Nytro coolant loss

[Nick454]

Calling all Yamaha gurus, I have a 12 nytro with an mpi blower. The problem I'm having is coolant loss. Pressure tested the coolant system to 20 psi for 24hrs no loss. Ive done a cylinder leak down test with no issues found. Oil is clean ,no leaks , and no smoke. Any input would be greatly appreciated!

 

[74Nitro]

Calling all Yamaha gurus, I have a 12 nytro with an mpi blower. The problem I'm having is coolant loss. Pressure tested the coolant system to 20 psi for 24hrs no loss. Ive done a cylinder leak down test with no issues found. Oil is clean ,no leaks , and no smoke. Any input would be greatly appreciated!

Most likely head gasket. You're just not building enough pressure with the those tests.
Put the coolant over flow hose into a catch can the next time you ride it.

 

[Srxspec]

Put your coolant pressure tester on the system at 20 psi. Put your leak down cylinder on each cylinder, but make sure it is pressurizing with 100 psi minimum into cylinder, if it is a head gasket it will likely make the coolant system pressure go up if you use the leak down tester to pressurize the cylinders at the same time as the coolant pressure tester is on as well.

 

[BADSLED]

Calling all Yamaha gurus, I have a 12 nytro with an mpi blower. The problem I'm having is coolant loss. Pressure tested the coolant system to 20 psi for 24hrs no loss. Ive done a cylinder leak down test with no issues found. Oil is clean ,no leaks , and no smoke. Any input would be greatly appreciated!

Are you loosing coolant in overflow can only or the entire cooling system?

 

[Mooseman]

If it's puking out the overflow tank, It's likely the head gasket. Had the same problem on my GT. It was fine if driven easy but as soon as I went WOT, the pressure would make the coolant puke out. Didn't burn it or go into the oil neither.

 

[BADSLED]

If it's puking out the overflow tank, It's likely the head gasket. Had the same problem on my GT. It was fine if driven easy but as soon as I went WOT, the pressure would make the coolant puke out. Didn't burn it or go into the oil neither.

 

[Nick454]

Are you loosing coolant in overflow can only or the entire cooling system?

I fill the radiator and the overflow, after about 75 miles the overflow is empty and the radiator is going down.

 

[Nick454]

If it's puking out the overflow tank, It's likely the head gasket. Had the same problem on my GT. It was fine if driven easy but as soon as I went WOT, the pressure would make the coolant puke out. Didn't burn it or go into the oil neither.

Not puking out of the overflow , it's emptying it.

 

[Mooseman]

Any milkshake in the oil or the exhaust smell like coolant?

 

[Nick454]

Any milkshake in the oil or the exhaust smell like coolant?

Nope, I've rode the sled twice, the first trip it started overheating about half way through the day. Hauled it back to camp to fined it low on coolant. The second trip brought coolant with me and had to fill the overflow after 75 miles

 

[Mooseman]

Put the hose that comes out of the overflow into another bottle to see if it comes out that way. If it does, it's the head gasket. Try when running it easy and check. Try again running it hard and check. Mine only puked coolant when run hard.

Is it overheating as a result of the low coolant or something else? How's the thermostat?

 

[Nick454]

Put the hose that comes out of the overflow into another bottle to see if it comes out that way. If it does, it's the head gasket. Try when running it easy and check. Try again running it hard and check. Mine only puked coolant when run hard.

Is it overheating as a result of the low coolant or something else? How's the thermostat?

Low coolant, if I keep it full it's fine, no overheating problems.

 

[Mooseman]

Have you tested the thermostat in boiling water?

 

[Nick454]

Have you tested the thermostat in boiling water?

No, if I keep the coolant full no issues. The only reason it overheated because coolant went low. The temp light was going on and off so it wasn't getting to hot .

 

[Mooseman]

Put the hose that comes out of the overflow into another bottle to see if it comes out that way. If it does, it's the head gasket. Try when running it easy and check. Try again running it hard and check. Mine only puked coolant when run hard.

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