View Full Version : Stihl BR420 Starting Secrets?

04-24-2007, 10:29 AM
I bought a used BR420 that runs great when it starts. It seems to be very easy to flood. Sometimes it will start cold without any choke, so that seems to indicate good condition of the engine. I usually try to start it by giving half throttle and choking until it hits and then switching choke off. Sometimes it gets flooded. Maybe I should try without choke first. Does anyone use another procedure to start when cold that seems to minimize flooding?

04-24-2007, 07:15 PM
No throttle when starting...only choke til she hits.

lawnboy dan
04-24-2007, 08:45 PM
no trottle ever when starting .hot or cold

04-24-2007, 09:04 PM
Check your air cleaner, plug and spark arrester. Most units lock on full throttle to start.

04-25-2007, 07:22 AM
Thanks for the replies. I see that two out of two say not to use throttle when starting. I guess I learned something. That is why I come to this site. Have a nice day.

Nukeman 7
06-06-2007, 10:20 PM
:usflag: All Stihl 2 cycle engines flood easily due to the design of the carburetor. If you check the owner's manual, it provides very specific starting instructions. Always use 89 octane gas, set the choke when the engine is cold and leave the throttle in the fully shut (i.e., released) position. Pull the starter cord rapidly until you hear the engine "pop" as it attempts to start. As soon as you hear the first "pop", you must open the choke or it will flood. It should start on the next tug. My dealer was very emphatic about using this technique when I purchased my BR 320. I have not have any problems in eight years of using the blower. Also, you will see a significant improvement in performance if you remove the spark arrester screen from the muffler outlet and use a 50:1 mix of Mobil 1 Racing 2T synthetic oil. It is marketed for 2 cycle motorcycle engines and air-cooled lawn equipment. You should be able to locate it an AutoZone store for ~$8 a quart.

06-07-2007, 07:06 AM
Thanks for the detailed information.