go buy the appropriately sized worm gear clamp, they are easier to use and can be tightened if a situation like this pops up.

 

Thanks. Will do that as slipping the line in only lessened the leak a bit. Assume the constant pressure clamps give over time.

Why does the leak happen some time after the car is shut off, is pressure built up?

 

Yes, use a worm clamp, like the ones pictured below. I would also replace the hose. 5/8 heater hose sells for cheap at the auto parts stores.

Edit: Sorry, missed the fact that this had been answered already

 

I clamped the lower hose behind the wheel well [going to the rear HVAC] with a turn key worm clamp, only to discover there is another leak higher up in a Y connection.

Seems this would work - http://www.ebay.com/itm/Heater-Hose-...ZUmmQV&vxp=mtr Seems the existing hoses glued into this junction?
One hose goes across the engine, one goes down to the rear plumbing and the other is connected to the second water pump.

Not sure if I have enough slack to cut the hoses and reattached with clamps.

 

That was the problem with ours. Yes they are glued or fitted to the Y connector. I didn't buy the new part it was to expensive so I found a better and much cheaper solution. It costed about $4 at Lowes. Let me go out and get a picture to show you and I will send the link for what I used. I just replaced the same line that you had a leak from because I had a leak there too.

 

I think I found it. The hose going down the wheel well to the rear seems smaller, assuming 3/4

http://www.pepboys.com/product/details/595470/59/

So newb question, what's the best way to cut the hoses? Shears, box cutter or this pricey gadget? I see i have slack 2 on the longer hoses but the really short one going to the aux pump i might need to replace.

 

If you cut the other two off and disconnect the auxiliary pump you might be able to pull it out of the Y it'd tough but I managed to get it. I used tin snips to cut the lines but anything you got would work just clean the end up if it's not straight.

 

this ? - http://www.lowes.com/pd_83488-137-CL...d=3506830&pl=1

what is the size of the hose going down the wheel well the to the rear- 1/2 or 5/8, looks smaller than the other 2 and what is the official part #? I suspect the T or Y needs to have a different ID size at one end.

 

It is 5/8 hose and let me find you the link for it, just a minute

 

The link you posted is not the right part. It's a copper reducing T fitting, size 1"×1"× 3/4". Still trying to find you a link.