No Heat after engine swap

[F1rick]

Hi Everybody, I have a 02 QX4 and I just put in a motor from a 01 Pathfinder (4x2). The swap went well except I'm not getting any heat. The bottom hose going into the firewall is hot and the one on top that turns and runs across the vehicle and down to the head on the drivers side of the car is cold.

It looks like no coolant is passing through heater core. I didn't notice any heater control valve that would essentially block the passage going to the core but this car has the automatic climate control so maybe it's regulated by another device.

The heat was working prior to the swap so I wonder if it's just air stuck in the system. I didn't take the cap off of the bleed pipe at the back of the motor (rookie move) but the pipe is totally cold so I'm thinking something is blocking the flow.

1 more thing. The pathfinder had 4 vacuum lines at the front by the air box and the qx only had 2.

Any ideas would be fantastic and thanks in advance!

Rick
Bay Area

[centralcoaster33]

Well, when I redid my coolant system, including heater core stuff, I hosed out my heater core. Basically I unplugged the two hoses at the firewall and connected one to my garden hose. It blew some odd looking chunks out of there.

While putting it all back together, I filled in coolant/ water wherever I could (not just into the radiator), then connected the pipes. After all of that, I went ahead and bled the air out of the system. My bleeder is sheered off, so I had to do it on a slope and burp it through the radiator.

For you, I recommend flushing out the core. This will verify that you have flow through there anyway. Then I recommend bleeding out the air.

Your vacuum lines are a separate issue. I'd look to the FSM for both engines and see what they were supposed to do. I think you could put in a wye (Y) or tee (T) and run two hoses to one as needed.

[F1rick]

Thanks for the quick response and advice!

Rick