CunningStunt

Pull start it, and check battery voltage across terminals at idle and revved up.  If voltage does not go above battery's idling voltage, then I would start with the rectifier/regulator, then check stator/generator continuity.

Check the voltage across battery terminals while running at idle and revved up.  I have seen a lot of these issues for people being resolved if the voltage regulator/rectifier goes bad.  I am having a similar issue and have a regulator on the way as mine was not providing voltage at all while revving.  Hoping this is the fix so I can finally ride my bike.

I think the allen plug you are talking about is the TDC port for you to rotate the motor when checking compression and adjusting valves.  the vacuum lines usually go to the petcock on this years bikes because there are vacuum petcocks to theoretically only allow gas into carb when engine is running.  Most of these are bypassed when they go bad or the fuel leaks into the engine casing and mixes with oil. Just plug the vacuum lines with a threaded bolt.

I ended up buying a 2000 Qrunner 500 4x4 for a thousand bucks, wish i coulda got this one too though...lol

I thought just SAE 10w40 was sufficient - syn, non syn w/e since oil changes are frequent on smaller engines.

So, I went in, rotated crank to the alignment mark for TDC - valves appeared shut, and the rockers moved a freely on intake and exhause side of valve port.

I do not have the adapter for my compression tester to fit the small plug threads but I figured since piston was at top, mark lined up, and the rockers had some play that I was TDC on compression stroke.

Am I thinking this through correctly?  I have never done valve adj. before and when I was done, I started her up and still hear noise when getting the RPM's up there and it sure sounds like the valves or something in the top end.

I also don't want to rule out that possibly the previous owners could have adjusted the valves on the wrong stroke and gave therefore masking the fact that it may not have actually be on the compression stroke that the rockers had play for me.

run it for a bit and remove the spark plug and describe exactly what color the spark plug tip is.  This to me sounds like the carb jets and air/fuel mixture settings are just out whack

I think i need to adj. the valves as I get some engine noise from the valve area when getting on the  throttle really good.  Lower rpm;s no noise.

Any tips/thoughts?  Also, i am relatively sure that the intake valves are the ones on the top and exh are the ones on the exhaust side...just need a dummy check as I have never worked on an engine before.

Where can I find the specs on the shocks for this bike?  The OEM is like 250 bucks! Surely I can get some cheap aftermarket shocks if I knew the load capacity and dimensions...part specs are not in my service manual.

Lol, i just bought it online for 13 bucks haha

I purchased the manual - the 98-02 manual in the downloads section is not correct - the manual on that link is for 2003+

I purchased and downloaded it, but it exceeds the 100mb threshold for me to share with the forum, so please advise how you would like to proceed - i can link you to my Google drive and if you have the capability to upload it or whatever.

On 3/22/2018 at 9:24 AM, Coyote251 said:

I ended up buying the manual yesterday, so I added that to the downloads as well. It is for all Quad Runners (LT-F500F) from 1998-2002.

When I downloaded the manual its for 2003+ moodels unless i am missing something.  

I am thinking of buying the manual, clydes i think is the brand...I did find a really good vid on youtube of a dude breaking down my specific carb - which proved invaluable

I think you are on to something with the jet, i'd try to get a hold of service manual.  If you bought a kit though it should be specific to your model.

Whats the best thing to soak the carb in and for how long?

well, all i did was clean it up and reinstall the old components, i have a rebuild kit on the way and will install new jets and such when it arrives.  Thanks for ya'lls input

Not that I noticed...it was increasing idle while in neutral and rpm's kept increasing.  I am thinking its something in the carb although i cleaned it thoroughly...

Bought her sat not running, cleaned up card, bypassed Petcock, new battery, and after fiddling with manual idle screw got it to start normally.

Well, yesterday I rode her for a few mins, no issues and left it idling in neutral while I ran in my house and heard the rpm increasing so I ran outside and hopped on and drove it back to my barn.

What can cause the idle to automatically increase? I am kind of at a loss...I've googled and can only find pages about how to adjust the idle.

Additional Info,

I just checked the carb and it appears to be leaking fuel from the pilot screw just forward of the float bowl.  I did not mess with this screw when I disassembled the carb.

Any thoughts?

Hola!

I bought this baby yesterday, wasn't running - but a carb clean and new battery brought her to life and she sounds and drives like a beast.  Ugly and beat up plastics but w/e

So, the carb was nasty - like green buildup and every port possible and was clogged.  Where else should I look to clean or change fluids?  Also, anyone have the lt f500f SRV manual?  I did not see it in the SUZ forum for manuals.  What causes green buildup in carbs?  I am new to ATV's, but have at least dabbled in doing all my own auto maintenance and am trying to get the kick in the right direction as to what to service next before i ride her full time.

I do know that there is an oil leak that appears to be from the clutch cover gasket but will get under and clean it all up to confirm exactly where its leaking from.

Thanks!

2 hours ago, antisoc said:

It might be the baffles inside the muffler..they break loose sometimes..if you take the muffler off and something is rattling around..that is the problem.

 

My dad's grizzly 660 had this and it was the muffler making all the racket.

Aloha!

I am negotiating a price on what appears to be a pretty well taken care of 400 4x4.  Hes considering selling it to me for 500 bucks but he said the top end may need work due to compression only being 25 so he couldnt get it running but he has not investigated any further other than compression.  He also says he was using it last hunting season and when he tried to start it recently is when he ran into the problem

By the pics it looks used but not abused and the claim is that it wasnt used for anything other than getting around hunting camp.

That being said, what do you guys think?  Should I pull the trigger?  Are these particular year/models easy to keep running?  Thoughts?

I am mechanically savvy but never owned an atv, only ridden one my dad and I share at hunt camp.

Thanks and I look forward to joining this community!