Leaking Testarossa Heater Matrix Hoses - Help?

Main heater supply hose from engine runs up central frame tube with AC hoses. It terminates inside car above pass feet. Return hose goes same way. No heater hoses on left side. It may be a leak from left radiator or hoses running down left rocker to front.

 

No. The bottom is pretty solid. The entire heater assembly is in the interior under the dash. There is a drain hose for AC condensate under the car. Look there. The hoses enter a frame tube between the fuel tanks and exit that tube below the console very near the shifter.

 

Replacing the heater hoses running up the center tunnel. Attach new hoses to old at engine, Silicone lube new hoses. Pull old old hose out from pass foot well.

 

Another possibility and its way better than a leaky heater running out the condensate drain hose.

The frame tube the heater hoses run through isn't sealed. It is an upside down "U" with only the riveted on belly panel covering it. It is possible a leaking hose could find another escape route. If that is the case it should run out the back where the hoses enter, between the fuel tanks. If you elevate the front and pressure test the system you will know. The hoses are not hard to change. The heater assembly is decidedly not.

 

Conventional hose clamps. I see no need for special expensive hose, The hose in it has lasted well over 30 years. Does it really need 60 year hose? Don't know about you but I won't be around that long.

I do not recall size but I'd get a roll of it. The tube it runs up is pretty crowded with other hoses so I'd attach new to old and use the old hose to pull the new in.

 

when I remember right the hoses are 20 mm - but not sure

 

The fittings in the engine bay for the long hoses are 16mm diameter (not including the sealing bulge) -- i.e., the long hoses are "16 mm ID" hoses (although the free diameter of a hose is usually a little smaller than the "nominal" diameter). It gets a little weird up by the hot water valve (which has 20mm diameter fittings) so they use an expander fitting, 124030, and a short piece of 20mm hose (see TAV 57 in the TR SPC) to connect one long hose to the hot water valve (and then a 20mm hose from the other hot water valve fitting over to the HVAC unit fitting). The other 16mm long hose connects directly to a 16mm fitting on the HVAC unit (i.e., the two fittings for the hot coolant hoses on the HVAC unit are two different sizes).

Word of warning -- don't not get the two long hoses swapped around. The coolant flow direction thru the hot water valve has to match the arrow on the hot water valve -- otherwise, the hot water valve can't keep itself closed so you will get heat all the time.

 

sorry, thaught all are 20 mm. long time ago I was working at the heating

 

I installed a manual valve also at the electric water valve. It defaults to open. It would rarely open and heat the cabin in summer.

 

Find somebody with long, skinny, flexible hands and arms that likes working in upside down positions.