Help with an antifreeze leak

[gtg737m(3)]

Yesterday I was changing the temperature sensor and thermostat of my 1994 Volvo turbo station wagon. Before changing these two parts I released some antifreeze from the back hole of the engine block located on the pasenger's side. After cahnging the thermostat and the temperature sensor, I poured some antifreeze in the container that indicates the amount of antifreeze in the engine and all antifreeze that I was putting in the engine leaked from the top of the oil filter. I cannot really tell where the leak is exactly located but I can see that most of the antifreeze is pouring from the top of the oil filter. I didn't touch anything in front of the engine with the exception of the thermostat housing(which isn't leaking) and te temp sensor. Is there a specific procedure that I must follow to put the antifreeze inside the engine? Before releasing the antifreeze of my engine my car had absolutely no leaks. I would appreciate a lot if anyone here can help me solve this problem.
Thanks: Theo

Email:[email protected]

[White850Turbo]

It sounds like your water pump could be leaking. Take off the plastic cover and inspect it a bit more closely.

[gtg737m(5)]

I decided to take my Volvo this morning to the dealer and I was told that the thermostat housing is cracked. I think that the thermostat housing was cracked when I bought the car but that problem was covered with some specail epoxy that was applied around the housing to avoid leaks. I guess that when I removed the thermostat I moved the housing too much and thus it started leaking. I'm being charged $650 to change the thermostat now that the intake manifold needs to be removed to have access to the thermostat housing bolts.

[Guest]

$650 is OUTRAGEOUS. Get a second opinion/cost.