PB
Addicted to ArboristSite
Jeff.... I would have to say what the shop told him is pure bunk. If you can't shut the saw of it is the switch...very common problem on all the saws of this family, both Jonsered and Husqvarna. Or it may well be a broken ground wire (that runs between the module and switch) The 80's 630 has a two piece ign system...the module/pickup and the coil ...no mag. When either of these items fail the saw doesn't run at all. I can't rember exactly what max rpm is off the top of my head but it is either 12,500 or 13,000 stock and I've built them to turn in the 14,500 area with no problems what so ever. Ritchening it up to bring the rpm down to 10,000 is foolish..plain and simple. it will burn tons of fuel, run poorly and you risk carbon builduip problems.....find a different shop....those guys are dim....the 630 is an excellent, well made fairly powerful saw. Just tell him to buy a new switch....
Yep. Everything he said. Is this a Jonsered dealer or do they carry a different brand? Either way I would stay clear of that shop. A lot of 630's from the 80's were running 2 thin piston rings compared to the later models with one. Running a 2 ring 630 at 10,000 rpm is asking for trouble. Those rings carbon up fast at normal operating conditions but with that much oil i can't imagine they would last long at all.