I was worried that My 4.3 might have been leaking. Did a uoa and absolutley NO coolant or moisture was found. Does this 100% rule out a leaking intake manifold gasket? Still seems like im loosing a very very small ammount of coolant from my tank.
Do I have an intake gasket leak?
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Water Pump is in good shape? Heater core hoses in good shape? Could be one of these has a very small leak?
Jeff
Jeff
Water pump is dry and no hose leaks. That I can see.
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Heater core hoses are tricky. Does this suv have a plastic core radiator or all metal?
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Could also be a faulty radiator cap not holding psi and is venting a little past the seal.
It can leak externally and evaporate w\o getting in the oil.check the radiator for cracks near where the upper hose is.look on the front side.
My cars tend to lose about 1-2 ounces in a 2 year period. I can never find a leak or drip. I guess some does "burn off" over time. So I guess if I added it up by volume/mileage it would be one ounce every 20,000 miles. The wifes car had lost about 4-5 ounces at 100k. I did a uoa..no coolant. Now at 195k still no loss beyond the 1oz /20k
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The intake manifold gasket is one of the least likely potential coolant leaks that there is. That's not to say it isn't leaking, but it should not be the first place that you look. Even with the history GM has had with leaky intakes eliminate the more likely suspects first.
As Jeff said, check the water pump, heater hoses, radiator hoses, radiator. The S10 in my sig had had a very slight seepage at the fittings in the radiator for the ATF lines for a while. I tightened up those fittings and that took care of that.
If the leak is as minute as you described you may not find a drip or wet streak anywhere, but you may find a small, dried trail of coolant.
Check the cooling system when it's hot and pressurized, unless you have access to a cooling system pressure tester. This is the kind of a search that will benefit greatly by having an inspection mirror and a good light for looking underneath and around visual obstructions.
As Jeff said, check the water pump, heater hoses, radiator hoses, radiator. The S10 in my sig had had a very slight seepage at the fittings in the radiator for the ATF lines for a while. I tightened up those fittings and that took care of that.
If the leak is as minute as you described you may not find a drip or wet streak anywhere, but you may find a small, dried trail of coolant.
Check the cooling system when it's hot and pressurized, unless you have access to a cooling system pressure tester. This is the kind of a search that will benefit greatly by having an inspection mirror and a good light for looking underneath and around visual obstructions.
How does the motor run? Any kind of stumble? Loss of power? Rough idle? Stumble on acceleration? Does any white smoke or steam come out of the tail pipe? Have you pulled the spark plugs and found any of them "super clean" (like they've been steam cleaned). Just some thoughts.
Originally Posted By: Chris142
It can leak externally and evaporate w\o getting in the oil.check the radiator for cracks near where the upper hose is.look on the front side.
This is exactly what I found on the "Bluesmobile." Very small crack directly beneath the upper rad hose on the plastic part of the rad. Would only open up under pressure.
It can leak externally and evaporate w\o getting in the oil.check the radiator for cracks near where the upper hose is.look on the front side.
This is exactly what I found on the "Bluesmobile." Very small crack directly beneath the upper rad hose on the plastic part of the rad. Would only open up under pressure.
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