'97 Camry 4 cylinder coolant leak

[Bubbajet]

I have a coolant leak at the bypass hose on the back of the cylinder head. The leak is at the fitting that is attached to the rear of the cylinder head by another pipe that also connects the heater hoses to the engine. It is at the bottom and the hose goes to the pipe that runs back to the thermostat. I have used a new hose and tried 3 different types of hose clamps ( one from Autozone made in China, another from NAPA don't know where it is made, and another from BMW made in Germany) to secure the hose for a leak free connection. After the repair and running a few times that day, the hose is dry. The day after the repair, the hose is damp and you can see coolant that has dripped on the transmission. I cannot determine if the leak is from the hose connection OR seeping out of where that hose fitting is pressed into the pipe fitting which also connects the heater hoses and 2 sensors, since I can only see around the connections with a mirror and light. How often does the fitting leak where it is pressed into the pipe coming out of the back of the cylinder head. Is this common? Thanks.

[hill8570]

Can't say that I've ever seen the metal pipe / engine fitting ever leak. Doesn't mean it can't happen, but it can't be common.

You may've overtightened the hose clamp -- common problem with the screw-type clamps -- tighten too far and drip, drip. As big as a pain in the ass as the OEM spring clamps are to get on / off, they don't have that problem. Remember, the clamp isn't there to seal the hose to the fitting, it's just there to keep the hose from popping off over the flared area on the fitting.

You can get some goop (name escapes me at the moment) that you can smear around the inside of the hose before attaching to the fitting that will help the hose seal to the fitting. Normally not needed the first time the hose is attached, but if you do multiple pulls / reattachments of the same hose, it helps things reseal. Won't help if the i.d. of the hose ain't right, 'tho.

[toyomoho]

Have you checked to make sure the hose is not failing? A hose can start to fail without bursting, the result is a drip or damp hose.

[Bubbajet]

I did not mention in the original post that the hose is brand new from NAPA Auto Parts.

[Bubbajet]

Also, after replacement of the bypass hose there is no leakage. The car is diven a few miles and up to normal water temp, I check the hose and it is dry. The next day when the car is cold, the hose is wet and the coolant has dripped on the transmission.