It’s been in use a couple of times a week since September with no problems. I would have thought if it was a fuel or carb issue then it would have attempted to fire from fuel going directly into the plug hole or brake cleaner through the air intake. Spud also mentioned that too. Thanks everyone for your help, have a Merry Christmas

Yes, my dad has owned this saw for the last 6 years and never had a problem until now. It does not get abused and only really gets used in the winter. Thank you for the wiring tips, I will check on those

Thank you @Welshfred I will take a look at that.

Thanks @Stubby I moved it in to see if it had any effect on the starting issue. I will put it back when I do some more investigation.

Hi @spudulike thanks again for your extensive response. I will check the compression over Christmas with another saw. I understand what you are saying regarding the two types of compression testers. I have had the flywheel of and the key is fine and still in tact. I will have a look at rocking the flywheel to see if there is movement in the rings. The coil I removed has the markings 1141 4700 C The new coils is marked with 1141 4701 D (the packaging says 1141 400 4732) I did give L&S engineering the serial number and this is the part the recommended Both coils have the same issue, I did a continuity test between each section but need to do beginning to end. With the throttle wide open I am getting plenty of smoke with every pull, when I remove the plug I am getting smoke coming from the plug hole so it is definitely trying to fire. Thanks again for your help

Thanks @Stubby @woody paul I did have a poke at the rings and they seemed to move but given the fact we have a spark and fuel it leaves only one thing as you both say. I will check the compression tester on a running engine just to confirm it is ok. The saw needs a good clean before I strip it down so it might be a week before I come back with a update. Thanks again

Compression test is 125psi Still will not run on carb cleaner Put new coil on and closed the gap Checked the loom Could it be the rings? We have spark, air, fuel but compression feels good, and it wants to run. We are getting smoke