Used a new ebay coolant reservoir to replace my stock one that had shed a nipple. New one was fine for a week, I think, but is now leaking air and some water between the black collar / fill neck and the clear base. I decided to check the system on a whim and noticed my coolant was low. Refilled and looked for leaks. No hose leaks and bought a new pressure cap so no that either. Let the truck cool and opened the brass refill cap to find and air bubble. So the leak was small enough to let in / out air but no noticeable water. Refilled, ran until thermo opened, out of sheer luck noticed some dampness around where the filler neck and reservoir meet.

Luckily I am running a mixture of only distilled water and water wetter so I don't think it ever overheated but it's ever agrivating to find issues like this after you were certain the entire system was in good working order again.

So anyways, don't cheap out on coolant bottles, get OEM

 

My PN PCF101410 for $37.00 off of eBay has been good for 8 months now. Believe it's a Britpart version. LR original is more than 4x the price and always possible to get a defective one from them too.

Do you know brand you got and have a photo to share?
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Sounds identical to yours, <$40 ebay unit. I'm currently attempting to plastic weld it and fuse the pieces together so a pic wouldn't do anyone any good at this point but I can tell you that whereas the original unit had a nice uniform mating surface all the way around and what looks like a gasket or spacer, the ebay unit has an imperfect mating surface and looked poorly adhered right out of the box but I figured that the adhesive used was more than a micron thick and would seal the sketchy mating if the two pieces

 

Remember looking mine over good prior to install and didn't see anything too sketchy. Looked at neck area again this evening to get better idea of what your dealing with. It's frustrating when our turn comes up to get the defective one. Good luck getting yours back to good working order.
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I just bought a new coolant reservoir and LR 180 thermostat off eBay right before reading this post!
I got them both thru Lucky 8 so I'm sure they will stand behind it.
It was $47 and included a new cap and free shipping.

 

Just got same thing off Evilbay, mine seems to be OK, but the front mounting tab was broken half off from the crummy packing job they did for shipping. Doesn't seem to have affected the reservoir so I just used a bigger washer on it.

My old one leaked every time I drove it. I added water until the new one arrived and kept an eye on the temp. now I flushed it and refilled with the correct coolant mix.

 

Would ask for a refund/replacement as defective even if temp emergency install. If dragged butt to R&R and eBay return not possible join the crowd.

Glad to hear it seems to work.
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