Coolant leak
Thread Starter
Navigator
Joined: Oct 2012
Posts: 9
Likes: 0
Coolant leak
Hi
I found a little coolant sitting on top of the engine beside the thermostat housing the coolant is pure green no contamination only happens now and then,,I can't see where it could be coming from any help would be great 79 vette
Terry
I found a little coolant sitting on top of the engine beside the thermostat housing the coolant is pure green no contamination only happens now and then,,I can't see where it could be coming from any help would be great 79 vette
Terry
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
Before you do anything else take a very close look at the underside of your heater hose running into the intake...the leak you describe is very common and that's usually the cause. There's usually a pin hole there that only leaks when the system is pressurized, so no leak when sitting and not running. If it is that, easiest fix ever, get a new hose and the peasants rejoice. If you can't find a pin hole look at the clamp area and roll the hose around a little in your hand.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Remove the excess coolant and wash/wipe down all of the items in that area. Once they are clean and dry, start the car and allow it to warm up while you watch that area very carefully. You should have a bright light so that you can see well, even in shadowed areas.
Eventually, you should be able to see the onset of that leakage. That will tell you exactly where the leak is coming from, thus the "cause". Once you know the cause, the solution will be simple.
Common causes of leakage in that area: failing heater hose; failing radiator hose; stat gasket leak; minor leak up through the bolt threads of a stat housing bolt (the ends of these bolts should be wiped with Permatex gasket sealant before being installed); porosity in the intake manifold or stat housing castings.
Eventually, you should be able to see the onset of that leakage. That will tell you exactly where the leak is coming from, thus the "cause". Once you know the cause, the solution will be simple.
Common causes of leakage in that area: failing heater hose; failing radiator hose; stat gasket leak; minor leak up through the bolt threads of a stat housing bolt (the ends of these bolts should be wiped with Permatex gasket sealant before being installed); porosity in the intake manifold or stat housing castings.
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
Replacing the Master Cylinder isn't difficult. Two bolts and two brake lines to disconnect and it's off. Use a good set of flare nut wrenches on the lines so you don't round off the fittings and make sure you bench bleed the new Master Cylinder BEFORE you install it. Bleed the brakes (that's the hardest part) and you're done.
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