# kawasaki fc420v backfiring exhaust and carb



## matcoofohio1 (Jan 28, 2007)

This is a 14 hp single cylinder motor. It is backfiring through both the carb and exhaust. I think i have checked all obvious things, checked and replaced fuel. Checked flywheel key, checked valves and cam timing good. still cant figure out why it wont start. I shut off fuel to carb and atempted to start w/ just starting fluid but same thing happens, engine cranks a bunch before backfire through carb or exhaust. also spark is good, I feel this is a timing issue as engine does not run fine on just starting fluid.. 

any help is appreciated!!!


----------



## jpasch (Oct 21, 2010)

*FC420V Backfire*

Same problem here with the FC420V backfiring through both the carb and exhaust. replaced carb gaskets and o-rings, and ignition module, no luck.

thanks for any ideas,

j.


----------



## jpasch (Oct 21, 2010)

*FC420V Backfire*

Same problem here with the FC420V backfiring through both the carb and exhaust. replaced carb gaskets and o-rings, and ignition module, no luck.

thanks for any ideas,

j.


----------



## LowRider (Dec 23, 2008)

could be carb is clogged or machine isn't getting fuel the way it should which means a clog in carb/gas line/gas filter if equiped. clean throughly and see what happens, jets included


----------



## 30yearTech (Sep 14, 2006)

jpasch said:


> Same problem here with the FC420V backfiring through both the carb and exhaust. replaced carb gaskets and o-rings, and ignition module, no luck.
> 
> thanks for any ideas,
> 
> j.


What is the spec number from your engine?

Have you checked the compression or done a leak down test?

Check the valve lash, valves that are adjusted too tight can cause this type of issue.


----------

