McCulloch Pro Mac 850 ignition failure need replacement components

[MrPontiac]

Hi all

I’m a 61 year old farm kid, for now looking to see if anyone can be of assistance to help me resolve and early electronic ignition model McCulloch PM 850 failure

No spark, died while finalizing yearly firewood processing, coil and electronic trigger are 2 separate components, combo components that so fa seem available to not allow for correct timing

Kill switch lead checked and not the culprit

Please if anyone can offer help, assistance, direction It would be greatly appreciated, it’s a great saw @ 82cc, I run a 32” bar -n- Chain and seems to do great, and I’m not looking forward to the potential cost of a now days replacement

Thank you
Christopher
SW Washington State
(360) 270-9636

 

[stihlaficionado]

Hi all

I’m a 61 year old farm kid, for now looking to see if anyone can be of assistance to help me resolve and early electronic ignition model McCulloch PM 850 failure

No spark, died while finalizing yearly firewood processing, coil and electronic trigger are 2 separate components, combo components that so fa seem available to not allow for correct timing

Kill switch lead checked and not the culprit

Please if anyone can offer help, assistance, direction It would be greatly appreciated, it’s a great saw @ 82cc, I run a 32” bar -n- Chain and seems to do great, and I’m not looking forward to the potential cost of a now days replacement

Thank you
Christopher
SW Washington State
(360) 270-9636

May want to pots this in the Chainsaw Forum, you'll get more views.

There is also a subform "Stckie" on Macs.

Welcome to AS

 

[pioneerguy600]

Moved to chainsaw.

 

[Jethro 2t sniffer]

Ask in the Mac thread but pretty sure you can put a regular electronic 10 series coil on it. Or find a 610 in the trash can and fleece its coil and clutch then return it to the bin

 

[heimannm]

You can use the one piece ignition unit from the 10 Series or 600 Series saws as Jethro has pointed out above. McBob worked in the Australian McCulloch plant and said they took all of the two piece ignition saws back (SP81E & early PM850 models) and installed the one piece ignition.

Max (Knightmax) and I both have NOS versions of the last issue of the electronic ignition modules available or you can find them on eBay. PN 223708, the kit comes with a long lead so it will fit either the 10 or 600 Series saws, you have to cut it to length and put a little RTV or similar sealer on the wire when you screw it into the coil.



This is the older electronic ignition coil (module), both this 95273 and 223708 bolt right on. This is an SP81E that was originally fit with the two piece ignition. In fact, it has the two piece ignition currently installed as it sets in my display.



https://www.ebay.com/itm/2954390263...zv3eYMPDmYJAZkq9YXbci5D1fQ5e|tkp:BFBMxKPXnaZj
Mark

 

[MrPontiac]

You can use the one piece ignition unit from the 10 Series or 600 Series saws as Jethro has pointed out above. McBob worked in the Australian McCulloch plant and said they took all of the two piece ignition saws back (SP81E & early PM850 models) and installed the one piece ignition.

Max (Knightmax) and I both have NOS versions of the last issue of the electronic ignition modules available or you can find them on eBay. PN 223708, the kit comes with a long lead so it will fit either the 10 or 600 Series saws, you have to cut it to length and put a little RTV or similar sealer on the wire when you screw it into the coil.

View attachment 1146674

This is the older electronic ignition coil (module), both this 95273 and 223708 bolt right on. This is an SP81E that was originally fit with the two piece ignition. In fact, it has the two piece ignition currently installed as it sets in my display.

View attachment 1146675

https://www.ebay.com/itm/2954390263...zv3eYMPDmYJAZkq9YXbci5D1fQ5e|tkp:BFBMxKPXnaZj
Mark

Hi Mark

In looking at the mounting positions between the original center 1st gen ign trigger in the pic above vs the replacement 1 pc coil/trigger your offering, the timing appears to be incorrect ?

I’d love this if I’m incorrect to get my saw running again

 

[heimannm]

I've had the original two piece ignition, and the later one piece ignition as shown above on the same saw and it ran well with either. The later one piece had a stronger spark, and has some advance built into the electronics. I don't remember if the two piece had any advance or not.

McCulloch did not have different flywheels or another trigger mount location for the models with the two piece ignition.

Mark

 

[MrPontiac]

Hi Mark

In looking at the mounting positions between the original center 1st gen ign trigger in the pic above vs the replacement 1 pc coil/trigger your offering, the timing appears to be incorrect ?

I’d love this if I’m incorrect to get my saw running again

I found a 24 fin flywheel with the Keyway offset that allows for proper timing with the new one piece ign thank you

 

[MrPontiac]

Hi all

I’m a 61 year old farm kid, for now looking to see if anyone can be of assistance to help me resolve and early electronic ignition model McCulloch PM 850 failure

No spark, died while finalizing yearly firewood processing, coil and electronic trigger are 2 separate components, combo components that so fa seem available to not allow for correct timing

Kill switch lead checked and not the culprit

Please if anyone can offer help, assistance, direction It would be greatly appreciated, it’s a great saw @ 82cc, I run a 32” bar -n- Chain and seems to do great, and I’m not looking forward to the potential cost of a now days replacement

Thank you
Christopher
SW Washington State
(360) 270-9636

Solution found, updated 1 piece coil and 24 fin flywheel replacing original 12 fin flywheel to allow for correct timing

 

[heimannm]

The timing of all four 10 Series flywheels is the same; RH start, 12 fin, 24 fin, and the 18 fin from the 82cc PM800 series saws. Have a close look at the location of the keyway in relation to the magnets.

Mark

 

[Chainsaws928]

Hello fellows,

I have most , the 10 series points and electronic ignition, and the mc-brick series with one 655 with the aluminum air filter cover pro version; some pro mac 700s, even a vintage 550 super; i really like vintage quality made in the USA 2 strokes. they are my favorites and many of you guys love them too. . I am familiar with the bolt pattern for the points style coil and the electronic style coil. bolt pattern is different. Is there a way or a part number that i can get an electronic coil that bolts to older points saws? the electronic coils have the 2 bolt holes on a single plane. the points style has one bolt hole one the top, and the second on the side. Do i have to put it in a drill press and drill the other hole to fit it into an older saw. I have used those cheap chips and they las a year and junk out.

I have read of the mysterious stickies and i can't find them or know where they are.
The Mcculloch Wizard, "Heimannm" knows what i am asking.
I would bet money he knows what to do.

 

[heimannm]

McCulloch did a nice job of transitioning from the points to electronic ignitions as all saws can use the same flywheel (magnet position).

All of the earlier saws were set up for the points coil only.



Some of the blocks during the transition from points to electronic had the mounting bosses for both types of coils.





The latest issue saws were only equipped for the electronic ignition coil.



If you want to convert a points saw to "electronic", the only practical way I know of would be to use a chip. The location of the mounting bosses do not allow you to physically put the electronic coils on a points saw. The second mount (closer to the crankshaft) occupies the same space where the body of the coil would be.

Check with Knightmax on chips, he seems to have a source for more reliable parts.

Maek