If it only pukes when you rev it and then it comes down in rpm,possible that it could be the cap seal leaking and into the bottle.. At least hope it's simple as that..

 

I have a 1998 sportsmant 500motor only 1,200 miles runs great. Can i transfere it into my 2009 sportsman 500 efi? Using all 09 electrical and stuff. Just wondering

 

I'd rebuild the 2009 if possible first. If it's trash,the engines can swap out. Basic difference is that the 2009 500 is an HO engine(longer duration cam,larger carb and intake manifold) which you can swap out to the 98 engine and use the 2009 harness,and electronics...SORRY reread that it's an efi,BUT the cam and efi components could be swapped,BUT will need the stator,flywheel, crank position sensor etc from the 2009 engine. Along with the efi intake,throttle body and all other efi parts..

 

Cool. Good to know i have some backup!

 

So they sent me a diff. Rad cap for 09 sportsman. Apparently they had two diff. Ones for 2009 but just changed after at a certain date. The one i got was a shorter spring to seal same 13lb though. Seems to me the older 09 system made cap maybe had problems? Which is what i have by vin.I kept the cap and ordered a new filler neck to fit it for newer 09 model.polaris parts babits shows the old cap # but the filler neck # is same for all of 09 models? I dont get it!May as well kill 2 birds w 1stone. Crossing my fingers👿

 

They do show changes after a certain date. Hope the new filler necks works ok.

 

Made a cooling system pressure tester at work 2day. Hooked it up to the line that was between the filler tube and radiator. Seemed like it would only take about 8 or ten lbs pressure and the rad cap would blow by. I checked w a digital tire gauge and pressure held was like 7lbs. Pretty sue cap or filler neck must be junk. Should know for shur tomorrow if filler neck comes in mail!

 

So i put new fill neck and rad. Cap on and that did not fix the issue. Tonight did base and head gasket with polaris oem gaskets. Before i had used a namura head gasket that came w the piston and rings. So far after letting it warm up i can rev it and it does not seem to be presurizing cooling system. So im assuming the head gasket was junk. Was not impressed w the gasket when i took it off. It was like paper cardboard coated cheap ****. Oem way better! So far lesson learned

 

Used their pistons before,but not their gaskets. We used and sold plenty of Cometic and Vesrah gasket kits with no problems.Imo Vesrah especially is as good as oem. Sorry it took that long to find the problem,but like they say,s/it happens.. Plus never liked the torque sequence on the head for the 400 and 500. If you don't do it by the book you can have problems.

 

I didnt use the sequenced directions in book for doing the gaskets. Had the cylinder and head back on all that time to do tge torque sequence and neglected to put the cam chain slider on the front in before putting the head on. Jad to undo head and retorque headbolts. Wasnt happy!