My alternator tensioner started getting weak, so I replaced it with one I purchased from ZZP. When I purchased the tensioner, I also purchased the coolant elbows from ZZP. I went on a road trip, when I returned I noticed coolant leaking on the ground and the leak was coming from the elbows. I didn't think I would have to change the O rings these before installation, I thought it only applied to the Doorman elbows. Luckily no damage occurred from the lack of coolant. I upgraded to the Doorman aluminum elbows and yes I replaced the O rings before installation.
ZZP elbows after removal, notice how the O rings are compressed flat.
Here are the aluminum elbows that were installed and a picture of one that was installed. I couldn't get a clear picture the other one.
I also replaced the upper and lower radiator hoses. Getting to the lower hose clamps wasn't easy, but I got it done and now all is as it should be.