Radiator cap

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Coyote Jack

Coyote Jack

Member #55, I'm old
FABO Gold Member
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Has anybody got a part number for a 20 pound radiator cap that will fit a stock 26 inch 2 core 340 radiator? This 16 lb is not doing the job.

Jack
 
LOL
you know what I mean
I ran into the same thing on a 11:1 motor, bigger fan helped, bigger rad fixed it.
 
The problem is that it spits out coolant when I turn the car off. It does not overheat while driving. It runs at 185 to 195 depending on the day.

Jack
 
It could even just be a bad cap, as there is no reason for a 16lb cap to do that unless it's getting hotter than that.
(well, unless there is a compression leak in the block somewhere)

IMO, replace the 16lb cap, and if that doesn't do it then a recovery system.
Remember, a higher pressure cap will just put that much more pressure on all your hoses, radiator and heater core.
 
My 67 273 did the same thing if I filled the system to the cap. Somewhat embarrassing to roll in at the cruise-in and dump a pint. One solution is leave the fill level low, barely cover the tubes like the factory prescribed back then. Then it dumps a little air if anything, and the air adds to the rusting and all that is why they added a reservoir. That's why I added a reservoir to my 67 too. I found the translucent plastic reservoir quite beneficial in that I see the cooling system condition at a glance, while pulling oil dipstick, whatever.
 
My 7 pounder has never let me down, but I do have an expansion tank. It came off a 73 Dart. I had to drill a hole for the bottom locator, that's all.
Course it seldom gets over 37*C around here. That'd be 98.6,lol. I've never seen 40(104*F) in Manitoba. I seen it in BC tho, back in 75 when we were crossing the Great Divide; on motorcycles. Liquid Cooled Water Buffaloes they were. Ugly, heavy, ill-handling, not particularly powerful, but they'd probably run in an iron smelter; for a bit at least. Yeah, they didn't care how hot it got or how fast we rode, those temp gauges barely moved. Good memories right there.......When we got to the top, we saw a lot of bikes and cars, waiting for the airtemp to drop.I think the thermometer was showing 104. We had no idea; we had the road to ourselves and we were booking it. And no helmet laws in those days either. Goggles in July are kindof mandatory tho,lol. Some of those bugs I swear weigh over a pound at the speeds we were traveling.Hyup, good memories.
 
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There are 2 different style rad caps. The 1 with out the recovery system has a single rubber in it. The recovery 1 has 2 rubbers. Kim. Oh ya. Ha ha
 
TrailBeast said:
It could even just be a bad cap, as there is no reason for a 16lb cap to do that unless it's getting hotter than that.
(well, unless there is a compression leak in the block somewhere)

IMO, replace the 16lb cap, and if that doesn't do it then a recovery system.
Remember, a higher pressure cap will just put that much more pressure on all your hoses, radiator and heater core.
Click to expand...



I agree 20 pounds is a lot of pressure, especially for most hose clamps.

TB is correct. I have had brand new caps puke like that. I ASSumed that they had a bad run of springs or something. When you shut the engine off, the temp goes up. As much as 50 degrees. The coolant expands and it pushes past the cap, which I'm sure you know. When it can't expand it builds pressure and overcomes the cap.

I'm thinking 20 pounds is asking for a failure somewhere else.
 
Thanks everybody, I'm going to try a new cap first and if that doesn't do the trick then I guess I better find room for a puke tank.

Jack
 
O'Reilly Murray part # 7020.

Damn yall, the dude has a blower on his engine. Might be a little different than the average bear, ya think?
 
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