The Jack's Small Engines Forum - Join Our Online Community
2024/04/22 12:05:09
Gusta

Have a Red max BCZ2500S string trimmer, goes Bang-----Bang

Starts fine then in 3-4 min. running goes bang----bang ----bang , not 4 cycling  ,then if it rests for about 4min. starts up fine again then starts the bang bang and slowly shuts off.. So i tore it down to clean it up lots of 15 year gunk, cleaned up the magnet on Flywheel and feet on coil  .. Reset the coil, gap put together , with new s/p ,and same thing bang bang shuts down ..its still got good hella compression ---- Carb rebuild or new coil ??? thanks.
3 comments Leave a comment
SRTsFZ6
Not quite sure what that sound is but when it act's up either pull the spark plug, or have a known good one handy.
 
Plug it into the spark plug wire, ground to the head/block and look for spark. 
 
Coils can fail when they get hot and then come back, a carb issue 
usually won't come and go...
 
.
2024/04/22 16:52:34
Gusta
Hello; I would elaborate, and also say the sound is also like backfiring, loading up on fuel then periodic spark , and bang bang = after about 4-6 min. running , it has good static spark test ,  your coil suspect sounds like a good answer  , checked price on new coil its around $100.00 so I guess i will look on Ebay for used..   I've actually had it for about 20 years, I just found a carb for it in my old inventory ,so I guess I changed it some time back , I have about 30 engines here on the farm, plus my vintage go-Karts (2cycle), so its hard to keep track, other than that its been trouble free .. Thanks for your time. Gus.
2024/04/22 18:32:54
SRTsFZ6
Love them 2 strokes!!!
 
Yep, you can have a coil fire when cold, then quit when warmed up.
Sounds like you lost spark, it loads up on un-burned fuel(no spark),
then when spark returns you have a loaded up engine..  
 
Also make sure your spark arrester is clear of carbon (not your current problem).
 
Please post back how it goes...
 
Scott
 
.
2024/04/22 22:15:39

Comments are closed.

Copyright © 1994 - 2016 Jacks Small Engine & Generator Service, LLC
© 2025 APG vNext Trial Version 5.5