engine coolant leaking

I have a 2013 Prius C. My engine coolant is leaking. I lose about a quart in 1 week in expansion tank. There is always a puddle on the bottom plastic cover. Today I hooked up a pressure tester. It drops from 20 psi to 15 psi in about 3 minutes. I don't see the leak, but the puddle forms around black round bottom support on the passenger side. See photos. The foam radiator support seen through the hole is also soaked. The puddle starts to form about 1-2 min after pressure is set, so it probably comes from the top coil (engine, not the inverter). The inverter reservoir stays at the same level.

It looks like I need to replace the radiator. What do I need to remove to get the radiator out? Are there videos or pictures for Prius C radiator removal? They would really help. There are posts on this forum saying that bumper removal is not necessary. Is it necessary to drain the engine coolant, or just draining both radiators is sufficient?

Thanks a lot.

 

Thanks a lot! This is very helpful.

 

The radiator replacement is done. I want to share my experience. Hopefully, someone finds this useful.

It took 4 days. It is not difficult, but some steps are very annoying. I live in Massachusetts and close to the ocean. I enjoy road salts all winter. I also enjoy salty sea spray all year round. It means a lot of rust and corrosion.

Day 1:

Jacked up the front, supported the front with 2 jack stands with front wheels about 3 inches off the ground.

Removing two bottom plastic panels was difficult. Front screws through the plastic were ok. The 2 bolts on each side in the wheel wells were completely seized. After a lot of WD40 and back and forth the rear bolts on each side came out, but both heads on the front ones sheared off. There was almost no metal left under the heads, the bolts were maybe 2 mm thick. After about 40 minutes of trying to punch the centers and drill them out I gave up. The good news - the covers were off.

The hood lock and reinforcement bar were easy to remove. 10 mm wrench and a hammer to get started is all I needed. Both plastic clips broke even though I used the proper tool. I needed to disconnect the fan, which is the top connector. The connector clip broke no matter how gently I tried to push on it. Removed grey duct tape holding the fan wire to the shroud. Unclipped this wire from the metal support on the passenger side. Then the support bar and hood lock can be flipped over and onto the engine/inverter and out of the way.

Next is radiator support bar. 2 bolts, very rusted, almost no metal left. I struggled with them for 15 minutes but was able to get them out.

Drain the coolant. Inverter coolant was easy. I used a 3'-long hose to drain engine coolant from the radiator. I think, the hose is 5/16''.

Disconnecting the hoses. Inverter passenger side was not too bad. I used small pliers and was able to wiggle the clamp towards the elbow. The driver side was a nightmare. As soon as I squeezed the clamp, it snapped right at the 90-degrees bend leaving me with a fully locked clamp and nothing to grab onto to squeeze it. It was heavily rusted. I struggled for another 20 minutes, tried to cut it off, but nothing worked. I gave up and decided to pull the radiator out with that hose attached and deal with it later. Unlocking both inverter hoses from plastic tabs and the expansion tank is not too bad, but a few plastic tabs that hold the hose supports also broke. The large clamps were also rusted and very thin at the bend. One clamp also broke before I even squeezed it. So, I decided to replace 4 large clamps I could easily access. I plugged the hoses so coolant would not leak out.

Getting the radiator out was the hardest part. At first, I did not even understand how to push the condenser up and forward - there was no room. Then I pushed the entire shroud assembly (with radiator and condenser) up, back, and then a little down so that the shroud support legs clear the metal frame. The condenser's feet sit in the shroud support, so it needs to go up to clear these feet and then forward. Then the radiator/shroud assembly comes out. It took a lot of wiggling. The hardest part is to clear the AC piping by the inverter inlet on the passenger side. I was able to lift the assembly to that point, and then go under the car and firmly but gently push on the AC pipe while clearing the radiator bottom inlet on the passenger side. Finally, the shroud/radiator assembly was out. Separating them is easy. Keep in mind that there will be leftover coolant in both radiators, don't spill it. I removed the inverter hose with the broken clamp by using large channel lock pliers, but it took a lot of wiggling, and I was seriously worried about damaging the hose.

Day 2:

I needed new clamps, but the dealer was closed. So, I vacuumed and cleaned everything around the condenser, shroud, and attached the new radiator to the shroud. Putting it in took just 15 minutes. Putting the condenser back into the shroud support took some effort. Routing hoses was easy.

Day 3:

Toyota dealer does not have engine radiator clamps in stock, only inverter clamps. Installing the inverter clamps was not too bad.

Day 4:

Got the new large clamps from the dealer. I don't have the Toyota clamping tool. I could not close them while they were on the hose. I could grip them with pliers or vice grips, but I could not disengage the locking tab no matter what I tried. So, I put them on a concrete block, hit the tab with a nail finisher to make it close, and then grabbed them with large channel lock pliers and installed them onto the hose while connecting the hose to the clamp. Inconvenient, but not too bad. It is important to install new clamps (both engine and inverter hoses) exactly to the marks of the old clamps, so they don't leak. So, after releasing channel lock pliers I rotated clamps to match the pattern by holding them with small pliers. Annoying and tedious. Often, there is no room for the pliers.

Putting things back together was easy. Got new bolts for radiator support bar from the dealer. Did nothing with the front bolts of bottom covers.

Filled up coolant into inverter, engine, and expansion tank. Started the car a few times, added coolant as needed. Everything seems to be running fine.