so i pulled the bleeder screw of and nothing comes out the top of the head. I pulled the lower rad hose off and it flow, so does the top, but i dont feel like i have any circulation. Does anyone know what this could be? also, I crank the motor and water/coolant splashes out the top but it does fire and run, and nothing is actually "Blowing" out of the top of the radiator, but it is splashing around a little, cant tell if its the vibration of the motor or actually building pressure in the rad.

I also am only getting about 80 psi on th compression test... damnit.

Apparently these bikes are pretty much junk ? seems like nothing but problems.

 

well there not junk. But I compare them too two-srtoke sleds. and my motocross bike. If you are going to ride one it might as well be modified cause the reliability is similiar, well almost. They aren't that bad it is more of a maintenance issue most of the time. but anyway. If you are mechanical they will provide far more fun per dollar than anything. I'm pretty sure my 95 xplorer will run down anything but a renegade. but with stock gearing I might have that done too. I'll let everyone know if it happens.
For me nothing is more fun then laying a licking on a big expensive fourstroke.

Yes your head gasket is fried. If you have not kept filling it full of coolant, then the hot sensor in the head wasn't working. cause sensors don't work without water. But having said that the one in the rad must have worked cause you said the fan was on.

When checking to see if the coolant pump is working. you should try and suck out of a bucket and pump into another one. The rads on these are really weird, they have both the inlet and the outlet at the top (with no themostat) so really the rad must be completely full to circulate.

I had the same thing happening, but not as bad. I put my coolant system pressure tester on. And in the first couple 200 foot blast wide open I had 10 psi showing on the gauge. Way too much. Once some water had been pushed out the air compressed some and all was fine. until it got really hot outside then it overheated.

Ya 80 psi not good either, but sounds like you got that one covered. get the head and top of cyl checked for warpage

 

Mrtwostroke, thanks for the help! Im not sure how to check the circulation or what to do if it is not circulating???

I guess Ill put new rings on it when I have the head off.... is there a guide or a how to somewhere for the head gasket? ive never done one on this bike before.


still runs decently with only 80psi compression?

I still had no coolant coming out the bleed screw on the head, and when I had the top outlet radiator hose disconnected no coolant was flowing our the top of the motor?

Also, ran this thing for several hours on sunday and even though it was pressurizing the overflow tank I never had to add any coolant and it is still full for the most part? though I dont thing it was circulating.

 

It should have 125 psi compression, don't just put new rings it. Check the piston for cracks and get a machinists to check the clearance and well you have his attention check head and cyl deck for warpage with a precision straight edge well he is at it. .0005 feeler gauge is what I use.

You won't have anything to circulate without the rad completely full. Coolant pump failure isn't very common, but water pump seals are. check your counterbalance oil. drain it and look for water.

Run it for a enough time to blow water out the overfull. Then let it sit for a few hours to cooldown completely. then pull the rad cap. If their is still pressure in there, you have problems.

Have you ever worked on two-stroke before?
This is just another one.
the gasket has a tab facing the exhaust and a UP cutout on the intake side. telling you right side up.
I can give torque specs for reassemble.
and piston clearance is stated at .003 in a stock one running a wiseco
a cast piston can be up to .001 tighter. some will say even less than .002 with a good breakin.
I have seen old polaris manuals that say .0015-.002, but new manuals say .0023-.0037.

My opinion on the oil injection is to take it off, and pre-mix.
advantage
more consistant lube, it can't fail.
premix engines always show less piston wear.
light throttle pull. replace cable with a 96 500 sportsman cable.

 

Mr two stroke, I guess I didnt know about the bleed screw on the top and ran it without bleeding after I topped off the radiator, the head is warped, took it to machine shop.

Is there a minimum thickness on the head?

it has already been shaved 6 thousanths before i got it. Can you geta thicker gasket? Or will it have plenty of room still?

 

You should be able to get it flat without taking off too much. I'm not sure how far you can go without switching to premium gas. but i could see having .010 off total not being a problem running regular gas. check the compression when you are done.
The right way would be to take the same material out of the combustion chamber area too. That would correct the compression ratio. just taking the same .010" off the squish band would be enough too get you ball park. on your compression ratio.

Mine is running 140 psi compression with a squish clearance of .080"
stock they have a squish clearance of .100"
I think mine has .030" off the gasket surface and .010" off the squish band to give it .080 clearance
I'm runninng premium just fine. mine is ported which changes the static compression ratio. so I have to take more off to get 140 psi then you will.

I'm told you can run the squish clearance down to .055". but you must need good fuel to do this. I'm still learning. but I have done my own porting and stuff myself up to this point. If you are interested in two stroke tuning read this and this for a start
2 Stroke Tuners Handbook by Gordon Jennings
http://www.kreidler.nl/artikelen/per...raham-bell.pdf

Tell them to take as little as possible. which will probably be .005.how much is it warped?
I actually haven't always used the bleed hole. for me I just fill it up. run a few min, top off. do this a few times gets the air just fine for me. the blown head gasket is introducing air

 

thanks for all the help!!!

they got it flat and you were right took 5 thosandths off. So now it have a total of 11 thousands off of it. Hopefully it still works and runs decent on pump gas.

Im not sure what the squish area is but hopefully it will be fine. Ill let you know! thanks again!

 

To check squish clearance, get piece of resin core solder. bend it 90 degrees and slip it in the spark plug hole against the side of the cyl. squish it with the piston. Pull it out and measure. It should be fine

 

so i got the head shaved .005 to true it and then got a new head gasket. Put it all together tonight and a steady flow of coolant is coming right out of the front of the head. I have the gasket on correcty, tab facing the front ( exhaust ) side and the P shaped deal in the back on the right side. Is it possible the jug is warped too? is it not tight enough? any reccomendations? I didnt use my torque wrench but i wrist snugged all bolts and then did a little more than that in a criss cross.

 

well bolts should be torqued to 18-20 ft lbs
Even if the head gasket was upside down and torqued it in a circular pattern it shouldn't leak like that. I don't think
Is it possible the deck of the jug is warped too. ya but I don't really think it would be that common. Old polaris tech mind have info on that. But I would check it and the head again. something is not flat

Criss-cross patern starting with the two side ones then front to back.