Info needed: C60 radiator overflow tank connection

[Ken Thomas]

Hi Grant thanks for that. Exactly what I needed. I will take it to the radiator shop tomorrow. Ken. And thanks again to Phil.

[Phil Waterman]

Hi Ken

This is why I have enjoyed MLU for all these years, a question gets asked and answered in short order. Grant beat me on the photos of the Pat 13 Radiator recovery and seam relief tube locations, so below is the top tank of Pattern 12 Chev Radiator which is different.

Pat 12 Rad.jpg

Please post some photos of your new radiator.

Cheers Phil

[Harry Moon]

Do we need the steam relief with a 54 235? High water passeges on the head.

[Phil Waterman]

Hi Harry

I've added them to both my C60S with 261 and C60L with 235. With my testing on engine test stand I've come to the conclusion that running the engine with the steam valve just barely open helps getting the engine to equalize temperature faster and better. My Pattern 12 had overheating problems with 216, before it got the 235 which fixed the over heating. The combination good seal on the radiator cap and coolant recovery tank keeps the radiator full of coolant to the point that when you remove the radiator cap it dumps coolant all over the engine. Loose about 16 ounces of coolant.

Have photos of fittings to use on the latter engine's, will dig them out and post.

Cheers Phil

[Harry Moon]

originally I had the steam line on my 235, later i removed it to relocate the temperature gauge. it then would go way up in teperature and then the thermostat would open and a lot of pressure was let into the top of the radiator sometimes pushing the capo off and overflowing the overflow bottle. i fixed that by drilling a 1/8" hole in the thermostat, no spike in temperature and no boil over. it just rises to operating temperature and stays there.

[Bob Carriere]

Having had the benefit of Phil's experience with the steam tube when I fired up my engine, I decided to install one on my rebuilt 261 WITH the addition of a 1/4 turn valve and a translucent plastic tube from the engine to the rad filler neck.

I ran the engine in various modes of valve open / valve closed and this is what I observed.

After running the engine to full temperature with the valve closed.... when the valve was open a whole bunch of foamy green antifreeze was ejected in the clear tube on the way to the radiator until it was solid flowing green.

When we started the engine with the valve open there was a solid color flow of antifreeze and never any air bubbles. I concluded that the steam vent did serve a purpose and decided to install the permanent steam line with the system left open with out the valve...... on top of the vent fitting on the engine head is the heat gauge sensor which settles in at 160/165 with my 160 thermostat...... never has it over heated.

I see no detrimental effect of having it open and certainly allows the air to bleed out of the head.

My early cab 11 did not have a overflow tank, they were later retrofitted on cab 11, mine never got one. So my side sheet metal panels had no bolt holes ( as found on the cab 12) so I ran my engine with a plastic pop bottle to catch the overflow for quite a while. Satisfied that it was advantageous to have such a tank, I bought and installed an after market Stainless Steel tank for hot rods... it is slim, 12 inches tall and mounted near the radiator horse collar frame under the hood and totally out of view. .... of course it was sandblasted and painted OD green..... and it serves its purpose well.

My permanent steam line and supporting bracket were fabricated from steel brake line covered with the woven canvass/tarred tubing by copying a cab 12 installation.

Cheers