Roop10

I just noticed over the past few days that our RX300 is leaking antifreeze. I had to do an oil change yesterday and clean out the PCV valve and while i was under the car is when i noticed the leak, while jacked up in the front, it was running down the backside of the motor on the passengers side and dripping off of the top of the oil pan directly above the drain plug. I cant pinpoint the leak nor do i have a vacuum test kit to put on the radiator to find out where its coming from, with 195k miles i'd say it could very well be that the coolant hose under the intake could be bad? Its a steady drip, about every 3-5seconds it will drip. Any and all help is appreciated, thnx in advance.

salimshah

Just jack up the RX and get some mirror and light and look for the leak. Look for the crust whitish-pink (if you use Toyota Red).

If it is from the firewall side then it could be the hose leading to the heat-exchanger. If it is from the block side , you will have to do more searching. There is a cross over hose that goes from the left to the right bank ... [see the knock sensor diy]. That one is buried deep. Just trace the trail.

What you mention is called a pressure testing kit. The nice thing is that you dont have to have the engine running and hot and simply build up the pressure. Please dont ever go near the psi limit on the radiator cap. I would say stay 50%.

Salim

Roop10

Thnx, i use reg. green antifreeze. It's coming down the backside of the block, my fear is that its the hose under the intake manifold. I'll have to locate my telescope mirror and see if i can locate the leak. Is there an advantage to using Toyota's red coolant verses green?

salimshah

Liquids due to surface tension and flow of air do not follow direct gravity path. Also I tend to look at simple hose leaks ... but you know the block has channels and gaskets can leak.

The only place that I know of the coolant track would be to the IACV and the cross over [my limitation]. IACV is on the driver side, so ...

Harbor freight seels a mirror on flexible wand.

I have not done any comparative analysis and have stayed with Toyo Red ...

Salim

hypervish

Check around the thermostat housing as well.

Toyota Red & Pink offer much better corrosion protection than green coolant. Coolant passages look like new when using the Toyota stuff, but the cheaper generic garbage will end up making everything crusty and gross.

fastnoypi

Probably 10 years back, i would agree but alot of the major manufacturers of green coolant are now HOAT compatible and perform the same as Toyota fill.

Red is a pretty old formula which has 30k replacement intervals. Pink is much better and good for 100k intervals.

Roop10

Noticed that it leaks when car is off and cooling down, drips every 2-3secs.

Roop10

Is the bypass hose the name for the hose located under the intake, the one by the knock sensors? Also what brand is OEM Knock sensors, thermostat and timing belt and components?

Roop10

Also, when i find the pink anitfreeze, do i need to do some sort of a coolant flush or just drain the green out and tighten drain plug back and add the pink or do i have to do a flush somehow? And where is the best place to go to get the pink antifreeze, toyota or autoparts store?

fastnoypi

If you currently have green coolant, you can drain and fill with distilled water and drain again for a flush. Get it up to temperature before the final drain so any green left will get circulated.

If you want specifically Toyota pink get it at your dealer parts counter.

A popular alternative meeting Toyota's HOAT compatibility is Zerex Asian formula. Can be found at NAPA and Advance Auto

Other compatible alternatives that can be found at some other auto stores and amazon..

Pentofrost A1 and A4
Beck/Arnley Red concentrate or Pink pre-mix
Recochem's "OEM Premium" Red concentrate or Pink pre-mix
Aisin Pink (50/50 pre-mix) "

salimshah

Price the pink from Toyota. I prefer the price of the Toyota Red concentrate + H20

Salim

fastnoypi

for a little more initial spend the pink is cheaper in the long run with less services needed if no issues with your cooling system between intervals. Red LLC, has a required change interval of 2yrs or 30k miles, whichever comes 1st. Pink Super Long Life Antifreeze Coolant, SLLC, has a required change interval of 50k/5years, after the initial 100k/10yrs, whichever comes 1st.

On other forums it is mistaken that mixed Toyota red with water equals Toyota pink. They are different formulas.

tllee

Totally agree. I started using green coolant(Prestone, Peak, Walmart, etc...) 7 years ago. I changed my timing belt, water pump last year(use green for 70000 miles), water pump look like new, no crust ,deposit ,etc....
Hey, manufacturers guarantee it to meet factory warranty for a reason(they don't like to fool with their money and reputation). I use it even on my Honda(their manual strongly warn not use anything else), same result when I changed my water pump and thermostat.
I use my cars as the lab rats, it prove the manufacturers just try to make more money.