lurkalot

I use one of these Stihl ones, 5910 890 2420 Genuine Stihl 8mm Tee Spanner | Garden Hire Spares Pretty cheap but seem to last very well.

Haven't seen the short engines on L&S. I was surprised to see it listed in the Stihl parts list, but I need to double check it was a BR600. I'll do this when I go into work tomorrow. The price was a no brainer though compared to putting parts in it. Some say this fault is down to the nozzle waring and it putting excessive load on the engine making it run extra hot. The one I have in the workshop has hardly been used. It was seized absolutely solid and only because of the small end.

Don't bother putting parts in it, the cost as you say is pretty horrendous, especially as Stihl do a whole replacement engine for them and at fraction of the cost. I have one in at the moment which has done exactly the same thing as yours, a very badly seized small end.

If the saw has a shouldered bar stud make sure it hasn't come unscrewed slightly, that will cause the bar to leak oil down the back of the bar instead of through the oil hole.

Blower 1: Also check the exhaust outlet isn't blocked, or a lump of carbon blocking the outlet. It does happen believe me. Blower 2: What Spudulike said above.

Well while the carb is off, just remove the pump diaphragm cover, the one on the bottom held by one screw, and check the Diaphragm anyway.

Common problem on these machines. While it sits around, the gassing and changes in temp pushes the fuel slowly out of the tank via the pulse hole and fills the crankcase. Check the pump diaphragm, that's usually the cause of the flood on these, not the needle. It'll probably have a line of tiny holes down one side, if you hold it up to the light.

Absolutely agree with you.. At least I didn't say the starters were any good.

Exactly why I'm saying the carb needs proper cleaning. Did you leave any fuel in it from last season? As I'm not 100% sure what carb you have on there, posting a pic would help. I doubt it has a diaphragm though. Usually primer on one of these would just push air into the float bowl, and that induced pressure pushes a small amount of fuel up the main jet for starting. It's running far too lean which is why you have to keep priming until it warms up. Cold engine needs more fuel to run than a warm one.

Carb just needs a proper cleaning is the problem. Give it a clean out and always use fresh fuel.

STIHL do. MS-171 MS-181 to name two of them. They tear out if overtightened, or will unscrew with the nut. STIHL even do a oversized threaded stud to replace the ones that have ripped the thread out of the plastic engine housing.

Pretty common fault on these, especially if the machines left on the back of a pickup truck and gets wet. the sleeves in the ends of the shoes rust and seize solid so the shoes won't move. Press them out and clean and lubricate them.. And bolt it back together. Word of warning, be carful removing the sleeves as it is possible to break the shoes etc if not supported properly.

Probably a daft question, but are you sure it's actually leaking oil, and not just draining off the back of the chain cover after use? If it is leaking, it could be the breather valve behind the bar mount.

Or a genuine Chinese one from here, https://www.lsengineers.co.uk/switch-shaft-for-stihl-ms170.html

Blocked exhaust perhaps. Check muffler and exhaust port.