Will someone please give me the $1 education in what systems the three radiators are connected to at the front of the van?
1) I have the primary engine coolant radiator identified.
-- Am I clear that the engine oil has a pipe that runs through the primary coolant radiator as well?
2) What is the large area radiator in front of the primary coolant radiator?
3) What is the small area radiator in front of #2 above? Refrigerant?

This all comes from my searching for a small coolant leak. I am loosing a cup, 8oz, of fluid every 100 mi (+). It is summer and has been hot.

- I did found an overflow(?), pressure relief(?), hose coming from the top driver's side of #2 above that is dripping a small amount. I have no idea if it always has dripped a small amount.
- Is there a hose from the main coolant radiator running to the cabin heater? I am assuming it would be running to the blower area.
- Other reading directs suspicion to a coolant connection at the "back" of the engine. I pulled the cabin engine cover and can not find any coolant hoses running to the back.
- I am starting to suspect the radiator cap.

Thank you

 

if im understanding you correctly, the three "radiators" are the coolant radiator, trans fluid radiator and ac condenser.

as far as the coolant leak, theres way too many possibilities to even guess. the only way to know is seeing a wet spot. if you suspect the heater core in the dash you can bypass it by looping the hoses and seeing if it stops leaking. you can also try a UV light, it will depend on the type but some coolants are UV reactive and will glow with a UV light. if yours in not you can add some uv fluid to the system and seeing if it pops up. you also could be leaking in the engines combustion chamber, a puff of white smoke when you first start a cold engine is typically the first warning sign of this. you can also test the coolant for exhaust gasses. i dont know too much about the vans but there should be a rear heater core also, i know you said you looked so there might not be one.

 

[QUOTE=Irish_alley;515186]if im understanding you correctly, the three "radiators" are the coolant radiator, trans fluid radiator and ac condenser.

What would be dripping from the trans fluid radiator hose?

 

[QUOTE=tbb2;515199]Not sure, take a picture. Don't know of a trans cooler that has a pressure relief.

 

What you're referring to as #1 (closest to the engine) is the radiator. #2) The large one in front of the radiator, is the AC condenser. If you see green oily liquid coming from it that's refrigerant. #3) The small one in the front is the tranny cooler.


You can get a cooling system pressure tester from some auto parts stores on their tool loan program. It's pretty simple to use. It will have a bunch of adapters, one of which will attach to your radiator fill neck. You attach the included hand pump and pump it up to about 16psi (it has an attached gauge). With the system pressurized it will leak just like the motor is running and hot. You can safely dig around in there and find the leak.

If it's leaking from the cap you should see dried coolant around the cap area. It looks like a white residue left behind as the coolant collects and evaporates. It will only leak from the cap while the engine is at operating temp. You can cover the cap and neck with a paper tower held with a rubber band and take it for a long drive. If it's wet then steam vapor is leaking from the cap. If you're in doubt then just replace the cap. they do wear out and leak under pressure.

 

Irish_alley

My Bad. I did not follow the lines correctly. The dripping hose comes from the radiator expansion tank.

 

The expansion tank and hose aren't pressurized. It could be the hose coming apart. Should be be easy to figure out.

 

It is not the radiator cap.

I did find a drop of coolant on the bottom of the oil pan.
My best lead now is the water pump is failing and I need to get underneath to confirm.
It is soaking wet and freezing here now so I am doing preliminary study on replacing the water pump.

First off I am reading there is no drain valve for the coolant.
I do see a reference to an engine block coolant drain that I assume is not the low point and the radiator bottom hose still needs to be pulled.

I am finding various pics of the engine block drain plug but they are to close up to narrow down its location.
Would I be on the right track to pull the passenger side front wheel and well cover to get to the plug ?
... Or could it be reached from the bottom ?
If I pull the bottom hose of the radiator, and there is coolant trapped in the engine block, how much fluid might that be ?

On a previous sedan I flushed the radiator several times, after draining, by filling the system with tap water, running the engine to operating temp w/ the heat On, letting it cool and repeating.
I'm thinking now that may not be a good idea, but it would flush the coolant out to the engine block.

Advice ?

 

I don't like "flushing" because you can't get rid of all that tap water. Never use tap water. If you want to buy a few gallons of distilled water and flush go for it, that would be a good thing. It takes a big hat most people don't have. Mine didn't get shipped in until after I replaced the radiator so I haven't taken it off. There is one on both sides I think. One is "hiding" behind the starter.

 

I will assume the "it" is the engine block coolant drain.
How do you know there is more than one?