Still to warm, The conclusion

[beeze455]

Have you tested or bought a new raditor cap? Have you tested the pressure of the system while it is running?

Drilling holes by the instument panel\vent kit, water wetter, extra cooler, turning the fan on earlier, different thermostat, drilling a hole in the thermostat, engine ice, ice scratchers, running studs, pissing on your engine at every stop are all items that will keep your engine cooler. I would not do many of these and dont think you should bother yet because you have a problem.

I bet your system is not building pressure.

Do you have a pressure tester?

Buy something like http://www.amazon.com/Mityvac-MV4560-Ra ... ure+tester

Hook the unit up and pressure it up and run the engine and see what happens.

 

[1975FA]

only someone who has no idea what a bad head gasket is would think it was... warm exchangers = coolant flow = no air bind. simptom would be oil in coolant and vice versa and quite possibly still not over heat until coolant gets low...

This is what keeps chewing on me, no oil in the coolant, no coolant in the oil, no exaust stinky in the radiator or the over flow tank and on the first start up no ainti freeze smell in the exaust or cylinder miss. This morning when I rode 5 miles to work it was -20 and 5" of powder snow. The light came on just as I got here. The tunel cooler was encased with ice the front one slush packed.

 

[Grimm]

When you put new coolant in, did you flush out the system? I remember seeing a thread recently of someone with a Nytro replacing the radiator and the inlet and outlet pipes were almost plugged up with crud (don't know what else to call it). That would certainly restrict coolant flow. Maybe you have a similar issue throughout the system.

Slush buildup on the front and tunnel heat exchanger also doesn't help, it needs to allow air and snow to pass over them to cool efficiently.

I remember back a few years ago, I had to ride my Nytro with the hood off and slung around my shoulder so it wouldn't overheat while riding on a lake. Very embarrassing riding a new sled this way.

 

[sgilbert]

only someone who has no idea what a bad head gasket is would think it was... warm exchangers = coolant flow = no air bind. simptom would be oil in coolant and vice versa and quite possibly still not over heat until coolant gets low...

This is what keeps chewing on me, no oil in the coolant, no coolant in the oil, no exaust stinky in the radiator or the over flow tank and on the first start up no ainti freeze smell in the exaust or cylinder miss. This morning when I rode 5 miles to work it was -20 and 5" of powder snow. The light came on just as I got here. The tunel cooler was encased with ice the front one slush packed.

OK soooooo, hot engine, cold echangers = coolant is not circulating then, correct? only possibilities. pump not turning. blockage or kinked line. coolant low. stuck thermostat. if it had anything to do with any gasket, it would leak coolant into the oil or external or into combustion, which would also get into the oil. coolant would be low and contaminated. I have never seen a headgasket over heat an engine without being low on coolant. that term gets thrown around from the toyota days.

 

[sgilbert]

only someone who has no idea what a bad head gasket is would think it was... warm exchangers = coolant flow = no air bind. simptom would be oil in coolant and vice versa and quite possibly still not over heat until coolant gets low...

This is what keeps chewing on me, no oil in the coolant, no coolant in the oil, no exaust stinky in the radiator or the over flow tank and on the first start up no ainti freeze smell in the exaust or cylinder miss. This morning when I rode 5 miles to work it was -20 and 5" of powder snow. The light came on just as I got here. The tunel cooler was encased with ice the front one slush packed.

OK soooooo, hot engine, cold echangers = coolant is not circulating then, correct? only possibilities. pump not turning. blockage or kinked line. coolant low. stuck thermostat. if it had anything to do with any gasket, it would leak coolant into the oil or external or into combustion, which would also get into the oil. coolant would be low and contaminated. I have never seen a headgasket over heat an engine without being low on coolant. that term gets thrown around from the toyota days.

 

[1975FA]

I think the tunel exchanger was more of the bridged over ice from the tunel protector on a -20 morning. I have checked both heat exchangers for blockages, the radiator is new, the thermostat is new and checked in hot water, my waterpump is rebuilt including a new impeller, the temp sensor is new also, antifreeze is 50/50 with a wetting agent. One thing was mentioned here that I have skipped over. The system has been presure checked but not the cap. If the cap pops off at a low presure I start loosing coolant to the overflow. When the system get low enough the light comes on. I just ordered a new cap. In the mean time I found an o-ring that fits under the cap. That should increase the system presure, raising the boiling point and retaining coolant.

 

[beeze455]

Did you pressure test it hot though?

I will find the you tube video that explains this.

 

[beeze455]

Go to you tube and type "mityvac mv4560 cooling system test kit" and watch the full vid. Do this and let use know your results.

You can use any tester. Autozone will let you borrow them for free also. If your in Maine, you can borrow mine.

 

[09nytro]

only someone who has no idea what a bad head gasket is would think it was... warm exchangers = coolant flow = no air bind. simptom would be oil in coolant and vice versa and quite possibly still not over heat until coolant gets low...

I work on sled ,ATv's ,watercrafts,motorcycle all day every day so I do know what a blown head gasket is just like skoalringll said there are many ways

 

[Off Trail Mike]

Probably tried this but what about your thermostat? Its a balanced thermostat system with 3 hoses coming from the thermostat housing it so coolant is circulated only thru the block until it warms up and then gradually, the radiator/cooler comes into play.

So if the thermostat is messed up, or partially working, then you will be circulating too much water thru the engine and NOT in the coolers, thus an overheat.

I checked my Nytro service manual and it says IF the thermostat does not start to open at 69-73C (156.2 - 163.4 F) then replace it. It should also be more than 8mm open at 85 deg. C (185 deg F).

This is checked by immersing it in a pot of water with a thermostat and slowly raising the temp.

Worth a try....


OTM

 

[1975FA]

Probably tried this but what about your thermostat? Its a balanced thermostat system with 3 hoses coming from the thermostat housing it so coolant is circulated only thru the block until it warms up and then gradually, the radiator/cooler comes into play.

So if the thermostat is messed up, or partially working, then you will be circulating too much water thru the engine and NOT in the coolers, thus an overheat.

I checked my Nytro service manual and it says IF the thermostat does not start to open at 69-73C (156.2 - 163.4 F) then replace it. It should also be more than 8mm open at 85 deg. C (185 deg F).

This is checked by immersing it in a pot of water with a thermostat and slowly raising the temp.

Worth a try....

Thanks for the input. I checked my new thermostat as you discribed. It was one of the first things I did. I'm waiting for a new radiator cap right now, it's the one thing I kind of slid right over. The presure on these caps is high 15.3psi to 19.5psi. If it starts to dump into the overflow tank at a lower presure I'm going to get low coolant and get warm. At 19psi the boiling point is going to be raised substantially.
OTM

 

[sgilbert]

I would think if the cap were bad, it would take several rides to be low on coolant and the overflow tank would be dumping. hard to believe that they would sell you a radiator and not a cap

 

[beeze455]

Any update?

 

[1975FA]

I ordered a new cap, but found somebody that could check my cap before it arrived. Tested fine, it poped at 17 or 18lbs. Right now the engine is on the bench. The head is being resurfaced while I wait for the gaskets and new head bolts. The head gasket didn't have any pieces missing but there was carbon under the fire ring on the middle cylinder. The head bolts had taken a real set to them. I broke 4 snap-on six point sockets getting them loose. Three bolts rounded just enough that I couldn't get ahold of them, so I drilled the heads off. They screwed right out with my fingers once the head was out of the way. This engine has 5500 miles on it and you can still see the cross hatch marks in the cylinders. I should have everthing ready to go back togeather next week when I get back from a service school for work.

 

[cannondale27]

How do the plugs look?Even a 4 stroke can run hot if too lean on fuel.