C1 (1958) Heater Copper 90 Degree Elbow

[Justin B.]

The ends of the 90 degree copper elbow are different diameters. Can anyone tell me which diameter goes where? Thanks!

[Richard M.]

Re: C1 (1958) Heater Copper 90 Degree Elbow

5/8" end to a short hose to the heater core, 3/4" end to the 3/4" hose to the water pump. This hose goes through the firewall into the elbow with the clamp inside the firewall. There should be a grommet for the 3/4" hose in the firewall, but reproduction ribbed hoses are too large wall thickness so you may not be able to use the grommet.

[Dan D.]

Re: C1 (1958) Heater Copper 90 Degree Elbow

5/8" end to a short hose to the heater core, 3/4" end to the 3/4" hose to the water pump. This hose goes through the firewall into the elbow with the clamp inside the firewall. There should be a grommet for the 3/4" hose in the firewall, but reproduction ribbed hoses are too large wall thickness so you may not be able to use the grommet.

Affirmative with the hose wall thickness and not fitting through the grommet. But all I did is remove some of the rubber from the grommet ID. Used a grinding bit in an electric drill - did the trick. Did not touch the fiberglass. The hose OD is not a lot larger. It does not take much to make it fit. -Dan-

[Richard M.]

Re: C1 (1958) Heater Copper 90 Degree Elbow

Affirmative with the hose wall thickness and not fitting through the grommet. But all I did is remove some of the rubber from the grommet ID. Used a grinding bit in an electric drill - did the trick. Did not touch the fiberglass. The hose OD is not a lot larger. It does not take much to make it fit. -Dan-

Dan, I was thinking of doing that to my grommet to but my ribbed (no GM stencil type)hoses from CC fit tightly through the hole in the firewall. I don't think it'd work for this one.

Rich