Need help!

[bigredder]

Hey guys, I have a mid 80s Polaris Indy 400 liquid cooled that has a fresh top end rebuild and new gaskets but will not run correctly. Plugs foul easily, it has a low end bog and a top end bog as well. Mid range is okay but it is driving me crazy having no power. I want to be able to hop on it and rip across a field just like all of my other sleds. Any help and advice would be greatly appreciated! Thanks.

[shovelryder]

New reeds? Fuel pump and filter get rebuilt? Carbs got rebuilt and synched properly?

[bigredder]

New reeds? Fuel pump and filter get rebuilt? Carbs got rebuilt and synched properly?

Yes. I don't believe it has reeds.

[shovelryder]

My bad on the reed part.......Sounds like a state of tune carb issue for sure though.

[bigredder]

My bad on the reed part.......Sounds like a state of tune carb issue for sure though.

That's what I thought too but I've done everything I can think of. Needless to say it's for sale haha

[86 350x]

Crank seals? Did you pressure test the bottom end?

[russ98atc]

Crank seals? Did you pressure test the bottom end?
+1 for crank seals me and my buddy rebuilt his older Indy and could never get it running right no matter how we jetted/tuned the carbs. It was doing the same thing as you say yours is, guttless bottom end and top end. As 86 350x said definitely test the bottom end.

[Xfile]

+2 for crank seals.....if you are planning a leakdown test on 30 year old crank seals then you have already answered your own question...it needs them. You don't need to remove the top end again however. Pull the engine, remove the clutch, flywheel, and stator. Then you can remove the lower crank case half, lift the crank up a bit, removed the old seals, slide the new seals on and re-seal the case halfs.

[John Tice]

Spray soapy water & look for air bubbles. Do you trust your machine shop; did you check your cranking compression? Air Leaks
This type of question goes out on most every rebuild. If you’re a regular reader you should already know what to do. :wondering

John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

[Gearheadtom]

How's the clutches? Very well still good be a motor related issue, but clutches often get overlooked.