Hutzl ms660 build

[MattyF]

Turn and a quarter should be safe if there is no air leak with stihl carbs or copies I guess ? Always set mine to that.

[Mark Wileman]

8 minutes ago, EricBradley said:

all miss firing is down to ignition. Nothing else as far as ive ever seen

Thanks Eric, going to get a genuine coil and see how she goes. I've got her idling fine now, only misfiring when I put the gas on!

[dan494]

Are you using their spark plug or switched it out for a decent one? Might make a difference?

[Mark Wileman]

I'm using theres, good point, might stick a real one in

[dan494]

Yeah I didn't even bother trying theirs. Only £2 for an NGK

[Mark Wileman]

1 minute ago, dan494 said:

Yeah I didn't even bother trying theirs. Only £2 for an NGK

I can't see it affecting timing though, all it would do compared to a real one would produce a weaker spark? I have the opposite problem, too much combustion

[Mark Wileman]

Just took the exhaust off, wasn't that tight, so there could be the issue, gasket was in the right place as per parts diagram but seems it would be better sitting between the heat deflector and the cylinder, rather than between the heat deflecter and muffler? would it hurt to have two gaskets there? one each side of the deflector?

[Stubby]

2 minutes ago, Mark Wileman said:

Just took the exhaust off, wasn't that tight, so there could be the issue, gasket was in the right place as per parts diagram but seems it would be better sitting between the heat deflector and the cylinder, rather than between the heat deflecter and muffler? would it hurt to have two gaskets there? one each side of the deflector?

I have run saws with no gasket . Did not seem to make any difference . As said ignition / timing of spark ........

[Mark Wileman]

1 minute ago, Stubby said:

I have run saws with no gasket . Did not seem to make any difference . As said ignition / timing of spark ........

Just trying to eliminate all the alteratives before forking out for a genuine coil assembly

Edited January 13, 2018 by Mark Wileman

[spudulike]

6 hours ago, EricBradley said:

all miss firing is down to ignition. Nothing else as far as ive ever seen

As he says, no carb condition will cause a backfire as the backfire is caused by the saw firing once the piston has cleared TDC. Husqvarna coils can be a bit weird with how they are set with two of the metal laminates being close to the coil and the other being a fair way from the coil. Without checking, the 372 lower two should be close and set to the magnet and the upper one should be a way off the coil. Even if this was out, it would cause an uneven idle but very unlikely to cause a backfire.