Hey guys,

After my 300 sits in the garage for couple days, I find small 1-2 inch diameter puddle of coolant. I recently had to change by-pass hose and did a coolant flush. It drips from somewhere above oil pan. My first thought was that I did not tighten the rear engine drain - but i checked and its not where its leaking from. Nothing drips within 6 hours after car been driven but after it sat all night and more, fluid starts appearing on the garage floor. My fears are that head gasket has a small leak...when block is hot (expanded) no leaking occurs, but when it cools down coolant finds a way out. Car runs great, no loss of power or anything like that. Coolant is clean and oil has no coolant in it (thank God). Please let me hear your thoughts/ideas on this. Thanks

 

Clean the floor and the engine (from below). Then trace the point of drip ... all the way back to the source.

You can go to radiator shop, who can do the pressure test for you (both hot and cold ,,, but lot easier to do when cold).

Salim

 

More than likely what you have is fluid seeping out of the overflow canister. As you stated above you recently did a coolant flush. Until all the pockets of air work their way out of the engine you can get burbs from the overflow.

 

The easiest way to find out is by pressure testing. If it leaks when it's cold, that when to test it. Putting about 20 lbs. of pressure on the system (it should be able to tolerate that) will reveal leaks in a way that normal running (or sitting) isn't likely to. If the pressure starts to drop, start looking for the leak. GENERALLY leaks are more likely to show when it's warmed up good, and you may even find out that by putting 20 lbs. on the system that leaks DO show up when it's hot, though they don't when you've been running it. 20 lbs. is a little more than the cap is rated for or is normally on the system.

 

Look carefully on the drivers side of engine. Near the Thermostat housing and see if there is red residue there. mine was a leak from intake manifold. Did you use new gaskets when replacing the bypass coolent hose when removing the intake manifold.?

 

Thanks everyone, I been busy for awhile but wanted to say thanks for everyone's input. I'm truly thankful to all on this forum who is willing to help others at no cost. Sadly enough the leak was in head gasket. I was really bummed out since i just bought this RX is April and did bunch of work to it. Anyways, since fixing it the right way is not an option right now I had to use Bars Leak Head Gasket & Cooling Sealant. I was very hesitant about putting this garbage into my just flushed and topped off with expansive red toyota coolant but after sitting on this idea for couple days I decided to go ahead and put it in... it worked. Not a single drop of fluid so far - its been almost a week. So my question to you guys: should I change coolant now to get rid of unwanted sealant or just drive like that? Instructions on the bottle say nothing about flushing the system or anything like that. I want to clean up coolant but at the same time I'm afraid of undoing the leak.

Thanks

 

How did you determine head gasket.? Are you sure it isnt the intake leaking...I though mine was head gasket also, but was the intake manifold gasket...There is a water passage through part of it.

 

It should say on the can or bottle, but I believe you're supposed to leave it in there. That type of sealer is "air set", meaning it does not set without air getting to it as a catalyst. That's why it only sets where it comes in contact with air, either in the combustion chamber or outside of the head in the case of a head gasket leak. There should be a phone # on the can and they are happy to talk to you and answer any questions you may have. You don't want to take it out if it doesn't clog the system (shouldn't) and it will be there to stop any other leaks that might develope. I have used it in the past with excellent results. It usually lasted 4 to 6 months and then you just do it again. Never was any sign of clogging as a result of using it.