This is Why Stop Leak Should be Banned

Yeah that's very common it'll even INFlate up out filler neck . Really wild looking stuff usually. Pulling rad and presxur flushing all else . Sad

 

In other words, if you don't know vehicle history of a gen3 and you're swapping or rebuilding the engine you need to decide it you're replacing the radiator or not...

I wonder if there's a flow rate test to determine if radiator is viable? Anyone have an suggestions?

 

generally, by the time the over heating light comes on, the engine is blown

 

It is very likely the flow into the reservoir tank will be higher when the radiator is partially clogged. This flow can be observed and could be measured.

Radiator and reservoir flow starts when the thermostat opens. Before then, only flow through the thermostat bypass port to the engine occurs.


The reservoir flow parallels the radiator but does not go through the cooling channels of the radiator.

The flow restriction caused by the radiator micro channels creates pressure differential driving flow into and out of the reservoir.

 

One stop-leak manufacturer recommended a flush with 50/50 white vinegar and water, might help.

I totally agree: stop-leak products should be banned. They're ostensibly to eke a few more miles out of a head gasket, but a ploy too easy to use when selling to unsuspecting buyers.

Hey, maybe Toyota should market a stop-leak product, specifically for 3rd gens...

 

Has anyone found a way to modify their Prius so you get a warning at a lower temperature?

 

not that I recall, but as o/p mentions, a cheap old reader works fine

 

Sometimes I think you just unblocked me


$35 P10 with user set audible alarm on temp. Probably posted 15 times here.

 

Use an IR temperature gun to shoot different areas of the radiator. Deviations should be small, clogged area deviations are larger. This is a lot faster than pulling the radiator to flow test it.
You can also pull the lower radiator hose to inspect for jelly like gunk...... There should be NO contamination.

 

I added an IR imaging camera to my toolset a while back. Just a small little thing that plugs into my phone. I don't think I'll ever need it to show radiator blockage, but I did test it on my warmed-up car. The HVAC condensor is first in line, viewing through the hood latch access port. With A/C and both radiator fans running, the temperature was very uniform across the condensor. I imagine reduced airflow due to obstructions (bugs, etc.) would appear warmer. It would be difficult to image the ICE radiator though, since it is behind the HVAC radiator.

 

You shoot the IR gun from the engine side. Shooting the AC condenser doesn't tell you anything other that it's condensing.

 

Head gaskets have been a problem since 1919, surprised we still haven’t solved it

 

As saying goes about a picture being worth a thousand words... A thermal image camera is going to give way more information than an IR gun that can only give one data point at a time.

 

I did a quick look of your past postings and can't find a build thread, any link to it? Does that hook into an OBD2? That's pretty cool. I'd like to do something similar myself with some other info as well if possible.

 

The P10 plugs into the obd2 connector which is constantly powered. So you set it up to sleep after 180 seconds of no rpm and reduced voltage.

I use it to display coolant temperature which for a Prius is the standard block sensor. It is set for an early 220f audible alarm. I also set a 78 mph speed alarm.

There are display options such as two or more parameters.

See attached

 

Toyota solved it over the past 40 years by selling vehicles that could consistently get way past 300K without a need for a new head gasket. Then in 2010 Toyota got the stupidest idea ever of putting a bigger engine in a Prius and it took them till 2016 to fix all the shorter engine lifespan problems that it created.

 

Gen3 was value engineered by Toyota to reduce costs and maintain the price point under deadline pressures.

The gen3 engine was not specific to Prius from 2010-15. It continued in North America through 2017 in the Prius v and worldwide through 2021. The later engines with revised pistons, rings, intakes, egr valves and ecm software run fine without excessive oil burning.

All these parts are available for older engines. All these parts except the ecm software come with recent JDM $1200 engines.

 

In this day and age the easiest thing is a photo with a FLIR camera. One quick look and you'll see distinct hot and cold regions of the radiator.

Those cameras used to be terribly expensive, but some models are now under $100 and dropping.

 

The problem with ir on a Prius is the front is covered with the ac condenser and the rear is covered by the radiator fan assemblies.