Interior GT400 2+2

Heater components


I received the Aeroquip 2556-8 hose from Murdock Industrial today and it could not be better! It is exactly what I was looking for to duplicate this 1968 OEM heater hose for Lamborghini GT 400 2+2.....fits the heater core, diaphragm valve, engine spigots......the OEM "P" clamps that fasten the hose to the wheel well fit perfect....the LH spiral is correct, the fabric wrap look is perfect.  Probably best heater hose match for any Touring/Marazzi  body Lamborghini.   Thanks to Zac at TomYang's Ferrari forum.

Note - The hose clamps to fasten this heater hose at water pump and water tube are a very early Serratub 1.
A different brand and style hose clamp are used on the heater hose at interior locations (valve and heater core).

Blower Motor and Heater Core Removal Procedure GT400 2+2
1) Remove the floor carpeting and heater vent console side panels from both sides.
2) Cover the seats and the center console.
3) Remove the center dash gage/switch panel. As you remove, label and disconnect each gang plug.
4)  Push the wires and plugs up in the cowl area above the heater to allow clearance for continuing work.
5)  Remove the tape or clamps that holds each defroster nozzle flexible paper ducting to the heater box.
6) Slide each flexible hose to provide clearance to remove fan box.
7) Remove the two 5mm (8 mm hex) bolts at either side of the blower box.
8) Pry the blower box away from the heater core box with a large screwdriver. Box flange probably firmly attached with foam gasket material that will come apart.
9) Pull the blower box to the right and tilt it forward as you bring it out from under the dash. It has a pair of black wires, one going to a ground connection to the right (and thus no much of a problem) and another wire you have already disconected going to wire hareness.  Pull the blower box out of the car.
10) Disconnect the right side heater hose from the water pump where it connects to the engine at the right lower side near the lower radiator hose. Make sure that hose is free to slide to the rear a few inches. Be prepared to catch coolant at water pump.
11) Back in the passenger compartment, pull the upper right corner of the heater core to the rear, pulling a few inches of heater hose with it at the top right. Disconnect the heater hose, but be aware that the core is full of coolant so any tilting will result in a spill. If access to that hose is all that is required, then removal is complete.
12) Pull the lower left hand corner of the core to the rear far enough so the lower left heater hose if clear of its notch in the core box.
13) Slide the heater core to the left far enough so that you can position a suitable container below it to catch a few cups of coolant.
14) Disconnect the lower left heater hose and catch the coolant flowing out of the core. The heater core may now be removed.
Reassembly is the reverse of disassembly.

Islero Folks (and to some extent 350/400GT folks) by Alan Watkins
I decided to replace my heater hoses since it was obvious that some sections are quite old. Since one of the connections is behind the heater core which rests in a box sunk into the firewall, and which is behind the blower box, you have to do some interesting disassembly to access that end of the hose.
I thought you might find the procedure for doing this interesting (or even useful). After I did this I wondered why the factory didn't just put a 2" longer spigot on the heater core that would protrude through the firewall, thus obviating all this work just to replace a hose. This would also provide a better grommet closure since a grommet around a rubber hose is a pretty dumb idea. I will probably do this (actually have my radiator guy do it).
Islero instructions
Blower Motor and Heater Core Removal Procedure
1) Remove the kick panels from both sides of the transmission tunnel.
2) Remove the shift knob and the center console.
3) Remove the passenger side under-dash kick plate.
4) Remove the center dash as you remove to the rear or disconnect each switch.
5) From underneath the dash, remove the two small nuts that hold each defroster nozzle to the dash.
6) Slide each defroster nozzle out of its flexible hose, and remove the flexible hose. This provides clearance for the next step.
7) From underneath the dash, push the dash recess panel up and away from the dash. This will provide access for step 8 below.
8) Remove the two 5mm (8 mm hex) bolts at either side of the blower box.
9) Remove the two 5mm (8mm Hex) bolts located along the top of the blower box. The one on the right is reasonably easy to access through the opening in the top of the dash provided by step 6. The best tool is a ¼” drive 8mm socket on a 4” extension with a ratchet. The one on the left requires working blind from beneath the steering wheel, and may require use of a small 8mm open end wrench to get started. Probably the removal can be finished with the ratchet and socket.
10) Remove the three nuts that attach the dashboard to the frame: one on each side of the dash visible from the footwell looking up, and one in the center.
When removing the outside two nuts also remove the Phillips screw that attaches the corner of the dash to the body.
11) At this point the dash is detached, and you should be able to slid it to the rear and up, providing clearance above the blower box. But be careful of wiring, etc, as you move the dash. 12) Pry the blower box away from the heater core box with a large screwdriver. Mine was firmly attached with foam gasket material that came apart.
13) While lifting up on the dash, pull the heater box to the right and tilt is forward as you bring it out from under the dash. It has a pair of wires, one going to a ground connection to its right (and thus no much of a problem) and another (blue-white) wire taped to a wiring harness to the upper left. As soon as you have access to that tape, cut it to release the wire. Pull the blower box down far enough so that you have access to the heater core. If you are not going to work any further on the blower box or blower, skip to step 17.
14) Remove the four 8mm hex bolts on the bottom of the blower box. These are in fact nuts on studs, but in my case the studs unscrewed first. The studs are flanged and rest inside rubber grommets. When all four are released, you can slide the blower motor out of the box by lightly grasping the fan.
15) When you have access to the wire terminal on the fan motor, pull both leads off. Remembering which is which is not critical because at re-installation you can attach them both ways to confirm correct fan rotation (that which blows air out of the four outlets.
16) The wires can be removed through the grommet in the side of the blower box, one at a time. This leaves the blower box free in case any work is to be done on it (such as replacement with a modern, powerful and quite fan).
17) Disconnect the right side heater hose from the water pump where it connects to the engine at the right lower side near the lower radiator hose. Make sure that hose is free to slide to the rear a few inches.
18) Back in the passenger compartment, pull the upper right corner of the heater core to the rear, pulling a few inches of heater hose with it at the top right. Disconnect the heater hose, but be aware that the core is full of coolant so any tilting will result in a spill. If access to that hose is all that is required, the removal is complete.
19) Pull the lower left hand corner of the core to the rear far enough so the lower left heater hose if clear of its notch in the core box.
20) Slide the heater core to the left far enough so that you can position a suitable container below it to catch a few cups of coolant.
21) Disconnect the lower left heater hose and catch the coolant flowing out of the core. The heater core may now be removed.
Reassembly is the reverse of disassembly.