250 hotter on one side, why?

[BKlingel418]

My 250 pro xb (3 liter) is hotter on the right cylinder bank than the left by about 20-30 degrees. Left side is about 112-120. Right side is 130-140. I took these temps on the hose using a laser temp gun. I had the poppit replaced, and it has brand new thermostats. I even switched the thermostats and get the same result.

Thought it it might be leaky/blown head seals. It's not. Now the hot side has brand new head seals and bolts.

my mechanic advised there was exhaust coming out of the poppit valve hole when he ran it without the poppit valve in. So he thinks exhaust is getting into the cooling system on that side of the motor. Said try replacing the powerhead base gasket and maybe exhaust plate gasket. Any other ideas??

[Fishwhisper]

Seems like I read that it is normal for one side to be hotter than the other side, due to the way water flows through the cooling passages.

[Sparkieboat]

at what temp does your thermostats open? I think it is 130 degrees.

[BKlingel418]

Got brand new 130 degree thermostats in. I'm replacing the base gasket tonight.

[Sparkieboat]

doesnt the water go into the exhaust at some point anyway?