Radiator Question

[rtd111]

First gen 400.

When the engine is nice and hot, both radiator hoses become equally HOT. The "To Radiator" hose first turns hot, and a while later (5-10 mins of idling / test driving at 30mph), "From Radiator" host, which was cold initially, becomes equally hot. From around the radiator, there's white smoke - smell of burning coolant / steam. Can't quite tell where the radiator is steaming - even when I shut off the engine. Its kinda hot to poke my head in there even when the engine is off.

The temp gauge is almost to or barely above normal, but I don't give it a chance to get any hottor.

Had just filled the system with coolant. Has a brand new OEM thermostat installed.

Next steps? Thanks.

[steve2006]

If you are not losing coolant ( the level in the expansion tank is correct) it could just be condensation/spilt coolant ( from the thermostat change) evaporating as steam off the radiator as it gets warm especially as the temp gauge reads normal, with both top and bottom radiator hoses getting warm the water appears to be circulating correctly.

[eatingupblacktop]

Steve2006, what kind of rims are you riding on your LS? From your avatar, they look like BBS. Got any other pics that show them larger? Would like to see them up a little closer if that's possible.

[IS400]

I'd say you have an air pocket like mine did after doing the timing belt. Take off the cover (thermostat) when the car is cold. If you do not have water spilling out when you take it off you are not properly filled with coolant. Turn the car on and get it up to temp so the stat will open and fill from that open cover and then turn the car off and reinstall the cover. That is what I did and it worked. My next question is are you getting cabin heat? If you are then you probably do not have an air pocket IMO.

Remember the stat can be installed improperly too! It has a little wobble part with a hole that has to be lined up right. Call the dealership and ask how it needs to be oriented. I did a timing belt repair write up that tells you the right way, a year ago, but I forget off the top of my head.

Good luck! :)

[rtd111]

Thanks IS400.

I am NOT getting hot cabin air, even at MAX - its outside temp.

After I installed the thermostat (yday) I did refill from the filler hole at the top of the thermostat. It took a little over a gallon and a half before it starting overflowing. BTW, I did all this with the engine running, and I let it run another 3-4 mins after the top started overflowing, adding a bit at a time until I felt no more could be added. I could see the coolant circulating thru.

There already was some coolant in the system (in the reservoir). So the system seems to be full.

But wait, why should the output hose from the radiator be hot? Isnt the radiator supposed to cool the coolant? It might be warm but not almost as hot as the input hose. Any thoughts here?

Even at MAX, the cabin air is is outside temp. In this regard, I felt the temp on both sides of the heater control valve and those hoses were hot. At first, the output did not seem to be but later it did become kinda warm. Yes, I was checking right near the cottle pin and not on the additinal sleeve. HOWEVER, there is an exposed metal pipe just as it enters thru the firewall and that did not seem hot at all, maybe warm but not hot. And all thru this, cabin was set to MAX HOT.

[rtd111]

Turns out there was a slight crack in the radiator. Got it replaced at a shop (I would have done it but did not have time). Problem solved.