87 Trans Am 305 with a 4bbl

i have to add coolant about every 3 to 4 days and i dont know where it is going belive me i am a mechaninc i have checked the oil its not coming out the exhaust the over flow is hooked up my heater core is not leaking there are no puddles if i park it and let her run it seems to be just disapearing and i dont know where it is going if any one has had this same problem please let me know cause im at a loss

 

head gasket, its being burnt by the engine, must be a small leak, if you dont notice any white steam coming out the tail pipes. I suppose it could be getting into the intake somehow, and being only sucked out when the engine is running, that way you wouldn't notice the engine filling up when its sits and hydro-locking the block

 

Supposedly you can run the engine with the radiator cap removed and watch for bubbles to see if its a blown HG or cracked head.

 

stroker, you are correct that you can run the engine without the rad cap on but take the cap off prior to starting the engine. otherwise, the coolant will be under pressure when you take the cap off and it will spray out (which does not feel nice).

 

so white smoke is a head gasket huh, hmm that sucks

 

Yes, prior to starting on a COOL engine.

 

Rarely. In my area it's extremely moist and almost every vehicle has white smoke out the exhaust for a bit after starting.

White smoke out the exhaust when it's dry after running for a while however does mean that coolant is more then likely being burned by the engine.

 

Have you done a pressure test of the radiator, and then the cap?
Sounds like the cap is letting pressure/steam escape, which will
boil out the contents of the overflow reservoir.

 

Last time this happened to me on my own vehicle, it took about a week to need to top up the overflow and months for the leak to finally show up.
Turned out to be my Water Pump. Never left any stains near the weep hole 'cause my coolant is Always clean. Go figure.
Not that I'm embarrassed but, I'm a Rad Guy.

You could get some coolant dye. I bought the shop some and we haven't used it yet but I have had cars come in from local garages with it installed. The stuff is an extreme rich-looking green so you probably wouldn't need a black light to spot it.