C-3, '72 A/C Hose Problem / Question

[Bill Lloyd #33481]

I have a base motor 72 with A/C. The compressor hose system continues to crack between the compressor manifold and the muffler. This point in the aluminum piping seems prone to cracking (weak point). Is there any remedy to this design shortcoming? This is getting expensive.

Thanks,
Bill

[Terry M.]

Re: C-3, '72 A/C Hose Problem / Question

I am not aware (but I don't have AC on my C3) of such a systemic problem, and while we occasionally see a welded tube on judged cars, such a repair is not commonly seen on the judging field.
If more moisture gets into the AC system than the descant can absorb, that moisture will combine with the refrigerant and form hydrochloric acid. That acid will eat the pipes, weaken them, and possibly cause the chronic cracking you are experiencing.

[Jack H.]

NO! Could be 'Bubba'....

Factory original compressor manifold was a SOLID 'chunk' of aluminum with inlet/outlet tubes welded in place. This has LONG been GM discontinued in favor of the replacement design that looks like a set of 'binoculars' (expect a healthy deduction on the judging field for use of these service replacement A/C hose assys) and that's the hose/manifold setup you got/get from GM and Corvette catalog parts houses for a LONG time to replace the factory original A/C compressor inter-connect.

The Catch-22 is when the original design was replaced with the 'binocular' style compresor manifold in production, those cars also got a stamped steel strain relief 'bar' to keep the bolt mounting the manifold to the compressor from over stressing the thin-wall section between the 'binoculars' from cracking....

Bubba mechanics typically broke the factory original 'solid chunk' manifold by grabbing/pulling on the A/C muffler and wound up ordering a GM service replacement manifold/hose assy. Then, they installed the replacement assy WITHOUT the stamped steel strain relief plate surrounding the attaching bolt!!!!

If they also failed to route the A/C hoses through their factory original inner fender hose clamps, BINGO the hoses would vibrate, over-stress the service replacement binocular aluminum manifold attached to the compressor and it would fatigue fracture, down the middle adjacent to the attaching bolt, causing loss of R-12.

This is a 'typical' syndrome of 'bubba' mechanics doing a blind leading the blind repair. Plus, today's Bubba mechanics scrath their head and simply replace the failed service replacement manifold/hose assy with another and the cycle starts anew!!!! IF this is your problem then you have TWO solutions....

(1) Bend over and pay through the nose for a correct/original AC manifold/hose assy. You'll be rewarded with full originality points on the Judging Field....

(2) Go to ANY local scrap yard and find a car 2-3 years later than your Corvette was built that incorporated the 'binocular' style A/C manifold/hose assy from the factory and pirate it for its stamped steel strain relief bar. Install the strain relief stamping and MAKE sure you have the correct/original hose clamp(s) at the inner fender--watch your problems go away!

Amazing what happens when correct designs are implemented as the factory original designers intended vs. 'botch jobs' done by 'experts' who think they know what they're doing....

[Bill Lloyd #33481]

Re: NO! Could be 'Bubba'....

Jack,

Thanks. I have the binocular style hoses. I fear the original were treated as you described. I will search for the stamped steel strain relief bar. This seems to be my problem.

Bill