I have built several engines on the jap quads. Do any of you have any advise on rebuilding the 400 engine? My brother 400 has broken a piston I think. THANKS!

 

Well your still building a jap engine. They're Fuji built, and a piece of cake. Do it just like any other 2-cycle but retorque the base bolts after it has warmed up and cooled off completely.

 

Thanks! I guess I sould have said that I have never worked on a polaris quad. My wife has had 2 Trail Blazers and have only cleaned the filters.

 

Replace with a Wiseco piston (not a polaris one), take cylinder to local machine shop and have it honed, have them shave the head while there at it, and then send your cylinder to Bubba for porting. I think your brother would appreciate it!

 

i would say,if you doesn't plan to pipe the thing,go polaris cast piston,
go for even more further then,go wiseco for any engine mods.

 

Well, I found most of the piston in the pipe. The rod and crank are gone. The rest of the quad is rough. I don't think it is worth fixing. Anybody need a good Aeen pipe?

 

what year is it for and what type? topend or torquer?

 

How much for the engine as is?

 

I WILL TAKE THE TRANNY pm me ...

 

It is my brothers quad. I can't price his parts. PM me with an offer on the parts and I will ask him.