Losing Coolant. Any ideas?

[GrandmaLS]

Every 500-750miles I pop the hood and put between 1/4-1/2 gallon of coolant in the '94. There is none in the oil and there is NO white smoke coming out the exhaust. Only a puff or two of black when I start the car every now and then. I know that's oil though. No puddles on the ground either.

Maybe it only leaks when the car heats up when driving?

Suggestions on things to check would be great!

Vehicle:
1994 Chevy Camaro 3.4

The car had a new water pump put on last summer. I checked anways and can't see anything coming out the weep hole.

Tom

 

[ReiKo]

What kind of car?

 

[GrandmaLS]

Sorry! 1994 Chevy Camaro 3.4

 

[Instigator]

leaky intake gaskets will do that if its a small enough leak it will go though coolant and not smoke hope this helps, it happen to my wife in a Alero (sp?)
you can put pressure to the rad (motor off) and wait to see if it looses pressure to give you a idea if thats the problem

 

[dirtybird]

Hoses, coolant jug leak :dontknow:

 

[Sean]

I would bet on lower intake gaskets. They are a huge problem on most all GM vehicles. Look at the corner where the head meets the manifold in front and back of the motor.

 

[1BADAIR]

intake and or head gaskets.
very common

 

[GrandmaLS]

Hoses, coolant jug leak :dontknow:

Hoses.....no
Coolant jug......would maybe matter for a few ounces because I never fill it

leaky intake gaskets will do that if its a small enough leak it will go though coolant and not smoke hope this helps, it happen to my wife in a Alero (sp?)
you can put pressure to the rad (motor off) and wait to see if it looses pressure to give you a idea if thats the problem

I would bet on lower intake gaskets. They are a huge problem on most all GM vehicles. Look at the corner where the head meets the manifold in front and back of the motor.

intake and or head gaskets.
very common

We did intake/head gaskets late last fall. I'd hope wouldn't go out this fast

I can't SEE any dirt collecting around the heads/intake. Normally when they leak you get a bit of dirt built up. The only leak I can see is the drivers valve cover and that's just sputtering out a bit of oil on to the head.

I also checked the heater core but you can't see/smell anything.

 

[beertestr]

I know you said you didn't see anything in the weep hole of the pump, but it might be leaking slightly and evaporating. Coolant is mostly water and alchohol, so it might be losing there and it evaproates off before you notice it.

Do you ever smell coolant?

Sean is right, the 2.8/3.1/3.4 intakes are prone to leaking, what with the 5-plane sealing surface (valley seal, and 2 planes on each head, compared to an SBC's 3 or and LSx's 2.

Another thought is that the intake gasket is leaking into the engine, and the PCV is evaporating it off too. You'd likely see a bit of that in the exhaust though. Pull a rocker cover off and check for white residue. If you have it, it's a sure sign of Dexcool the oil.