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Mod | | | Forums66 Topics128,172 Posts1,057,109 Members48,463 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Mar 2010 Posts: 46 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2010 Posts: 46 | My 1941 Chevy 1 1/2 Ton (4408) has a round dimple at the very top of the radiator with an hose fitting (Hose is routed down to the bottom of the radiator on the driver side. Last time I drove it started pouring wawa at about a quart a minute when it reached 180 degrees. No over flow on the filler cap neck.
While I'm at it. what temp is the thermostat supposed to open at and what is the proper pressure cap for the radiator?
-=JD=- | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | zero pressure cap back then, and yes, the hose is an overflow which won't overflow at normal operating temps if you don't overfill the rad - should be down a couple inches when warm, nearly down to the top of the fins when cold .... a 160 thermostat should work fine, a 180 if you use it regular in winter and have a heater - stats should be fully open at about the temp rating, you can check it in a pan of water on the stove with a kitchen thermometer
Bill | | | | | Joined: Mar 2010 Posts: 46 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2010 Posts: 46 | Uh Oh! BarsLeak "fixed" the problem. I'm going to pull the hose off and see if I can unfix it. Thank for your help Sir. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | You can also close up the tube or solder the top closed or some variation of the above, solder on a new neck and cap(5 PSI max)w/ proper overflow res. to take advantage of a few more degrees of heat capability.
As it is now, as stated above, it will overflow every time 'til the water level gets static from expansion only.
It is good to use a 185 or 195 Tstat to get the engine warm to burn off water from the combustion process and the engine is more efficient there, especially for short trip use.
Bars Leak, etc., tend to mask other problems(sticking heater valves, if present, other gasket problems) that should really be fixed properly, especially if going on trips away from home.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
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