Last night I was riding going up a long step hill when I top it started to desend the motor quit look at my overflow and the engine ice was sprying out on my legg but it was not hot enough to burn my legg. when i turned the key over the fan ran for only a couple of minutes and on top of the head it looks like there is gas and oil coming out of one of the head bolts.
this motor just received a top end rebuild with a wiseco piston and the head milled .015 m going to tear it down tomorrow what should I check for.and should I be using some kind of sealer around the head studs?check the plug also and it was brown so it wasn't lean

 

be sure to torque spec the head bolt after a run when you got a rebuild,
it just look an un-sealed coolant system problem to me,bleed the coolant
system properly,you can even put loctite or high performance silicone on them before screw them in.

 

what is the proper way to bleed the head and since I got it pretty quick do you think it did any damage!!
what adapter do you use for the torque wrench to do base nuts and were can I get one


thanks
Scott

 

Like Scramblered stated, it's pretty important to re-torque those base bolts. Many of us who have been through the top-ends on a regular basis (not due to failures, just freshening every once in a while due to 15.5:1 race mods)don't use a torque wrench on the base bolts, we use the "calibrated" method of estimating. If you want, you can use the torque wrench on the couple of bolts which are easy to get to, then estimate on the others.

There is a air bleed screw on the RH (viewed as your sitting on it)side of the head. By the temp sender. Also, Redline's Water Wetter helps cooling a bit more, and also seems to have greater lubricity.

 

Id also check the 6 studs in the top of the jug. You may have a couple loose. if they werent loose then, they may be now. (since it got hot) I dont think I like the gasket stuff some people use, the gasket allready has some kinda sealer on it. Also wont hurt to drop the head off at a machine shop to check to see if its warped. My cousin ran his hot this winter, and it took 3 tries till we finally gotit rite.

 

Do the 2 strokes have thewrmostats?? Sounds like the stat failed closed so no water was getting through to the cooler.

Chris

 

csamayfield55

how do you like the exhaust on your 500 HO. can u tell any difference on power i was looking at one also. did u rejet it

 

what procedure do you use to bleed the head .....crack the bleeder while it is running until fluid comes out????[img]i/expressions/face-icon-small-confused.gif[/img]

 

The 2- stroke 400 engine doesn't have a thermostat. You can back off the bleeder screw, then pour in coolant. You'll eventually see some coolant leak out.

As for adding additional sealer....like Whitedog stated, there's already a bead of silicon on the gasket. It's just very important to re-torque once the machine has been thoroughly warmed. Considering we triple the horsepower from these motors (reliably), they're a very durable design. [img]i/expressions/face-icon-small-smile.gif[/img]

 

wouldnt b a bad idea to invest in a water temp guage. i got one and i love it. like white dog said, check head for warps. i took my head off and had it shaved when mine overheated, but i still had a antifreeze leaking. turned out to be the top of my jug was warped. for 25$ you can have it milled. id defintly have my jug checked out too.

ross