1975 L-48, 4 speed with A/C Heater hoses?

[Lynn S.]

The 1975-77 NCRS technical manual and Judging guide page 77, Heater Hoses, reads ... the most common designs have 3 or 4 narrow ribs along their length that is a code to indicate the manufacturer. These ribs are narrower than those on current service replacements. A/C cars have molded bends at the heater core and intake manifold end. On Non-A/C cars without an expansion tank, ...
Checking with several vendors who state in their description "reproduction quality or same as original" for the correct hose replacement, I am repeatedly told that '68 - '82 cars with A/C in their experience had smooth hoses due to the additional manufacturing process to mold in the bends at each end. Their experience had the ribbed hoses on Non-A/C cars '68 - '82.

I cannot find ribbed hoses with molded ends.

Please advise. Thanks

[Edward J.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Lynn, There does not seem to be any Corvette venders interested in making these hoses, about 10 years ago when I restored my 72 and I was looking myself for the hoses. judging the hoses it only 1 point deduct.

[Tom R.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Lynn

We are in the midst of the 75-77 revision and, ironically in the cooling system section. I'm attaching a draft of the revision for heater hoses and we are in process of confirming part numbers and configuration. You'll find that A/C were molded and included, perhaps not ribs but grooves. Also, introduced in 74 is the water-shut off valve but we find conflicts with its use in 75, whether included with A/C or non A/C applications. After 75, all years included the water shut-off valve and the same hoses were used. So take a look at this. Perhaps you can help us "tweak" the details as configured in 75.

1975-77 _heater hoses_23Oct20.pdf

[Larry M.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Closest I have found are from DR REBUILD. Assuming he opens his store back up, you should probably get these for your car.

Larry

[Edward J.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Larry years ago Doc had one NOS 3/4 hose, @120.00 I believe.i ended up buying the molded hoses from him. No groves or or codes stamped on them. I like some of the Doc parts, I am to waiting to place an order with him, last I heard it was going to be beginning of next year.

[Lynn S.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Thanks Larry for your input and advice. Mine is not a Survivor car. Just one I am trying to restore as correctly as possible.

[Lynn S.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Thanks for your help and the attachment. My car was one of the proverbial basket case cars. Not a fully assembled survivor. So I'm just trying to restore it as correctly as possible. Hope to see you in Lakeland next February.

[Lynn S.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Thanks again Larry for your reply.

[Lynn S.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Ed, thanks for your reply. I will probably go your same route and take the hit on originality.

[Jeffrey S.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

The 1975-77 NCRS technical manual and Judging guide page 77, Heater Hoses, reads ... the most common designs have 3 or 4 narrow ribs along their length that is a code to indicate the manufacturer. These ribs are narrower than those on current service replacements. A/C cars have molded bends at the heater core and intake manifold end. On Non-A/C cars without an expansion tank, ...
Checking with several vendors who state in their description "reproduction quality or same as original" for the correct hose replacement, I am repeatedly told that '68 - '82 cars with A/C in their experience had smooth hoses due to the additional manufacturing process to mold in the bends at each end. Their experience had the ribbed hoses on Non-A/C cars '68 - '82.

I cannot find ribbed hoses with molded ends.

Please advise. Thanks

Lynn,
Attached are hoses with the molded ends and grooves/ribs. I purchased these from the vendor in the second photo at Carlisle.
Jeff

[Edward J.]

[Lynn S.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Thank you very much Mr Salzburg for the info on the hoses. I will be calling them Monday morning. Wish me luck.
Lynnf

[Jeffrey S.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Jeff I’ve seen that vender in Carlisle, that’s the first time I have seen a hose with grooves do you remember if both hoses has the grooves or was it just the 3/4 hose? Thanks Ed, hope there still in business.

Both hoses had the same grooves. They also had the GM logo- lacquer thinner works great!
Jeff

[Jeffrey S.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

Thank you very much Mr Salzburg for the info on the hoses. I will be calling them Monday morning. Wish me luck.
Lynnf

OK- good luck!
Jeff

[Joe L.]

Re: 1975 L-48, 4 speed with A/C Heater hoses?

All------


The number of ribs or grooves on the hoses was a code which denoted the hose manufacturer. I don't know that they were required if the manufacturer was otherwise identified by a code printed on the hose.