Hey guys,

I figured I'd start a new thread and move away from the thermostat flip thread since this seems to be a different issue.

To recap with as much information as possible.

I did my timing belt couple weeks ago. I replaced my all my belts, cam seals, front main seal, and oil cooler seals. All areas I had oil leaks from and those are all good to go now.

I also replaced my upper and lower radiator hoses, and my oil cooler coolant hoses. Keep in mind, I didn't Replace any of the clamps. STUPID, I know.

Everything has been great.

Two days ago I replaced the radiator cap since the old one had cracks on the rubber seal. I also topped off the coolant and filled the reservoir to the FULL line.

I drove to work yesterday morning and once I got there noticed that the there was coolant leaking from the where the reservoir hose connects to the side of the radiator cap. I figured I had just spilled some coolant so I cleaned it off and moved on.

After the drive home I noticed that there was no longer coolant at the hose, but rather at the top edge of the radiator where the plastic meets the metal. I cleaned that off to verify again.

This morning before I left to work, I noticed that the coolant had leaked along to top edge again. But I also noticed that the reservoir was at the half mark between full and minimum.

Today when I got home I noticed that the top of the radiator was now dry. It hadn't leaked from the radiator at all. I actually had a puddle of coolant right under where the lower radiator hose meets the bottom of the thermostat housing.

I got under it and found that it was NOT leaking from the top of the thermostat housing. It was actually leaking from the where the hose connects to the metal. Like the clamp didn't have a good seal. I grabbed the clamp with my pliers and some more coolant dripped down. I adjusted the clamp. The reservoir was at the middle.

And finally when I removed the radiator cap. Coolant spewed out and the reservoir bubbled and came back to the full line.

At this point I don't know what's going on.

The system seems to be building pressure and for some reason that pressure doesn't over flow into the reservoir. It's releasing it at other points like the hoses and radiator.

I also want to point out that the day before I put the new radiator cap on, I flipped the thermostat from 12 o'clock to 6 o'clock. But i can't imagine this is the issue.

The truck runs at 188.6 consistently. So the thermostat must be opening. Besides it's brand new.

I'm at a loss now. My wife and I just had triplets and my time and money are really limited.

Any help would be truly appreciated...

 

It could be that the hose clamps are not tight enough, once it's under pressure it pushes coolant out. The system has to build enough pressure against the cap to go to the overflow tank, it's probably just leaking past the hose clamps first.

 

Should I have replaced the clamps. I was trying to save a buck and didn't really think they weren't reusable?

I can replace the clamps and the radiator now that it leaked, but I'm also afraid that if it's not releasing pressure correctly, then it may affect the Heat Gaskets.

Am I wrong? I'm not really an expert with this stuff.

 

If it is clamps needing to be tightened . Does it still have the factory spring hose clamps ??

Unless you went with Toyota for your radiator cap the aftermarket made in China ones can be hit or miss as far as quality.

 

Yeah. Pretty sure it's the original clamps. But I bought used and have had it for six years. But all the clamps look like oem. So they can be very old.

The cap is Toyota OEM.

 

I would guess Yos it is the clamp. Over time the clamp can lose its tension, especially when it is exposed to rust. It may just be a simple clamp which can be replaced easily.

I personally would go to an auto parts store, rent a pressure tester, pump it up to the bar pressure on the cap, and see if you hear or see the coolant leaking out.

Congrats on the triplets!

 

Thank you J2F42C! It's life changing having unexpected spontaneous triplets.

I'm going to get new clamps and pressure test the radiator to see of it is leaking. If it is, I'll replace that.

Then the whole system will new from hoses to thermostat to water pump and radiator.

Hopefully, this doesn't cause the pressure to move somewhere else like to head gaskets or heating core.

I feel like I should put the old cap back on since it wasn't leaking coolant and never overheated.

 

So I replaced the radiator and all the clamps and kept the new radiator cap on and it hasn't leaked in a couple days.

I guess the new cap was properly pressurizing the system and it was trying to find the path of least resistance.

Thanks guys!

 

I just changed my timing belt, water pump etc and found the hose clamp was off at the wtr pump/oil cooler connection. No leaks for over at least 60k miles.

 

Cheap solution $9. Rad cap on right missing pressure regulation flange caused leak through reservoir.