Packard Forum Index » Pre-War (1899-1942)

'37 120c. just a coolant change, but was suspicious of the picot of breaking,so removed the radiator hose from the radiator and head. The coolant leaks from both places not under pressure now. I have cleaned the inside of the hose as it had rust stuck to it. I did sand the outside of the lower radiator connection with very worn out sandpaper (didn't want to overdo it). What sandpaper or device do you suggest I use on these connections to clean them? Not easy to get to the lower radiator connection. While the hose looks good (not soft or cracked) maybe a new one would seal better?

Replace the hose clamps with new ones and perhaps move them to a new spot on the hose.

The 37 isn't a pressurized system, so the fact they are leaking from just water pump pressure is very unusual.

Perhaps new hoses are in order.

New hose and clamps is what you need. Old hose with rust embedded may never seal. Old clamps are often troublesome, too. My '37 120 C uses 1 1/2" ID straight hose on the lower hose and steel elbow, and the upper hose was 1 1/2" ID straight hose. I replaced the upper hose with 2 short lengths of straight hose and a piece of 1 1/2" exhaust pipe. That exposes another 22 square inches or so of metal to the air for a little added cooling surface. I'd avoid using flex type hose on these cars, especially on the lower hose.

thanks, new hose and clamps and sanding and a 1/4 drive rachet (had tried 3/8's but couldn't get it on the clamp) worked. No leaks. The temp got up to 180, cooled a bit and returned to 180 but I didn't see the thermostat open. Top of thermostat housing did get hot. At least the block won't crack in the cold winter. Thanks for the support.

Be sure it is full of coolant. It should take about 4.5 gallons, maybe a little more with a heater. I'd run it at least long enough for the air coming through the radiator to get warm. Unlike some vehicles, my '37 120 does not show much of any agitation in the upper radiator tank when the thermostat is open, even at a fast idle.

Just as a tidbit aside, gear clamps are usually designated 'HS', HSS' & 'HAS'. 'HS' have stainless band with galvanized screw and housing; 'HSS' have SS band, SS screw and galvanized housing, while 'HAS' are 'all stainless'. While the designations may vary a bit by manufacturer, the 'all stainless are very much worth the extra cost and don't corrode over time. And, in cases where 2 clamps are involved, always oppose the position of the housings. The tendancy is to line them up to make them look nice and neat but the pressure imposed with a gear clamp is like a teardrop with the point being the housing. Oppsoing them cuts off the leak path. Chris.