Unknown Coolant Device

[Loubiere]

I am experiencing a coolant drip on my 86 C4 L98 when I stop the engine. I can't get to the leak without a lot of work. I was wondering what it does. It appears to have a vent on the left side.

 

[vetteoz]

I was wondering what it does. It appears to have a vent on the left side.

Your photo is clear as mud
but in the location above / behnd the crank pulley you have the water pump
with the radiator and heater hose connections;
ALL are potential major source of leaks when old and worn

 

[WhalePirot]

Your photo is clear as mud

LOL, true. I blew it up and sharpened the pic and still agree!

The leak may not be just upon shutdown.

Is the car losing coolant over time; how rapidly?
Some parts chain stores rent coolant pressure testing kits. Borrow one and test.

 

[Loubiere]

Photo

Sorry about the picture quality. It is very hard to just see. Taking a picture is almost impossible.

I think I will have to move the AC compressor to be able to see what is there.

Thanks for the input.

 

[LLC5]

Sorry about the picture quality. It is very hard to just see. Taking a picture is almost impossible.

I think I will have to move the AC compressor to be able to see what is there.

Thanks for the input.

Follow the leak to it's highest point. I would use a small articulating mirror (like dentists used to use) and with a bright flash light follow the coolant to it's highest path, looking very closely at the water pump weep hole for coolant stains. Good luck with it.

 

[vetteoz]

It is very hard to just see. Taking a picture is almost impossible.

I think I will have to move the AC compressor to be able to see what is there.

Thanks for the input.

After 15 years of C4's , I know exactly what is in there but can not identify what item you are referring to from your pic

Can you identify it here ?

 

[Loubiere]

Leak

I can't see it the picture (nice engine) but I believe it would be attached to the small connection above the main inlet to the water pump.

The leak does not occur while running hot. I have allowed to reach operating temperature while idling on ramps and it dries up. I used dye and UV light to chase it down to that biscuit sized thing. It did not leak prior to flushing and changing the the coolant. I did not use any chemicals. The coolant appeared to have some sort of solids in it.

I decided to try the GM Coolant Tabs and the leak stopped! I remembered GM recommending them in the mid-eighties and nighties. I don't like this solution but until I remove some stuff off the engine, I can't see those hose connections.

Thanks for the picture and advice.