I did not remove carb somebody else did what is the fuelline routing for stihl ts 420?

SOURCE: hi there; my stihl ts 420 does not start easily

replace the decompression valve. also check for carbon buildup on top of piston. usually when a saw stops on its own after 5 min or so.... the piston and jug are scored and need to be replaced.

SOURCE: stihl ts 420 concrete saw screws will not come out to replace air filter

This was very common, they say it was because the screws were too long and prutruding through the nut the thread then gets covered in concrete dust and when trying to unscrew locks in the thread. You will probably have to destroy the cover to get it off.

Brad

• 425 Answers
• Posted on Aug 25, 2012

SOURCE: stihl madel ts420 how to change air filter

There are 4 torx screws on the black back cover. Here is the owners manual. It is explained on page 33.

Stihl TS420 owners manual

SOURCE: my stihl ts 760 , no gas going to carb. I have

sounds like the diaphragm in the carby is shot, Ebay sells new complete carbies for $76. Also check needle and seat, by pulling off carby and blowing in the fuel inlet while the cover plate is off. push up and down on the needle and seat, air should go through when you have it open. Good luck

SOURCE: TS 420, New carb, hot spark , good compression 85lbs, primer bulb pumps up , runs on sprayed gas in carb, wont get gas on its own ???????, what else to check, can pick up in tank be bad but stil

I'm with Andrew, 150-170 is pretty much standard for 2-cycle machines unless they're say, Stihl 4-mix, which would be much lower due to the design which incorporates valves. My guess is the saw is tired and needs a new top end kit. Remove the carb and the muffler and with a flashlight, inspect the intake and exhaust ports for wear to either the exhaust or intake sides of the piston. Any heavy carbon build up, bluing or other discoloration, or heat-transfer aluminum galling means the top end is toast. Also, while you're in there, grab the flywheel and rotate it back and forth ones the rings are in the exhaust port view. Check to see that there isn't a noticeable (use your judgement) amount of wear in the picton grooves indicating the end gap on the rings is obviously too large meaning the rings have worn out as well at the top of the cylinder, just below the ridge. I'd try to sell a new top end to the customer or offer $50-100 off the price of a new saw, with this tired trade-in that you can repair and sell to someone else. It's business my friend, one mans junk is another mans treasure. Hope this helps.