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| | | | Joined: Apr 2006 Posts: 31 Apprentice | | Apprentice Joined: Apr 2006 Posts: 31 | Hey guys-
In my 53 3100 I'll be running a '56 235 with proper after-market short-shaft 235 water pump, the big 5-blade (car) fan, and the original radiator. The radiator has no leaks and has never been repaired, and I would really like to keep it that way. Given that I am not planning on overworking the truck and have the right pump and big fan, I am tempted to order the zero-pound radiator cap, but I know running with pressure lowers the boiling point and makes the system more effective. Seems the 4lb, or 6-7lb might be closer to what this '56 235 used originally. Do you think it matters in terms of radiator longevity? Also, I do plan on drilling the hole in the thermostat, and wondering if running a 160 degree thermostat might be better if I did go with the zero-pound cap. Any opinions? | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | I would use a 4 lb. cap & 180 therm. If a radiator can't stand 4lb. it's time for a repair or replacement.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | what wrench sez - the 56 would have had a 7#, but the earlier trucks used 4# and your rad should take it - also, running the engine warmer is better than too cool, go 180, shouldn't be a problem
Bill | | | | | Joined: Feb 2004 Posts: 29,796 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,796 | Each 1 lb. of pressure raises the boiling point by 3 degrees F., so a 4 lb. cap will add 12 degrees to the boiling point- - - -224 degrees at sea level. If the radiator is clean, and you've got an efficient fan, that gives you 44 degrees of leeway between thermostat opening and boil-over with a 180 degree stat. Unless you're operating on an extremely hot day, or working the engine hard, that should be plenty of operating range. The 7-lb. cap would add 21 degrees to the boiling point, but it might be a bit hard on the radiator.
Jerry
Last edited by Hotrod Lincoln; 08/30/2009 8:22 PM.
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| | | | | Joined: Apr 2006 Posts: 31 Apprentice | | Apprentice Joined: Apr 2006 Posts: 31 | Thanks guys for the help. Sounds like 4# and 180F is the way to go. Thanks again, -W | | |
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