Isx15 popping radiator caps

[FnG92]

Just saw the date for my picture of the first radiator cap breaking. It's only been a month, I didn't take a picture of the 2nd time it happened but the whole center of the cap is gone and I can thread it on. How hard is it to do a liner?

[tree98]

Put your radiator overflow hose in a cup of water with the engine running and the cap on so your cooling system is sealed and see if there's bubbles. You might have to up the rpm from idle.

If it is bubbling then empty your air tanks and take your main air line off the compressor. If it's still bubbling you have a dropped liner.

[Waterloo]

That looks more like a manufacturer defect in that cap. When my liner dropped, the cap would simply release pressure. Remove the cap, and it was shooting coolant many feet in the air, like well over the roof of the cab, like a volcano. My point being, if you did just recently drop a liner, I don’t see it building that much pressure to split the cap like that, if you get my drift? That just does not look normal.

[tree98]

Your not putting that cap on with pliers are you?

[FnG92]

The picture I posted I remember really putting that mfer on tight so I bought a new cap and put it on not as tight and my newest cap had the top completely gone like if you cut it perfectly to match the threads.

[Nilao]

Is that a vented cap or a solid cap with the pressure cannon the other end of the tank? I'm wondering if your pressure relief is stuck closed and your pressures are going way to high. Being there is no relief it blows the weakest link.

[FnG92]

That is a non vented cap. There is a pressure release cap that has a nipple that's open on the end of the cap

[tree98]

(12-08-2022 )FnG92 Wrote:  That is a non vented cap. There is a pressure release cap that has a nipple that's open on the end of the cap

Wonder if it's not venting like it's supposed to. Did you put the vent hose in a cup of water to check for bubbles??

[FnG92]

The line going into the thermostat sprays/pushes out coolant and the side going to the radiator fins sucked the cup empty. It's a super short hose so I cut a cup to get into the small space. I did cover my finger over the side going to radiator and it didn't feel like it was building pressure. I'm going to get another cap right now and fill my coolant back up and try the little black hose again.