stihl ms391 ignition

[kier]

I have a ms 391 and the spark has gone , I diagnose it as the coil having given up , seems I can only get an original part from Germany at £52 .

90 odd here ,

but there is a ms361 part that looks identical (£14) , my question is has anyone fitted the 361 part on a 391

otherwise its been reliable

[harrythecat178]

£66 plus vat rrp in UK for coil, there are 2 options, change in 2013. Coil only fits MS391, or MS311, doubt very much the MS361 part will fit

[spudulike]

Parts can look the same but operate very differently, found this out on a Kombi trimmer where the Chinese unit backfired violently. Most coils trigger pretty much when they go over the coil but some have a delay built in so they spark well away from the coil and TDC.

 

No idea if it will work - up to you if you want to spend £14 to find out!

[kier]

mine is a 2011 would that make any difference

Edited January 25, 2017 by kier

[harrythecat178]

mine is a 2011 would that make any difference

You will need the older one, they are both same price

[kier]

the part arrived today and it fitted and the chainsaw now works , the spark looks a bit weak, does it make a difference what the gap is between the flywheel and the ignition unit its about 1mm at the moment

[spudulike]

the part arrived today and it fitted and the chainsaw now works , the spark looks a bit weak, does it make a difference what the gap is between the flywheel and the ignition unit its about 1mm at the moment

 

It should be set using a business card or a 5 thou gauge. 1mm is much too large and you risk having the spark fail or the ignition timing being retarded.

[kier]

It should be set using a business card or a 5 thou gauge. 1mm is much too large and you risk having the spark fail or the ignition timing being retarded.

thanks spud , I have some feeler gauges