Over heating
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
There has been a few threads on the flex fans mostly negitive as they don't seem to move enough air. Hard to beat the stock steel fan with the thermo clutch unless you switch to the electric type.
Not sure about 77', but my 78' only had one hose from the rad. The AIM shows a second hose from the cap which pees out on the ground if the bottle gets full. I'm thinking that hose was eliminated by Uncle Sam as that would polute the ground which is what the "Coolant Recovery Tank" was suppose to stop.
Gary
Not sure about 77', but my 78' only had one hose from the rad. The AIM shows a second hose from the cap which pees out on the ground if the bottle gets full. I'm thinking that hose was eliminated by Uncle Sam as that would polute the ground which is what the "Coolant Recovery Tank" was suppose to stop.
Gary
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
slow speed over heat is usually a sign of low air flow, fan clutch or in your case likely a cheesy fan. The 77 has 1 hose from the rad to the overflow jug, it goes to the line that runs thru the cap to the bottom of the jug, the other line on the over flow jug cap vents out on the ground.
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
If your distributor has a vacuum advance mechanism, check that the rubber hose is hooked to manifold vacuum and not ported vacuum ( carb fitting ).
More ignition advance at idle / low speed should improve cooling :
Exhaust gases are still burning after the valve with only 6-10° initial timing, so those gases heat the cylinder head walls.
If you add 12-15° vacuum advance, the mixture will burn almost completely inside the cylinders.
The engine will also produce more power that way, so you'll need less fuel at idle / cruise speed. That means economy AND less produced heat.
This can also improve a choppy idle caused by a big cam.
Last edited by 73StreetRace; Jun 29, 2010 at 11:41 AM.
