Cat 3406B getting hot!!

The fan isn't supposed to kick on until 205* and the warning shouldn't come on until 220 or 225 IIRC. The first new radiator I put in my truck was a 5 row staggered and it cooled the best, the second one is just the 5 row and its not as good as the first one, but it does the job. I also run of 100k gross every day.

Another thing to check is make sure the gauge is working correctly. You can also change the sensor for the when the fan comes on.

 

Les where did you purchase that 5 row staggers from? Was it a copper core?

 

somebody didnt put bars leak in at one time did they? or green antifreeze.

 

I think it was Detroit radiator and yeah it was copper.

 

Top tank & the radiator core are separate. The only thing connecting the tank to the core is a vent line or an iternal vent. If you had lines capped off & isolated the tank it will hold water & not drain into the core. not sure what you meant when you said you pulled the lower hose & blocked off the rest.

 

bells went off in my head when i read this post. he is right the best way is to take off the bottom tube and with a light look up in the radiator, you can see some off the tubes to see if they are pluged. personally i like red antifreeze over green you dont get the cavitation like you do with red.

 

it drains but slowly. it's just a surge tank thats mounted on the top of rad. some of your newer petes have them on the firewall with a small line going to the rad.