250 XB cylinder head temperature variance?

[Rick H]

03 250XB 0T652470

Is there or what is the cylinder head temperature variance? My starboard is about 13 degrees hotter than the port taken just behind the thermostat in the center on each head running in a 90 gallon tank.

Is this typical?

[fishing122]

It's gonna be warmer because it's higher that's normal.

[Rick H]

It's gonna be warmer because it's higher that's normal.

I assume your saying it's a little further from the water pump is why?

[Gamblinman]

Taking your temp from that location is notoriously erroneous. To get an accurate read, you need to drill and tap the head for insertion of the sender.

[Rick H]

Taking your temp from that location is notoriously erroneous. To get an accurate read, you need to drill and tap the head for insertion of the sender.

Been there done that!

[dkennimer]

Rick, mine is the same way. I ordered a new poppet kit from Don, but haven't replaced it yet to see if it helps... When I do, I'll PM you.

[Rick H]

Rick, mine is the same way. I ordered a new poppet kit from Don, but haven't replaced it yet to see if it helps... When I do, I'll PM you.

Yes, Please do let me know. I have checked the poppet valve when I replaced the t-stats for maint.

My temperatures are well within normal range. Just the port bank is about 13 degrees cooler than the starboard bank. But that's in a 90 gallon tank. It's been a busy spring and long winter took forever to warm up here and now I'm busy doing everything else too. So hoping to get out this coming week and see where they run at more normal conditions.
One more thing water pressure is also within spec but if I raise the idle up to 2000 rpm's for about a minute it does even out to only about 5 degree difference. After about 15 minutes returns to 13 degree difference.

The thermostats were replaced last year I may play with the old ones if running on the lake results are the same as the tank.