20R to 22R swap - coolant hose routing?

Discussion in 'Engine/Drivetrain' started by Henry, Feb 21, 2021.

  1. Henry

    Henry Enthusiast

    Joined:
    May 18, 2013
    Messages:
    257
    Likes Received:
    14
    Location:
    Washington State
    Just pulled the 20R from my '77, and I'm about to swap in an early 22R. I had a question in regards to how to properly route the coolant lines.

    The drivers side has a connection on the side of the block, but the setup on my 20R had the heater hose connect to the connection on the radiator.

    1. Do I just purchase a block off plate for this connection, and run it directly to the radiator like my old setup? Or do I cap off the radiator connection, and run it directly to the connection in the photo?

    [​IMG]

    The passenger side has me confused. There is the connection on the front cover similar to the drivers side. There is also a connection under the intake manifold, and one on the side of the head (metal connection not installed in photo).

    [​IMG]
    [​IMG]

    2. From what I've read, there is a benefit in keeping the coolant flowing through the intake manifold. So how should I route the coolant lines to retain this, and connect it to the heater?

    heater hose --> front cover
    Under intake manifold --> connection in between intake runners
     
  2. jetas

    jetas Grand Toyotaholic

    Joined:
    Mar 26, 2009
    Messages:
    6,655
    Likes Received:
    1,091
    Location:
    Oxnard, CA
    Truck:
    72.5 Hilux
    On mine the driver side behind the WP is blocked off and i have the heater hoses running from the port under the intake and behind the passenger side of the WP.

    hope this diagram helps a little

    [​IMG]
     
  3. Henry

    Henry Enthusiast

    Joined:
    May 18, 2013
    Messages:
    257
    Likes Received:
    14
    Location:
    Washington State
    Thanks for posting that. I'm still a little confused how I would route my own setup, but this gives me a better idea on what to do.

    Let me know if this make sense.

    Drivers Side:
    I have a block off plate that I could install, and just route the heater hose directly to the radiator. This is how the 20R was routed as it did not have the hose on the drivers side timing cover plate.

    Passenger Side:

    I have 4 connections. (1) Pass heater hose, (2) Behind Timing Cover Plate, (3) Under manifold, (4) 22R Head

    Looking at the direction the coolant flows, does it make sense to connect (1) & (4) together and connect (2) & (3)?
     

Share This Page