I've had my 018 for 1-1/2 to 2 years and have had increasing trouble with starting. When cold it will take up to 20 pulls to get it going. Runs well, but requires up to 5 puls to start when warmed up. My Stihl dealer cant fix the problem, Stihl rep says they should be able to get it to 3-4 pulls when cold.
Dealer says next step is an $80 carb, and that the 018, not being a pro model, is only going to last me up to two years.
(tree service, some logging and firewood. run it hard several times a week)
any thoughts?
I'm thinking about eliminating it from my stable and running my 191, 200 and then jumping to the 026, but it is my brother's preferred climbing saw and a good back-up
Your problem is quite common among owners of newer Stihls. There are some Stihl lovers who will rail on and on forever giving reason after reason why the poor performance has something to do with lack of maintenance and that your saw would run properly if only you let the Stihl certified mechanic fix it for you. But I finally gave up and went to other brands. With the exception of maybe a MS440, you couldn't give me a new Stihl. And I ran nothing but Stihls for many years.
That problem sounds kind of like one I heard somewhere where a guy had a little husky that wouldn't fire well cold or hot, and it turned out to be the choke plate was not in the right place, so full choke wasn't full, and half choke wasn't half. Saw ran good, but wouldn't start worth beans.
Check for a plugged screen in the muffler. If the saw can't get rid of the exhaust, it can't get fresh fuel mix in.
It takes a lot of running for the carburetor to get so worn that it needs replacing. Gasket leaks or seal leaks can make for hard starting too, but they usually show up as a lean running saw, or one that can't be adjusted to run properly.
Fuel pump diaphrams need replaced fairly often and can be another source of starting problems.
Bad diaphrams in the carb can also make a saw run strangely, things like not running well, not staying at one continuious engine rev speed while idling, things like that. I need to rebuild my 670 carb soon so I know that a bad diaphram can cause this .
I would be looking at everything related to fuel supply through the carb.
Proper carb and choke adjustment.
It could be a bad crankcase seal.
You can check for spark and fuel at the plug.
If the adjustments are good and fuel flow looks ok to the carb you can start with a carb cleaning and/or rebuild kit and if that doesn't work I would have the saw tested for a leaking seal.
Also, Check for dryrotted and/or cracked fuel lines too. I'll also advise checking the carb intake mounting, intake boot if it has one, and inspect the impulse line for leaks as well. Its just some more ideas for you.