Coolant leak

Hey all, I’ve got another prob with my new to me 4Runner.

We did a coolant flush since the radiator had rusty water in it. We used the Toyota pink stuff and glad we did. Now we have a leak coming from the back side of the motor. It appears to be dripping onto the top of the transmission bell housing. I’m assuming it’s a head gasket issue but wondering if there are any hoses or other connections back there that could be causing the prob.Hard to see in pic but you can see some of the pink stuff below the exhaust manifold.

 

Are there any heater hoses in that area?

 

There is one at the back of the motor just below the intake plenum near the firewall.

We noticed the leak goes away when the motor warms to operating temp but comes back once it cools off.

 

“Borrow” a coolant system pressure tester from your local parts store that loans tools (you pay purchase price up front then they refund your $ when you return it). Pressurize the system to the pressure indicated on the radiator cap then wait and watch.

Another potential for leaks, especially on older vehicles that the coolant is old, are freeze plugs. These are placed at various places on the outside of the block (sides, front, back, back or front of heads). They are sacrificial and designed to get pushed out by the expanding ice of the freezing coolant to relieve the pressure and keep the block or head from cracking. Over time they can rust and develop a leak. In the early stages, the leak will seal up with the thermal expansion of the warming engine.

Short term “fix” would be to put Bar’s Leak in the coolant.