Thermostat bypass questions

[the gman]

I am in the process of installing the ktm thermostat on my fi kx 450 . I was told to just plug the bypass outlet but have some concerns about doing that. 1. When the thermostat is closed there is just a small about of coolant that will slip past the thermostat,will the water pump impeller build pressure causing seal failure, and cause cavitation leading to air bubbles...hot spots in head?? 2. Installing the thermostat 6 inches away from motor ,at the y in my coolant lines,with no bypass will the thermostat sense actual engine heat before engine get too hot. Have seen thermostats both in line, with and without bypass. Plugging bypass is simpler with less places for leaks, but if it works fine 9 out of 10 times....I am usually the 10th. Who has ran these and what works

 

[Mtn. Muncher]

I am running all our KX’s with no by pass. The thermostat valve has 2 bends on the valve and will let enough coolant pass to not over heat year engine. If you do run it with the bypass it will not let the engine get up to thermostat temps.<O</O<O</O

 

[the gman]

Thank you....anyone else

 

[CATSLEDMAN1]

thermo practice

I'm running a yamaha raptor theremostat on my wr snobike, between head and left radiator. I have about an 1/8" hole drilled in flat edge of thermostat to bypass some water and let air through, all good so far. I read the post on using a hose bypass, thought I would give what works on the sleds a go, all the ACats I've owned I made sure it had a drilled bypass. Yam raptor thermostat came that way, I just enlarged their hole a little.

 

[J&L Snowhawk]

Jmo

I just put in a Kawasaki zx6 r thermostat rad cap combo on area51. About 4 inches from engine. No bypas hose. Ran for a bit and seems good in shop.

Ordered a raptor one for buddies kx450

 

[powdermuncher]

The bypass hole allows the engine - temp coolant to go to the thermostat and actuate it once it reaches operating temp.

You need the bypass right at thermostat so it can sense coolant temperature anything going around it makes the system less sensitive.

 

[KAWGRN]

I agree ,,the KTM and the BERG stat housing have the bypass under the tsat, the problem As I see it,,is in the non bypass,, the pump deadheads and squezes water through the hole in the stat real slow so cold water has no choice but to go to the motor slowly, if we are having a problem keeping heat in the motor,, I want the pump still flowing water around the cylinder head and not sending any thing to the radiator and when it does need cooling it blends with the radiator return water so as not to shock the engine, but this is just my theory?

 

[powdermuncher]

If you do that you will have (- 10 degree or what ever it is) water hit your scorching hot engine. "that will not really help engine live"

You need some flow to even things out a bit and get the thermostat to actually sense engine temperature.

 

[KAWGRN]

With the amount of water in the engine and bypass loop its on bypass only for about a minute ,it sends hot water to the radiator and blends bypass and radiator water at the inlet of the pump,so on the berg there is always blended water at the pump inlet,except on start up,I have my temp senser in the return line and its always in the 165 - 190 range.