'06 Husky 510 pushing coolant out of the overflow bottle.

[tls25rs]

Tried a few other avenues to see if anyone had any input on this but haven't gotten any feedback as of yet, figured I'd throw the question out to the masses and see if anyone has some advice for me.

I have an 06 Husqarna SM510R that started to push coolant out of the overflow bottle after running a few sessions on a roadracing course in NY (NYST, pretty cool place if you haven't been).

I am assuming that there is an issue with the head gasket and combustion chamber pressure is making its way out to the water jacket and then passing the water to the overflow and out when the pressure/volume gets too high. I plan to take the motor apart in the next few days to confirm/repair.

Any thoughts on whether this is the likely culprit or anyone have experience with this type of failure they can share?

Any tips/tricks for preventing this from happening again in the future?

Is there a known good process that ensures that the head is torqued correctly? The owners manual instruction is:

"Tighten the cylinder head nuts whilst following a cross-over pattern and in steps to 37 Nm+90deg. - 3.8 kgm+90 deg. - 27.5 ft/lbs+90 deg. (+MOLIKOTE HSC)"

Is there a need to go back and retorque the head bolts after a period of operation to alleviate this issue?

Also is there some quick way to determine which thickness head gasket is needed? They are sold in 1.0, 1.1 and 1.2mm thicknesses and I am curious how to determine which is the correct thickness for my motor.

Thanks

Joel

 

[OlderHuskyRider]

I am assuming that there is an issue with the head gasket and combustion chamber pressure is making its way out to the water jacket and then passing the water to the overflow and out when the pressure/volume gets too high. I plan to take the motor apart in the next few days to confirm/repair.

"Tighten the cylinder head nuts whilst following a cross-over pattern and in steps to 37 Nm+90deg. - 3.8 kgm+90 deg. - 27.5 ft/lbs+90 deg. (+MOLIKOTE HSC)"

Is there a need to go back and retorque the head bolts after a period of operation to alleviate this issue?

Also is there some quick way to determine which thickness head gasket is needed? They are sold in 1.0, 1.1 and 1.2mm thicknesses and I am curious how to determine which is the correct thickness for my motor.
Thanks
Joel

You can try replacing the rad cap, use the same pressure that's on it, I have a almost 3 year cap, it's in fine shape....

My HG developed a leak, overheating was my main symptom, also, I was getting leak-back into the combustion chamber, after 10 mins stopped, I would have a water-logged spark plug and hard starting.

I tried tightening my head bolts to maybe seal up the leak, didn't work. I just set my torque wrench for about 30 pounds and every head bolt took a little movement to get there, but no help.

I changed my HG out and have not yet gone back to re-tighten the head bolts, laziness is king in my world.....

The HG on your bike now is marked on a tab in the rear, use the same size, it was chosen at the factory to alleviate/make up for machine tolerances/differences in deck height and make the cam timing as close to the marks as possible. If you use a different thickness HG, you WILL have to adjust your expectations on the cam timing marks, this, I know.

 

[tls25rs]

OlderHuskyRider,

Thanks for the reply! I'm going to take a look at it this weekend and hopefully be able to figure it out.

Joel

 

[nikjoh]

mine pushed out coolant in the overflow when my impeller in the water pump failed.