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#20519 09/19/2003 4:08 AM | Joined: Dec 2002 Posts: 29 Member | | Member Joined: Dec 2002 Posts: 29 | When I purchased my 1948 2-ton, it came with a 16psi cap on it, which concerned me. I drove it around fine until I could get the correct 0psi cap for it. Then it boiled over all the time, so I put the 16psi cap back on. What is the correct cap to use? I have the stock radiator, but I have a '54 235. Like I said, no problems yet, but it's pretty flat here, with almost no hill climbs.
'48 Chevy 2 ton Flatbed
(daily driver)
'70 BMW 2002
My truck is older than my parents!
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#20520 09/19/2003 4:21 AM | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | I think the 1954 235 truck engine had a 4 lb cap and the car had a 7 lb cap.
Tim | | |
#20521 09/19/2003 4:41 AM | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | Yep, I ran 4 psi cap on a '54 (or so) 235 in my '48 for 10 years with no problems. You might not have hills but it must get pretty hot there in the summer.
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
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#20522 09/19/2003 5:16 AM | Joined: Dec 2002 Posts: 29 Member | | Member Joined: Dec 2002 Posts: 29 | Drove it around fine when it was 109 here, but not for long distances. I'll try the 4psi cap. My stock radiator should be able to handle some pressure right?
'48 Chevy 2 ton Flatbed
(daily driver)
'70 BMW 2002
My truck is older than my parents!
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#20523 09/19/2003 4:33 PM | Joined: Jun 2000 Posts: 2,773 'Bolter | | 'Bolter Joined: Jun 2000 Posts: 2,773 | If the radiator and heater core held together with a 16# cap, a 4# shouldn't be any problem. Those are the parts affected. 4# cap was introduce on trucks in 52.
Things to do to lower the temp include:
1. Getting the radiator boiled to clean out the junk.
2. Back flushing the block. Also be sure that water will flow out the drain cock on the block, if not, clean out the watter passage with some wire.
3. Major tune-up that includes adjusting the valves and checking the timing, both can raise the engine temp if they're off.
Fred
52 3600
69 C-10
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#20524 09/19/2003 5:32 PM | Joined: Oct 2001 Posts: 3,458 Extreme Gabster | | Extreme Gabster Joined: Oct 2001 Posts: 3,458 | I run a 7 lb cap on my 261, but I have a brand new radiator and water pump. I tried the 0 lb cap and it didn't boil over but it did run hotter.
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A lone amateur built the Ark. A large group of professionals built the Titanic. | | |
#20525 09/19/2003 6:34 PM | Joined: Dec 2001 Posts: 1,745 Member | | Member Joined: Dec 2001 Posts: 1,745 | Also, the radiator doesn't like to be full. it will boil over until it reaches a point it likes. Generally a few inches from the top. '54 is 4psi.
54 3100 with 235
62 flatbed dump C60 with 261
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