2003 Suzuki Eiger 400 starting difficulties

[Sled Dog]

Hello Team!  Hopefully someone can help me.  I've been to the Suzuki forum and its pretty dead.  I should have been on this site a while ago as I own a Canam, Hondas and a RZR!

Anyways issue is the ATV won't start.  Friend gave it to me to try get running.  They installed a Amazon carb and machine did the same thing.  This machine has 1100 miles and is not beat.  Appears to have led a gentle life.

So the first thing I did was ask for the original carb.  They do have and brought it over.  But first I changed out all the old gas and put new in.  Got it to start but would not idle.  But could ride it around yard.  Its a manual, went through all 5 gears.  Runs like normal but would not idle.

So I got a Shindy rebuild kit and rebuilt the original carb.  Reinstalled and almost the same thing.  Starter spins and it tries to catch but doesn't until it does.  Then it seems to run ok.  Idles high but after a while it will go down.

So I take tank off and give a very good cleaning.  Took off the fuel petcock.  All looks good.  No fuel in the vacuum line so I believe its working as it should.  Cleaned carb again.  Adjusted valves.  Did not need.  Reinstalled everything and same exact thing.  Spins like a maniac for 10 or more seconds before it will start.

Spark plug is black.  Brand new one too.  I checked the spark and did not see any.  Googled how to do it and I was doing it right, tried again, now I have spark.  Hmmm.  Kept checking and always had it.

My battle plan now is to clean the Amazon (Chy-na) carb and install that one.  If it does the same exact thing I'll figure its not the carb.  If it does something different this will tell me nothing as I don't trust the Amazon carbs!

But now I've read that these models Eigers have issues with the fly wheel magnets coming loose.  And affecting spark.  Anyone know if this sounds right?  Maybe if the spark is out of time it makes it harder to start but once started the running engine can overcome that?

Oh yeah, compression is 130, spec is 142.  Not sure I trust my Harbor frieght compression tester though.  I'm bringing it to work to get the gauge calibrated.

Sorry so long winded but I like to give all the details I can for the people in the know!  Anything anyone can suggest I do?  Thanks for your time!

Edited April 27, 2020 by Sled Dog

[MarkinAR]

Have you checked the air fuel screw to see how its adjusted? Black plug is rich and given it's hard to start I'm betting it's over fueling trying to start. Chinese carb doesn't prove much bc they are so poorly set up sometimes they just won't run. Could also be valves slightly tight or timing a tooth off. 

[Sled Dog]

Thanks for the reply!  I have it adjusted 2.5 turns out.  I've also had it adjusted all the way in and it runs the same.

What puzzles me is when its running, it runs strong through all RPM.  But its hard to start.

[Sled Dog]

So today I put the Chy-na carb in. Same thing but worse! Would turn over fast and only start if you gave it throttle. More throttle than you should have to. Would not idle at all. 

So I put the original back in. Same thing, hard to start, have to give throttle but now it idles. Rode it around yard through all the gears, full throttle 5th gear, plenty of power. 

I don’t know what to check next! I’m kinda at a loss. Not sure if it would run so well if the flywheel magnets are loose. battery holds charge. All lights work fine. Don’t want to tear side of motor off for no reason. 

Frustrated...

[MarkinAR]

Did you use the same choke plunger for both carbs? I don't remember if that carb has a cable and plunger or what. Is the choke part of the carb?

[Sled Dog]

Yes it is part of the carb. It unscrews from carb and there is a needle.  I think it has been replaced. The ATV will start with no choke. But hard!  Even when engine is warm it starts hard. The choke appears to slide and move as it should. 

I don’t mind taking things apart but I don’t know what to take apart or check!!!

[MarkinAR]

Timing would be my next thing to check. A tooth off can cause the issue. 

[Sled Dog]

I'm starting to think its something like that.  Would it still run ok with the timing off?  Is this difficult to do?  I have no idea!

[MarkinAR]

Timing being off can cause all kinds of issues. My son's 300 would run perfect up to 60% throttle and then die off. Timing was 2 whole teeth off. Pretty good chance it's off and causing the issue. That is assuming you adjust valves correctly to spec.