Radiators and Cooling In Old Kenworths

Rad. tech has changed over the years. They don’t have to be as thick as they used to be anymore.
Had my original rad in my Pete 351 recored back in ‘09. This is a butterfly hood so the rad is external and the polished nose of the truck, so just buying one in a box isn’t an option. The original core was 6” thick pure copper and weighed close to 100lbs. The new custom made core is 3” thick aluminum and half the weight.
NTC 350 sc after cooled (known to get hot fast in a hard pull back in the day). With grille shutters open and no fan on It will run 120 degrees in summer just tooling around with no load.

 

We had a W924 here with a Small Cam 335 that was rebuilt as a 380. If you had any fuel on it at all below 1700rpm it went volcanic almost instantly. Moving the crusher with it you had to roar it 1900-2000 to keep it from melting. Good truck though, as long as the engine ran you could fix anything else with a ball-pein hammer and a pair of vise grips.

 

Water pump design. The cpl 160 350 sc’s were the first for the “suitcase” style. Uncle ordered this truck with the 335 which was big power in ‘67. Standard engine in a Pete at the time was the 250. He ran south Tejas up thru the Montana Rockies for 30 years and 3 overhauls. When it was time for it’s fourth in ‘92 he pulled the 335 and put in this 350 out of one of his ‘74’s. He always said the 350 lowered his stress level because the temp control was so much better.

 

At least with the cabovers the air can pass right through the rad and straight out the back of the cab

Seems that would help , verses a conventional where the hot air has to get pushed down under the cab to escape

 

All that heat vents right up thru the hole in the floor for the shifter tower. If not sealed good you can feel the extra rush of air every time the fan kicks on.

 

I had two Freightliners with 3408’s in them. One was a Powerliner and the last one had an American cab with the small grille opening. Needless to say one cooled itself a lot better than the other.

 

I think it was the pump made the cooler efficient enough to actually work. There didn’t seem to be a hell of a lot of difference between uncooled and cooled engines before they changed the water pump.

 

Those old round water pumps with the copper o-ring seal never allowed you to get the belt tight enough and if you did it wouldn't stay tight long. Have to have a “special” tool or mickey mouse screwdriver to rotate it for belt tension.