how;s it going everyone just purchased a 96 polaris xplorer 400L I want to disconnect the oil injection and mix my gas . I have a 14 teen year old that drives it the most and it will give me peice of mind can anyone talk me through this please

 

Leave the oil injection alone!!!!!!!!!If it is working it is THE BEST INJECTION SYSTEM on any 2stroker.VEry easy to adjust and maintain and give very little problem.I tell you this from experience.If you want to worry about something make sure the 400 doesnt have a stock piston in it.That is the weak point.....the skirts WILL break.Go with a Wiesco and it is good for a long time .

 

i agree the injection would be better then pemixing. they do make a block off kit for it. you dont here of many injection pumps going bad out of the 1,000's out there running. imo.

 

If you go with a wiseco piston make sure you take the time to warm up your motor!!!!! They are a great piston but I have seen so many 2 strokes with scored cylinders because the 5 minutes was not taken to warm up BUT when warmed up they are at the top of the pack when it comes to quality, WISECO is a product you can trust.

 

[img]i/expressions/face-icon-small-happy.gif[/img] Good sugestions from all posts,but check to see if pump spring is ok and not rusted and operating properly! also keep a check on counter balancer oil to make sure water pump seals not leaking into area (milky color) This is a good engine but a bear to completely rebuild (20 year polaris tech) Would rather rebuild 2 500's than one 400 (or 350) Guess I'm getting too old and cranky!! Best of luck!

 

<div class="FTQUOTE"><begin quote>Originally posted by: old polaris tech

[img][/img] Good sugestions from all posts,but check to see if pump spring is ok and not rusted and operating properly! also keep a check on counter balancer oil to make sure water pump seals not leaking into area (milky color) This is a good engine but a bear to completely rebuild (20 year polaris tech) Would rather rebuild 2 500's than one 400 (or 350) Guess I'm getting too old and cranky!! Best of luck!</end quote></div>

Good to meet you.

So what is your position/opinion on the PISTON issue?

There seem to be many different schools of thought on this.
-Some say they are faulty and all will fail.
-Some say some were faulty and some will fail
-Some say it's not just the piston's fault... engine wear is a culprit

 

[img]i/expressions/face-icon-small-happy.gif[/img] Used wiseco for years,good pistons, little cheaper than polaris and you have a quality forged piston! I set by my cylinder bores TIGHT,with .001 clearance and run gently to seat rings before handing over to customers. INITIAL breakin critical to engine longivity! Be sure to have first tank of gas premixed 50-1 along with bleeding oil pump for air bubbles. A little smokey,but will clearout with second fill up! Good luck.

 

What method do you use to measure your bore clearance ?

Pretty interesting .

I have found absolute minumum on a 400L with a wiseco is .003"

On a modified 400L absolute minimum is about .0035" &lt;-- learned the hard way !

 

[img]i/expressions/face-icon-small-happy.gif[/img] If you have.003 clearance on cylinder bore,YOU have about .002 before you hear piston slap! I have a Boremaster and bore customers cylinders also! Even when boring 500 cylinders,I set to piston size and hone to final size! The only time I bore larger is for watercraft (between.004-.005 clearance) because of rapid expansion! No comebacks or seizures after 20 years! (Knock on wood) Piston to cylinder bore even for the 500 is very tight (.00125 if I recall correctly? The KEY is BREAKIN RUNNING (warm up for about 4-5 minutes,let cool,repeat) I do this for my service machines and instruct customers wrenchin ther own machines! Hope this helps.

 

Curious .

What does typically the bore measure after finish honeing a 675M08350 ?

Just trying to compare notes .