69 427 cooling-pressure
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Burning Brakes
Joined: Sep 2008
Posts: 753
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69 427 cooling-pressure
is pretty hot here in these days...
half an hour "spirited " ride yesterday and engine temp was Ok ( 185F at cruise, 195F in the town at slow speed) but I found the coolant hose to be hard and pressurized and a little coolant flow out of the coolant reservoir tank.
I have new Alu heads , dewitts Aluminum rad , fan shroud , 180F thermostat, 50/50 aluminum type coolant and distilled water
should I increase the coolant % to raise the boiling point further to avoid pressurization?
half an hour "spirited " ride yesterday and engine temp was Ok ( 185F at cruise, 195F in the town at slow speed) but I found the coolant hose to be hard and pressurized and a little coolant flow out of the coolant reservoir tank.
I have new Alu heads , dewitts Aluminum rad , fan shroud , 180F thermostat, 50/50 aluminum type coolant and distilled water
should I increase the coolant % to raise the boiling point further to avoid pressurization?
Last edited by elle88; May 13, 2009 at 01:06 AM.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
There will not be much "flow" from the tank- once the radiator is full and the system is hot most of the coolant will circulate thru the radaitor and engine. Not all, but most. YOur radiator cap will take care of the pressure, so the hose being hard is not an issue. If you're running much over a 50/50 mix of coolant and water you're wasting $$.
That pressure you're feeling is actually raising the boiling point of your coolant.
That pressure you're feeling is actually raising the boiling point of your coolant.
Le Mans Master
Joined: Jan 2006
Posts: 6,506
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From: Butler Pa
You can't avoid pressurization. It's very necessary to avoid boil overs.
My '69 doesn't have a coolant overflow/recovery tank so I'm assuming yours doesn't either. If the system is completely full when cold, it will spew some coolant out when it heats up. The fluid level will stabilize after several heat cycles.
My '69 doesn't have a coolant overflow/recovery tank so I'm assuming yours doesn't either. If the system is completely full when cold, it will spew some coolant out when it heats up. The fluid level will stabilize after several heat cycles.
Race Director
Joined: Jul 2001
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Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
That's correct, but no Corvette prior to 1973 had a coolant overflow/recovery tank.
Le Mans Master
Joined: Nov 2008
Posts: 5,691
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From: columbus oh
i installed a small block surge tank on my 66 big block and adapted it for a recovery system by using a vented cap at the rad and a sealed cap at the surge tank..works quite well and will run 180-185 with no pressure on any hoses...after 190 especially in parades it will build pressure as the vented cap closes ......
.....this way there is absolutely no coolant loss as it is captured and returned to the rad as the mill cools or after a long shut down.......
.....this way there is absolutely no coolant loss as it is captured and returned to the rad as the mill cools or after a long shut down.......
