Re: bypass tube on head

Glen,

You did not say if you are using the heater core inline.  It's a must for 
proper circulation thru #4 area!  Even if the air across the heater core goes 
nowhere, it does about 8 degrees of cooling AND stabilizes the rise of that 
"mysterious" heat build up.

I had that problem with the 1275 or the 1380 without the heater in line.  I 
have not found that heat under the bonnet stays or causes a problem.

http://ourworld.cs.com/JCareyPage/JCareyPage.htm

Later, John