Timing Inverted SEM Four Stroke Ignitions

[PEZBerq]

How do you check the timing on the inverted flywheel style SEM ignitions with the stator mounted on the ignition cover? The stator can be adjusted by rotating it using the slotted holes in the ignition cover. How do you know where to set it?

 

[84scrambler]

Do you know what the manual says it is set at ? something like 2 mm btdc, You will need a spark plug dial indicator . Just screw it in the plug hole and find top dead center then put it to where the manual says and thats where you want your ignition to fire , so you would have loosened your screws so you can turn the entire assembly with something in the little round hole (locking the entire assembly together) and when you have it where the manual says according to the dial indicator you will tighten your screws down and remember to pull out the tool you used to lock them together. Hope this makes sense ?

 

[PEZBerq]

Makes perfect sense but sounds like the technique for a Motoplat. The SEM does not use the tiny hole setup. It uses markings but when the stator and flywheel is inverted you have to time it without taking off the ignition cover. Is it just a case of set it in the middle of the slots and forget it?

 

[rwgregory]

Makes perfect sense but sounds like the technique for a Motoplat. The SEM does not use the tiny hole setup. It uses markings but when the stator and flywheel is inverted you have to time it without taking off the ignition cover. Is it just a case of set it in the middle of the slots and forget it?

View attachment 35358

You need to use a timing light. Hook up the timing light and start the engine and hold at a steady 1200 to 1450 RPM idle. Remove the screw at about 1:00 on the cover. That is the timing mark hole. The timing mark should be visable thru that hole. If it is not visable loosen the 3 screws on the cover and adjust until the timing mark is seen in the center of the inspection hole. When you get the timing set, use loctite on the 3 screws and tighten them to 8 foot pounds,(12Nm).

 

[84scrambler]

yes, sorry pez. I seen that you ask for the four stroker sem after I hit the post button . sounds like your close tho, good luck.

 

[PEZBerq]

Thanks for the replies guys. Appreciate fellow Husky tragic helping me out. I will give the timing light a go but peering down a tiny screw hole looking for a timing mark is got to be a challenge .

 

[Michel Dufayard]

The 510-83 manual says the advance is 42.5 mm ( 35°) on the normal flywheel.
The 510-84 manual says : when the stator is in the middle of the
adjustment 35° advance is obtenaid. ( with the 3 screws).
Then do like rwgregory said with the timing lamp, if you want to check.

 

[PEZBerq]

Ah ha....set it in the middle of the slots. Thanks for the info Michel. I will try to check with a timing light still.

 

[Michel Dufayard]

http://www.cafehusky.com/threads/vintage-husqvarna-1984-4t-motor-workshop-manual.11388/

 

[PEZBerq]

Just found the 87 LC model runs its ignition timing at 33 degrees BTDC and not 35 degrees. The timing hole in the ignition cover has been moved accordingly from the earlier air cooled models. Since my flywheel has zero timing markings on it from the factory I have had to apply them using paint. Will test it out tomorrow. I wonder if the stator will be in the middle of the slots still? Thanks to all.

 

[RUF]

Hey guys...
Let me tell all of you that this Forum is much much better than any University on the Globe ...
Thanks to everybody !
Every time I read a new techical thread I understand how much I have to study more .....
....

 

[PEZBerq]

Finally got around to testing the timing. A pain to try and shine the timing light down the tiny 6mm hole plus try and see what is going on at the same time. Had to rotate the stator fully clockwise in the slotted holes to get it right.