Polaris 400L (Everything I know about tuning and Re-Building the Carburetor)

In this video I want to talk about tuning and rebuilding the carburetor. I explain what to check before you start adjusting the settings and changing the jets.

[@firehades2007]

One of if not the best video i have seen on carb cleaning and adjustment. very well explained and very thorough. thanks!

[@MrFixit1]

Thanks for watching

[@davelocke2406]

Thank you that’s the first time I seen how to adjust the choke and throttle cable that’s what I needed I love your videos the best I seen so far I have 1996 polaris 400 4x4 sportsman with after market carb and was having trouble dialing it in I think I’m on the right track now watching your video thanks again

[@skiptaggart8116]

You are a great instructor. THANKS!

[@leviscott8519]

Great videos on these polaris 4x4s Brother! Very helpful! I had no idea how much tech is crammed inside these bikes! Must be worth working on.

[@Ladyinthemist]

You would be a "Great Instructor "! You explain everything so clearly. Great video! Thank you for your knowledge. 😊

[@patriksteffansson6466]

Thanks for another very informative video, also thanks a lot for taking the time to make a video about the carburetor! I removed and looked at my reed valve, there was a rather large gap on one side unfortunately, I turned the tabs and almost removed the gap. However, I have problems finding replacement parts here in Sweden. Will test drive tomorrow and see if it runs better. Thanks again!

[@patriksteffansson6466]

I have a 1992 Polaris Trailboss 350L4X4, would you say it should also idle around 700rmp?

[@MrFixit1]

@@patriksteffansson6466 My manual says 700rpm idle speed for 350 4x4

[@patriksteffansson6466]

@@MrFixit1 Thanks so much! I have ordered an RPM Gauge Meter from amazon, when it arrives I will set the idle properly.

[@adamap1]

Awesome. Im just starting to dig in to one of these. Thanks for the video!

[@mkuehn5450]

at 25:25 the chart is most of what you need to know about jetting. divide your throttle into 1/8ths or 1/4th. (bottom scale) depending where in the throttle travel you feel an issue is where the adjustment is needed. 1/4 to 1/2 pilot. 1/4th to 3/4, needle, 3/4th to full, main jet. unless you've made changes to the motor, stock sizes are best! look elsewhere for your problem. for example, i have a richness at 1/4, so i moved the needle clip to the top position. no size number stamped on my pilot makes me think an aftermarket part is the root cause. just remember, fix ANYthing else before jetting. #1 dirty carb / fuel #2 air leak.

[@Engine4dragon]

I have a question. I have a small dribble out of the float overflow tube at higher rpm. I have adjusted the tang to level. All new carb kit. Carb used to constantly flow out the overflow. Now only a drip drop. Like two drops every other rev. Is this normal. Or do I need to lower the float level.

[@MrFixit1]

In a perfect world the carb wouldn't drip a drop but I wouldn't say this is normal but not a big issue. Did you replace the needle and seat valve?

[@Engine4dragon]

Thank you so much for the reply. I have replaced the needle and seat. It is a rubber tipped needle. Followed your video 100%. The kit is an all balls kit. Seemed pretty straightforward.

[@MrFixit1]

@@Engine4dragon Try lowering the fuel bowl level like you was talking about and see if that helps. Keep in mind the less fuel in the bowel the leaner the fuel mix will be so don't go too far down. there could also be something up with the floats.

[@allenbrooks9968]

Great videos! Ive been looking for information on the 400L for sometime now. Glad i found you! I have a question...have you had any problems with the machine not going into forward high or reverse? It will operate in forward low. The linkages all move as should and at the transmission where the linkage connects is moving with the linkage but the machine will not operate in f-high or reverse. Can you help me with this issue? Again..great job! Very informative and if you're not a teacher..you would make a great one!

[@MrFixit1]

On this subject the manual says to disconnect the shift linkage from the transmission, then shift fwd rev, if the trans shifts it is a shifter problem, if not then it is a transmission problem. Try this and see if you can isolate where the problem is.

[@Kingsoupturbo]

There is a seperate rod that operates low range, high everse are on a single rod that has to be adjusted perfectly. You have to take the rear section of exhaust off to check the shift fork for H\R. disconnect the Rod and see if you can push the fork to engage H\R. The shifter also has detents in it and supposed to have oil, it might be siezed up and not working right. The factory manual has the procedure on how to adjust the H\R rod, its very tricky to get it perfect.

[@allenbrooks9968]

Thanks for the info guys. I'll check these when I get some free time.

[@DennisMarchetti-k7z]

Great video. When I start the engine cold the engine will idle but will not rev up. It loads up and may backfire. After the engine warms up at idle it will rev up and runs just fine. Any ideas?

[@MrFixit1]

Running issues while the engine is cold suggests a lean condition. I would look at the needle clip position, needle jet (emulsion tube), main jet, choke plunger, intake, head gasket or cylinder base gasket leak. other possible reasons for this if it is truly "loading up" suggesting a rich condition, the carburetor is overflowing and allowing fuel to enter the engine while the engine if off. This would take some time for the engine to clear the extra fuel out. Try running it for a bit then turn off the fuel valve while the engine is off then turn it back on again after the engine starts back up and see if the problem continues. Hope this helps.

[@SZYSZUNIA80]

I have another problem. The engine is still running after removing the key from the ignition. And after switching the button to the end engine. It is still running

[@MrFixit1]

Check out this video kzbin.info/www/bejne/anzWn4WHhLmlrsk

[@SZYSZUNIA80]

hi. hello again. can you tell me how to adjust the stator?

[@MrFixit1]

As far as I know there is no adjustment for the stator. There is a timing adjustment if that is what you are referring to.

[@SZYSZUNIA80]

hi. i'm back. i need help again. everything put together. but it doesn't want to start. how to adjust the carburetor. it smokes very badly

[@MrFixit1]

Check out this video kzbin.info/www/bejne/d4qcfJ6kqtebbaM

[@bustersmith5569]

I dont think that machine has reeds 🤔 ? Mine is the same machine no reeds ,,,

[@MrFixit1]

Yes, the 400l & 350l has a reed valve.

[@JanMicinik]

Very nice video and summary bro. I studied all of this last month, I was rebuilding top end of Polaris Xplorer 400 2000 (same engine as yours). I have a little problem with it, i tried different jettings,needle settings and so on but it still looks like running very rich. I need to put down float level lower and now it starting good, idles good, no smoke, but when I put full throttle it smokes white (grey) really bad.. I put new head gasket rebuilded water pump, It is not consumpting water I am sure. I thing it is still very rich at full throttle. What do you reccomend ? Main jet is 200 , pilot 30, needle is on the first clip (tottaly down in main jet)... I dont have any smaller jet. Do you thing maybe float level should be even lower ? Is it possible it should be like that because emulsion tube should be worn out or something ?

[@MrFixit1]

Well, if the emulation tube (needle jet) was warn it would not have much effect on full throttle. The main jet will only allow so much fuel into the engine. a rich condition usually makes black smoke not a "gray white smoke". I wouldn't change the float level because you could start running the bowl dry at long full throttle intervals. I would get a main jet kit with smaller jets and try to jet down and see if that makes the deference. It's possible the oil mix is too rich. Are you pre-mixing oil or are you using oil injection? It is possible the oil injection is allowing excessive oil into the engine.

[@JanMicinik]

@@MrFixit1 black smoke so on this two stroke engine ? Cause it was visible when float level was higher engine runs more bad.. and it smokes still "white-grey" even on idle. I changed it little bit lower and now starting,idle, 0-1/2 throttle OK, but 1/2- full throttle smoking white... I am waiting for spare throttle cable... oil injection pump is working , connected , but throttle cable to pump is disconnected and now in tank is premix 1:50L 100 octane and Motul 2stroke oil.

[@MrFixit1]

@@JanMicinik Not necessarily a black smoke because of the two stroke oil but will be dark. White smoke is usually an oil smoke or coolant steam. If the oil pump is connected and primed and working other than the cable is not connected, it is still injecting oil. When you say "1:50L" I am assuming you mean 50:1 ratio? I would install replacement cable and set up the oil pump according to the manual, (I have a video on that) Then run 100% gas in the tank and go from there. How does the spark plug look? Is it black and sooty, or oil soaked?

[@JanMicinik]

@@MrFixit1 Yes, I meant 50:1 ratio. 50 litres of gas and 1 litre of oil. Today arrived replacement cable so I put it on, adjusted and primed like on your video and in tank 100% gas. I went for a ride and after 10 minutes of riding it was still smoking bad. Today smoke looked more white-blue and smell bad like something burned...Right after ride I pull out spark plug. It is white...

[@MrFixit1]

@@JanMicinik White spark plug is signs of lean condition. I would suggest replacing needle clip to 3rd position and reset float arm to parallel to the carburetor body. Also check the balance shaft oil. It is possible the right side crank seal is leaking and burning balance shaft oil. There should be 100ml of fluid in the balance shaft.

[@midsouth2strokes185]

Where can i get the stock reeds at?

[@MrFixit1]

you'll have to search on the web here is the part number (Valve 3240064)

[@matthewmaddux8435]

Where do u get the spec charts?

[@MrFixit1]

From the manual I have.

[@gregvoigt551]

how do you leak vacuum?lol

[@MrFixit1]

The engine creates negative pressure and if it leaks it will leak atmospheric pressure into the engine and we call it a vacuum leak.

[@toddsutherland2864]

Idles but kills when I give throttle

[@MrFixit1]

Clean and inspect the carburetor. Check out my video on, Everything I know about cleaning and rebuilding the carburetor.

[@userunknown2645]

Hey I have the same carb on polaris 400 xplorer 1999. I cannot get the throttle adjusted properly. Iv cleaned several times with hx with my atv. But I cannot get this running right. Choke works correctly. Opinions?

[@MrFixit1]

May need to re-jet the pilot and or replace the choke plunger. Thats if everything else is in good working order. Hard to say for sure with such limited information.

[@userunknown2645]

Could I ask u a few questions on how to set the carb back to basic so I than can adjust from there. It seems I'm chasing a tight throttle to keep idel high enough not to stall, but still have no response on idel screw. Than when I adjust thumb etc switch to keep a small gap I mess everything back up with the previous adjustment at carb. I'm playing at 2 turns out on air screw. No response on idel screw. Only way I can keep it idel is tighten at carb side, but than the cable pulls or pushes when turning . Lots of slack in line, no pitch, no strapping, it's because I adjust cable so tight to get it to idel. It takes a while to Rev down into the 600 range but than puts puts puts and dies. Knowing this, could u please provide a direction or way to communicate. Ty

[@MrFixit1]

@@userunknown2645 I can only help so much. Use the chart I supplied in this video to restore factory settings. Check the engine for vacuum leaks and reeds for damage.