So I recently had my sportsmans 335 engine stop running on me. Parts are a pain to find, and while I have found availability on a new piston, rings, and bottom end bearings, I would rather swap the motor out. I Found a 2005 Sportsman 400 engine for sale that I would like to install in my wheeler. It looks to me, that I would be able to put my stator, flywheel, clutch, carb, etc on to mine, fit a radiator in it, and be okay? From what I understand the smaller 34mm carb on my 335 is the same as the one on the 400, but the stator is different for the 05 400 motor. What im not sure is, is it only different as far as the wires coming out of it, or is re-using my stator and flywheel going to frig with the timing? Aside from that, the only wiring thing left would be the temp sensor and I could just wire that to a temp gauge and install that in the cluster.

I know, I could just 'sell it and buy a 500' but Its fairly hard to sell an ATV without a running engine, and the ATV is in almost new condition with many extras like new tires, new winch, all new suspension, cv shafts, etc, and I picked it up for almost nothing. Any help would be appreciated!

 

It can be done as the engine mounting is similar, but you'll need to remove the oil cooler,add a radiator and hoses, you'll need the complete 400 harness,stator for the 400,an oil tank and cdi,regulator as they probably all will be different than the 335 except for the ignition coil.Might be just as cheap or cheaper to rebuild the 335 and sell it as you've addressed a lot of suspension upgrades already.Plus to be honest with you'd probably be able to sell quicker it in it's original state as a running 335 Sportsman rather than a cross breed. A lot of people shy away from alterations like this. Plus if you do have the title it should say it's a 335 as that means a lot to people even though the frame # is really what's important.As a last resort if you didn't want to tie up any more money in it,the plastics,tank,tranny,seat,suspension may work on other models and parting it out could be profitable. Just a thought on this last one.

 

Thanks for the response. Im not looking to put in a bigger motor for more power, its just whats available for sale..In my area they are NOT selling for the $1200-$1400 price range they are listed for, and 500's go for a lot more than that. What is different between my ignition system? Would it not bolt up? I was under the impression that the major differences were bore/stroke, different cam as well as a different head. Would my 335 Clutch work? Thanks!

Edit: would a 2002 sportsman 400 engine work any easier? The ignition system parts list seems to match up between the 2002 400L, and 2000 335, and not an 05 400L. but looking at the two motors they are identical between 2002 and 2005.

 

The problem is that your cdi is a different part number versus the 2005 Sportsman 400 cdi and this is for a reason.Same on the stators. The timing curve and electrical advance would be different on the two engines. You cdi is part #3085639 and doesn't show to include the 2005 model 400 on the usage chart. Same on the 2005 400 cdi part#3089238. Doesn't include any 335 model. The 335 was basically an engine unto itself and that's why I said the harness may not interchange along with the other components the 400 engine uses, unlike what the 400 does share with other machines.You either need to keep it all a 335 engine OR change it completely to a 400 which is a lot of work.



Usage : 3089238 (2005 Sportsman 400 cdi)

Year Product Model Assembly
2014 RGR RANGER 4X4 400 ELECTRICAL, IGNITION - R14RH45AA
2013 RGR RANGER 400 MIDSIZE ELECTRICAL, IGNITION - R13RH45AG
2009 ATV SCRAMBLER 2X4 INTL ELECTRICAL, IGNITION SYSTEM - A09BA50FA
2009 ATV SCRAMBLER 500 4X4 ELECTRICAL, IGNITION SYSTEM - A09BG50AA
2009 ATV SCRAMBLER 500 4X4 INTL ELECTRICAL, IGNITION SYSTEM - A09BG50FA
2009 ATV HAWKEYE 300 2X4 ELECTRICAL, IGNITION SYSTEM - A09LB27AA
2009 MIL RANGER 2X4 500 CARB ISRAEL ELECTRICAL, COMPONENTS - M09RB50MA
2009 MIL RANGER 2X4 500 CARB ISRAEL ELECTRICAL, IGNITION SYSTEM - M09RB50MA
2009 RGR RANGER 2X4 500 CARB ELECTRICAL, IGNITION SYSTEM - R09RB50AF
2009 RGR RANGER 2X4 500 CARB ELECTRICAL, SWITCHES and ECM - R09RB50AF
2008 ATV SCRAMBLER 2X4 INTL ELECTRICAL, IGNITION SYSTEM - A08BA50FA
2008 ATV SCRAMBLER 500 4X4 ELECTRICAL, IGNITION SYSTEM - A08BG50AA
2008 ATV SCRAMBLER 500 4X4 INTL ELECTRICAL, IGNITION SYSTEM - A08BG50FA
2008 ATV SPORTSMAN 6X6 ELECTRICAL, IGNITION SYSTEM - A08CL50AA
2008 MIL RANGER 2X4 500 CARB ISRAEL ELECTRICAL, IGNITION SYSTEM - M08RB50AA
2008 MIL RANGER 2X4 500 CARB ISRAEL ELECTRICAL, SWITCHES and ECM - M08RB50AA
2008 RGR RANGER 500 2X4 ELECTRICAL, IGNITION SYSTEM - R08RB50AA
2008 RGR RANGER 500 2X4 ELECTRICAL, SWITCHES and ECM - R08RB50AA
2007 ATV SPORTSMAN 6X6 ELECTRICAL - A07CL50AA
2007 ATV HAWKEYE 2X4/4X4 INTL ELECTRICAL - A07LB27FA/LH27FB
2007 ATV SCRAMBLER 500 2X4 INTL ELECTRICAL/TAILLIGHT - A07BA50FA
2007 ATV SCRAMBLER 500 4X4 ELECTRICAL/TAILLIGHT - A07BG50AA/FA
2007 ATV SCRAMBLER 500 2X4 INTL ENGINE, MAGNETO - A07BA50FA
2007 ATV SCRAMBLER 500 4X4 ENGINE, MAGNETO - A07BG50AA/FA
2007 ATV SPORTSMAN 6X6 ENGINE, MAGNETO - A07CL50AA
2007 MIL SPORTSMAN 6X6 MV ELECTRICAL - A07CL50MA
2007 MIL RANGER 500 2X4 CARB ISRAEL ELECTRICAL/BATTERY - R07RB50MA
2007 MIL SPORTSMAN 6X6 MV ENGINE, MAGNETO - A07CL50MA
2007 MIL RANGER 500 2X4 CARB ISRAEL ENGINE, MAGNETO - R07RB50MA
2007 RGR RANGER 500 2X4/4X4 ELECTRICAL/BATTERY - R07RB50AA/RH50AA
2007 RGR RANGER 500 2X4/4X4 ENGINE, MAGNETO - R07RB50AA/RH50AA
2006 ATV SPORTSMAN 6X6 ELECTRICAL - A06CL50AA
2006 ATV SCRAMBLER 500 4X4 MAGNETO - A06BG50AA/FA
2006 ATV SPORTSMAN 6X6 MAGNETO - A06CL50AA
2006 RGR RANGER 500 2X4/4X4 ELECTRICAL/BATTERY - R06RB50AA/RD50AA
2006 RGR RANGER 500 2X4/4X4 MAGNETO - R06RB50AA/RD50AA
2005 ATV ATP 500 4X4 ENGINE MOUNTING - A05JD50AA/AB/AC
2005 ATV SCRAMBLER 500 4X4 MAGNETO - A05BG50AA/FA
2005 ATV SPORTSMAN 6X6 MAGNETO - A05CL50AA
2005 ATV ATP 500 4X4 MAGNETO - A05JD50AA/AB/AC
2005 ATV SPORTSMAN 400 MAGNETO - A05MH42AB/AG/AH
2005 ATV SPORTSMAN 500 HO/INTL MAGNETO - A05MH50AB/AC/AG/AH/AL/AT/FB
2005 MIL SPORTSMAN 6X6 MV ELECTRICAL, IGNITION - A05CL50MA
2005 RGR RANGER 2X4,4X4,6X6 ELECTRICAL/BATTERY - R05RB50AA/RD50AA/AB/AC/AD/RF50AA/AB
2005 RGR RANGER 2X4,4X4,6X6 MAGNETO - R05RB50AA/RD50AA/AB/AC/AD/RF50AA/AB
2004 ATV A04BG50AA SCRAMBLER 500 4X4 MAGNETO - A04BG50AA/FA
2004 ATV A04CH42AQ SPORTSMAN 400 MAGNETO - A04CH42AQ/AR/AS/AT/AV
2004 ATV A04CH50AQ SPORTSMAN 500 MAGNETO - A04CH50AO/AQ/AR/AS/AT/AV/AW/AX
2004 ATV SPORTSMAN 6X6 MAGNETO - A04CL50AA
2004 RGR RANGER 2X4,4X4,6X6 ELECTRICAL/BATTERY - A04RB42AA/A04RD50AA/AB/AC/A04RF50AA

 

Thanks for the response, opt. I understand the part numbers were different, I am just not sure what the differences were, and my biggest concern was the timing. From my repair manual of the 335,400 and 500 it shows the only differences being bore, stroke, cam, and the heads are different, but they are all a fuji heady duty engine. Not trying to say you are wrong, as I have not worked on polaria before but do have quite an array of mechanical knowledge. It seems to me that the part numbers for the oil tank, stator and flywheel, cdi are the same as the 335 from 1999 to 2002, so I ended up purchasing a 2002 sportsman 400 motor instead of the 2005. The 05 motor had a few hundred miles on it and was the same price as the 02 that has a lot more, so that kind of sucks but I guess it's the safer bet.

 

So for an update, I got the motor in, electrical is all hooked up. Stator, flywheel and clutch fit right on so that's good. Just need to get the radiator and hoses hooked up, i'm hoping I can keep the oil cooler as an auxiliary cooler, but I don't think there will be enough room with the radiator so ill either have to ditch it, or mount it somewhere else.
The only thing I have run in to thus far is the exhaust is slightly larger on the header pipe of the 400 motor, than the 335 exhaust. I found a complete 400 exhaust on ebay for $30, but for the time being I got it to fit, ill have to use some high-temp RTV for now so it doesn't leak.

 

I interest to hear how it works out.
The only swap I seen was a 500H.O motor into a Sportsman 425. It when smooth even staying with the 425s smaller 34mm carb.

No need for the oil cooler on a dry sump since the fined oil tank acts in the same way and a oil cooler in a way.

The rad mounting holes were all there I take it since its the same Gen IV chassis.

 

Yeah we shall see. The chassis is the same, I locked up the radiator support on ebay and it looks like it will bolt right in. Not sure what you mean by, No need for the oil cooler on a dry sump since the fined oil tank acts in the same way and a oil cooler in a way." Sounds like I'll just pull the fitting off the tank, re-Teflon it and reinstall so it points back towards the motor instead of the winch and run my exhaust hose right back to the tank.. I just figured having the cooler couldn't hurt / extend the oil life.

 

Since we only sold about 3 of these things,not a heck of a lot I remember about them other than a couple customers mentioned about them not being very powerful compared to the 500. I looked deeper at the parts break down and still can't remember it having an oil cooler along with an oil tank.. Looked at all models of the Sportsman 335 and shows the tank also. Dirt Cheap Yamaha, Honda & Polaris OEM Parts & Accessories – Cycle Parts Warehouse If you can get the 400 engine running with your 335 electrical parts and adding a radiator you deserve a good pat on the back!

 

The only other thing I've run across is the temp sensor on the head, but seeing as I am using the computer off the 335, I should just be able to wire an aux. Temp gauge off that sensor, if I want to be able to read it. There is a sensor on the oil cooler that plugs in, I have to do some research to see if the machine uses that information or if it's just for a light. I'll keep posted when I get more time to work on it, I'd like to have it running by friday