My 2006 LS430 (119k miles) has always seemed to lose a little coolant. The level in the reservoir has always seemed to ever so slowly drop. Over a year ago I replaced a leaky radiator. Still losing coolant. I used screw hose clamps, and I have had to tighten them up a bit every so often. A few days ago, I noticed just a 'tiny hint' of coolant smell. So I popped the hood. My coolant reservoir was empty, the car was at operating temperature.

I took off the plastic part that covers the radiator, and took off the engine cover. I have attached a link to a video which shows some measurable evidence of my coolant leak.

Hopefully someone that sees this video can tell me which part is leaking, and what needs to be done to fix it.

I give a more complete explanation of the situation in the video.

Thanks for reading my post, and thanks in advance for checking out the video.


Here is another video which includes some commentary with a mechanic friend of mine;

 

When you pull the engine cover and look down at the top of the throttle body, there are some hoses/clamps right in the area above where you are pointing to in your first video. Make sure those hoses and clamps are good and there is no leaking from there. I think your leak might be coming from above.

 

Spend the money on a proper OEM hose clamp, they are only $10. Part number 9613654801

How old is the water pump and what brand is it?

The part you're pointing at is the Water Inlet Housing, part number 1603250110 which is a $53 part from Partsouq. Before you fire the parts cannon though, you might consider doing a pressure test on your cooling system and see if you can pinpoint the leak...

 

Romanova is pointing you in the right direction with the water inlet housing. This part has 3 gaskets, 1 is an O ring, 1 on the thermostat and the rectangle which you may have to make with gasket maker. Pull the housing off and replace all 3 as well as the thermostat, while you’re in there, this will also give you the opportunity to inspect each hose and clamp connected to the housing.

 

Yep, I think it's your water inlet housing!

 

Can someone point me in the direction of a gasket & oring kit for this water inlet housing?

 

The rectangle gasket comes pre formed with the new part. If yours is compromised you can carefully remove the old and use gasket maker for a new seal.
The O ring is part no. 9676135035