PRIME AC refrigerant O-ring leaks

And then sometimes it’s just a simple oops !?.
Engineer slightly miss calculated the rate of the expansion of the aluminum and selected an O-ring that was One thousands of an inch or 2000s of an inch too small.
It would seal at static pressures and temperatures but when put into operation at a certain temperature or pressure combination start to leak and then went outside of that range stop leaking intermittently.

Other times it will be the manufacture of the fitting for the line or hose when the groove with machined to retain the O-ring 1/1000th” or 2/1000th” too wide or too deep for the O-ring selected

Or the condenser manufacture when boring to receiving hole for the fitting that retains the O-ring goes to slip into its size is just over by a few thousand of an inch.

In all the bug situation it will feel perfectly and hold a perfect vacuum and it will pass nitrogen pressure test it will pass refrigerant leak detector test.

But when put into actual used in the field in the real world as the different materials expand and contract at different rates under different pressures and temperatures a leak intermittently will occur and then the leak will stop went outside of those parameters of temperature or pressure.

 

30+ years ago I used to do that for Honda motor corporation when I worked for Honda and we had filled out paperwork for warranties or pattern problems and they would take the information to see if it was a problem.

 

Exactly! When I had come across these known pattern problems I have several different large kits with several hundred O-rings and I would pick one slightly larger.
I lubricate the O-ring with silicone grease (dielectric grease)
I would also put the silicone grease inside the groove where the O-ring will sit and then mount the O-ring in the groove.
The silicone grease would not only protect the O-ring from oxidation.
But would also fill the tiny air space behind a rounded corner of the O-ring so upon compression it would be a tighter more hydrostatically locked seal.
This was something I learned from my father as a child.
The silicone grease is also used in science and Laboratories when pulling extremely deep high vacuums in equipment they would place it between two mating surfaces and it was an excellent sealant to stop vacuum leaks.

And we’re talking about silicone grease not the tube type white silicone you get in a caulking gun that you use around your windows or for head gaskets.

 

As these vehicles get older two technicians who have never worked on heat pumps the extra valve seal annoyed’s and sensors will be a little confusing as first as these vehicles start to break down

when trying to look up Toyotas factory information on oil charge quantities in individual oil quantities per component I’ve noticed Toyotas on material is incorrect.
Like most of Toyotas sketchy information about hybrid Toyota quantity and what they release contradicts reality.
Apparently the company or division responsible for taking down the correct measurements and posting it in their technical bulletins and service procedures knows absolutely nothing about air-conditioning.
On multiple TSP‘s and service procedures it appears they only copy and paste from older articles that are related. Without realizing what they’re copying and pasting is totally false in this situation on these vehicles.
I released one video before while on Techstream reading Toyota service bulletin on oil charges going down their procedures and adding up all the individual oil per component far exceeded the total oil capacity of the hybrid electric compressor system.
Apparently the individuals in charge of copied and paste in service procedures do not read what they’re reposting and cannot Multiply and addition figure out they come up with a sum greater than the total.

I can almost guarantee 98% when these accumulators get replaced in a collision repair facility the unknowing a knowledgeable technician will just blindly hook up the red hose and the blue hose and turn on the a/c machine and walk away and recharge the system.

Those vehicles will eventually burn up the compressor due to lack of lubricant. It doesn’t happen right away it takes a long long time especially when it happens in winter.

 

Here lies the problem. First they will always deny usually because they don’t get paid as well performing warranty work.

Then there is proof the burden of fault and not being 100% sure there’s actually a leak or placing the full financial responsibility back on to the customer.

If it was me trying to prove this to a dealer I found at the time of testing I could not pick up a leak with a refrigerant leak detectors but not all leaks happen well and vehicle is just sitting there static in a stall running or not running some leaks only happen while the vehicle is driving on down the road under certain conditions.

I will get some degreaser or some high concentrated rubbing alcohol and spray it down and clean it until it’s thoroughly clean I don’t know if you can get in there with your hand and a toothbrush.

Take photo documentation of each one of the joints at the suspected leak and then clean it date it take a picture and in a couple months come back and look at it again.

If the residue comes back and starts collecting dust with oil you surely have a leak then.

When a vehicle is just a little bit low on refrigerant and it’s still under warranty the dealer usually sides with saying there’s no problem found.

But when you’re one day and 1 mile over warranty miraculously they will find a problem to charge you to fix.

There are ways to test and take measurements but since I’ve only had about a dozen of these vehicles to work with so far and most of that was just to charge so the customer can take the vehicle and leave after a collision I have yet to spend enough time to thoroughly test and find temperature and pressure readings across different components that could give me a high enough level of skill to properly test with a high degree of accuracy.

I would to spend a lot of my own free time just for knowledge without charging anybody.
And in the end would end up recovering the refrigerant out of the system so I could weigh the quantity of refrigerant removed to actually come to a conclusion that a system is three or 4 ounces low on refrigerant.

Three or 4 ounces low on refrigerant does not affect low temperature operation for example in the high 60°F to 70°F ambient weather temperature.

Where three or 4 ounces makes a real big difference on a large refrigerant capacity system like the Prius prime is when it’s 85° to 105° and the refrigerant metering device needs to open up to let that extra three or 4 ounces of refrigerant into the evaporator to remove heat but it’s not there that’s when it starts falling flat on its face and has poor cooling performance.

For example if you had a Prius with a refrigerant capacity of 480 g which is just a little more than an ounce over 1 pound.
If you remove three or 4 ounces of refrigerant that would greatly impact the high ambient temperature performance of the air conditioning system

But if you took a different vehicle that had more than 1 kg or 2.2 pounds plus of refrigerant as a charge and you remove three or 4 ounces at that same high temperature you would barely notice a difference. But there would be a difference just to not has a great extent it’s a smaller capacity system

This situation is something to keep an ion for all Prius prime owners if it turns out that many are leaking and it can be documented like the 2016 to 2019 Honda civics in Honda Accord‘s that had the leaky condenser defective problem that later got covered under warranty extended to 100,000 miles 10 years I believe

If these problems are made well known about the Prius prime and can be documented and proved they move can be made to force Toyota to fix correct and cover this under warranty under extended warranty program.

A big company so they will never admit out right that they were at fault they will not make it a recall program they will just call it a extended warranty program or some other wording