Bocatrip

I took my 01 LS430 with 103K into my local shop, had the system pressurized as well as the radiator cap tested. Everything checked out fine other than a loose lower overflow hose clamp. I had it replaced. Although I do not have any leakage on the floor or the pan cover, I get small white dot stains around the black coolant reservoir and some on the fan shroud. I've had this since I purchased the car 8 months ago and never see anything wet. The coolant level is correct which makes me think it is an extremely small leak. I keep thinking it is the reservoir but never see anything wet. All hoses look good. Can the reservoir have a pin hole leak? Any clues?

Jabberwock

I don't know if the reservoir is pressurized. Based on past experience when I have seen the tiny white dots in my car it has been a tiny pinhole leak in the radiator that may only be spraying when hot and when car is being driven. The leak will usually get slightly worse over time.

jimbosr1

if you dont know when the rad cap was replaced,change it $12 at a parts store.it may pressurize good but still can leak small amounts while being driven.rad caps should be replaced often.if it still leaks your out $12

Bocatrip

I took most of the fluid out of the reservoir and I'm still getting the white dots and staining around the black reservoir. I'm starting to think it is NOT leaking from the reservoir. I can't see it leaking anywhere from the radiator or anywhere else and hate to change something unless I know for sure. I get the white dots when the car is hot and driving on the highway. Does anyone know the cost of a new radiator? Does it have to be OEM or can it be aftermarket? I see very cheap prices on Ebay for new radiators (aftermarket) for around $100. I've been driving like this for almost a year and the fluid level stays the same. Must be a super tiny leak.

jimbosr1

your rad cap is in front and above your overflow tank.i go back to my prior post,change your cap!

Bocatrip

I forgot to mention I changed the cap last week! Thanks anyway. It is super difficult to locate a pinhole leak in the radiator and to change it and find out it's good becomes an expensive mistake!

jimbosr1

you can put a dye in the coolant and use a black light to find it.same black light we all used in our hippie days.

Bocatrip

Thanks Jimbrosi1. I remember the Hippie days and the black light but not much of anything else! lol Everything seems to be pointing towards that pinhole leak. Anyone have any luck with aftermarket radiators for the LS430? OEM are super expensive..$450+. I see the aftermarket ones on ebay (one row) for as low as $100 for aluminum core. I believe the brand was Performance Radiator.

jimbosr1

you can try a auto salvage yard.they will get you one and pressure ck it for you.may be cheaper.

lex2001

I seem to recall a similar post not too long ago about a mystery coolant leak. That poster determined that one of his hoses had the pinhole leak but only expanded enough when it was at max temp for awhile to expose the hole. I assume you have already taken the car on the highway gotten up to operating temp for awhile and then pulled off the road and opened the hood to see if you can find the leak. Another thought would be to tape paper or gauze on the radiator and see where it got wet. I don't think it is hot enough to be a fire hazard. Ignition temperature of paper is 450 degrees and your radiator only runs at half that temp.

Bocatrip

Great suggestion but the fan assembly and shroud makes that somewhat impractical. I pulled over various times but nothing ever gets wet, just tiny little white dots almost like dust particles. The fans have a way of making any leak fly in different directions making it almost impossible to locate.

jimbosr1

you could try some talcum power.dust it on then blow some off then take a drive and see if any area gets wet.thats what we do on aircraft to find leaks.you can wash it off when your done.

Bocatrip

I like that one. I could probably use one of those dusters for gardening to spread insecticide around. I took every drop of coolant out of the reservoir virtually eliminating that as an area for leaks. Thanks for all the suggestions.

Bocatrip

I just took a look at the radiator and fan/shroud assembly and due to so much obstruction it would be really difficult to get around everything to dust not to mention finding a leak behind the fan/shroud area. It's not like the "old days" where there was nothing in front of the radiator.

randal

Did you take it to the local Lexus shop or a radiator shop? Although most shops are fairly competent, you really need a good radiator shop. I would drain and pull the radiator, take to a radiator shop and have them pressure test it. If there is a pinhole leak, they will find it and can probably repair it on the spot too. If that shows nothing, put it back together with new hoses.