What's on your bench today?

[Nat]

I've got an FS45 (nettle scarer) on the bench at the mo.

Usual broken trigger and customer wants the muffler modding to fit a pipe on for smoking out rats!

[NI Tree]

it bloody good fun smoking out rats

[spudulike]

Had the 048 that I sold a week ago back as it had started bogging and the owner said that there was some marking on the piston.

 

I pressure and Vac tested it, seemed OK but wasn't perfect:confused1:

 

Took off the cylinder, the piston score was more of a slight abrasion, took it off with a light rub of finishing paper and gave the area around the exhaust port a light rub to finish the area that had caused the marks on the piston but it looked pretty fine to me.

 

Reassembled and again, the vac and pressure wasnt 100% but noticed the air was leaking out of the carb, turned out to be a leaking needle valve. A bit of a strip and clean and all was good:thumbup:

 

I really hate it if there is an issue with any saw I sell - Grrrrrrr

[woody paul]

Husqvarna 250 brush cutter, runs for a time then just cuts out then will not start.

[morten]

Husqvarna 250 brush cutter, runs for a time then just cuts out then will not start.

 

Possibly gunked-up tank breather valve, causing vacuum in petrol tank. Try opening the petrol tank cover to relieve possible vacuum, and see if it starts.

[spudulike]

Possibly gunked-up tank breather valve, causing vacuum in petrol tank. Try opening the petrol tank cover to relieve possible vacuum, and see if it starts.

 

Sounds a bit like that to me - just spent time on a Jonsered 625 with a blocked breather - the saw would fire and run, then go boggy and then die - was driving me mad.

[GardenKit]

As above, but if not a fuel problem check for a spark after it has stopped.

I have known coils (ignition modules) to fail when they warm up.

[spudulike]

Stihl MS390 - strange saws to work on, the top cover is sort of part of the handle assembly and airbox and is a right pig to remove:thumbdown:

 

This came in with a non existent idle and a bogging rev, cleaned the carb, checked the metering arm height, the needle valve, the diaphragm and gauze filter. Went on to check the fuel line, the filter, breather etc.

 

I then pressure and vac checked it and it has a bit of an air leak and failed both so pulled off the clutch and oiler pinion to check the crank seal that was fine so have had to get that dreaded top cover off as below - next check is a pressure check again now I have access to the carb boot and impulse line.

[Megatron]

Reassembled and again, the vac and pressure wasnt 100% but noticed the air was leaking out of the carb, turned out to be a leaking needle valve. A bit of a strip and clean and all was good:thumbup:

 

How does air leak out of the carb if you are performing a vac/pressure test on the crankcase?

[Megatron]

I then pressure and vac checked it and it has a bit of an air leak and failed both so pulled off the clutch and oiler pinion to check the crank seal that was fine so have had to get that dreaded top cover off as below - next check is a pressure check again now I have access to the carb boot and impulse line.

 

I would have removed the flywheel before removing the top cover to check the oil seal and also the sealant between the pan and the cylinder. The top cover is relatively easy to remove, harder to install. It does help if you remove the brake handle first though.

Looks like an early model, can't be certain from the pic of the date on the sticker. But given there is no decomp and the old style tank vent it looks like a 2000/2001/2002 model.