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| | | | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | I have an 848 head on my 261 (yep, the holes have been drilled). It has the two-piece thermostat housing with each piece having the extra threaded holes. How are those holes used?
Do you connect them with fittings and short length of hose?
Thanks!
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.
| | | | | Joined: Feb 2001 Posts: 1,897 Member | | Member Joined: Feb 2001 Posts: 1,897 | Run an extra heater for the drivers feet  I believe you should be able to find pipe plug fittings to block them off.
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#7076 10/26/2003 12:01 AM | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Yep. Brass or cast pipe plugs work fine.
If you do not need the hot water for a foot warmer, use the extra outlets to heat an Offenhauser intake.
Tim | | |
#7077 10/26/2003 12:03 AM | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | Luke, To heck with the feet. I'll run a coil of hose in the driver's seat!
What are those holes for? If you connect them, you defeat the purpose of the thermostat.
I will drill a 1/8 in. (or slightly less) hole in the thermostat plate to eliminate any steam or air build-up.
Tim, Your post beat my reply. Intake warmup seems like a great idea. I just put in a frost-plug heater. It's only 500 W but it's below the manifold and puts the heat right where it should be. After 5 hours of heat at 20 below, the old 235 would start right up. I'll also use a 250 W magnet heater stuck to the oil pan when it gets really cold. I have a nifty 2x2 set-up to put it on and take it off without having to crawl under the truck.
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.
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Wally,
My 261 that came from a school bus had them, and as Mechainiac said, they were hooked up to a second heater (in the back of the bus).
Tim | | | | | Joined: Oct 2001 Posts: 3,458 Extreme Gabster | | Extreme Gabster Joined: Oct 2001 Posts: 3,458 | One of those sets is supposed to go back to the water pump, whether it is by way of a heater core or just a hose. The whole purpose of the bypass thermostat setup is to allow water to circulate through the engine and head without hitting the radiator to keep the whole block a uniform temperature.
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#7080 10/27/2003 12:50 AM | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | I think I'm getting it!
I should hook the heater core to the lower of the two holes on the thermostat housing, right? That's the hole below a closed thermostat. The hole above the thermostat will only get flow after the stat opens.
Does it matter which of the two holes on the water pump is hooked to the heater core? Looks like a toss-up there.
Thanks, again.
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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