Is my A/C compressor too fat? [pics]

[Michael F.]

I'm rebuilding the AC on my 71 454 and I'm confused about the front AC compressor mount. With the front brace in place, there's no way the bracket can fit onto the pin. It's like the bottom sump is too big. This compressor came with the car, unmounted. Is it the wrong one?

[Mike G.]

Re: Is my A/C compressor too fat? [pics]

Looks like a standard A6. Will it work if you change the assembly sequence by putting the lower bracket onto the pin BEFORE you bolt them to the compressor flange?

[Michael F.]

Re: Is my A/C compressor too fat? [pics]

I tried that, but there's still too much interference from the sump. It causes the brace to not sit flat on the compressor. I've been reading that there's two sizes of the A6 and the Corvette (and Corvair) used the smaller one. Is there a way to tell which ones which?

[Dale C.]

Re: Is my A/C compressor too fat? [pics]

It looks like my A6 has more space between the buldge and the mounting plate.
IMG_1502.jpg

[Michael F.]

Re: Is my A/C compressor too fat? [pics]

It looks like my A6 has more space between the buldge and the mounting plate.
[ATTACH=CONFIG]41929[/ATTACH]

Thanks for the pic Dale. What car and year did this compressor come out of? Do you have the model #?

After looking at your pic, the compressor I have seems to have a bigger sump. Maybe that the difference in the A6 sizing. Most are 12.6 cubic inches and the Corvettes are 10.8.

[Mike G.]

Re: Is my A/C compressor too fat? [pics]

I just measured the 4 A6's I have and all are the same 1 3/16" clearance from the square mounting flange to the start of the sump bulge. FWIW, the case is 14 7/8" in circumference just aft of the flange. It's unlikely that any are original Corvette/Corvair units.

[Domenic T.]

Re: Is my A/C compressor too fat? [pics]

Michael,
I have been rebuilding A-6 compressors for ages and I haven't noticed a size difference.

The differences in the vette compressors are the pistons (dished) and pulley sizes. your pulley should measure about 5 3/4 inches.

The case differences I have here in the shop are swaged and welded cases (interchangable), yours is swaged which is correct.

The aircraft A-6 is also the same size as the auto.

DOM

[Mike G.]

Re: Is my A/C compressor too fat? [pics]

I wish I could see the other side of your square flange. Do you have the other 2 bolts threaded into the flange?
If the answer is yes, then the next question is whether this is an original or repro bracket. That pivot pin looks too good to be an original bracket.

[Michael F.]

Re: Is my A/C compressor too fat? [pics]

Michael,
I have been rebuilding A-6 compressors for ages and I haven't noticed a size difference.

The differences in the vette compressors are the pistons (dished) and pulley sizes. your pulley should measure about 5 3/4 inches.

The case differences I have here in the shop are swaged and welded cases (interchangable), yours is swaged which is correct.

The aircraft A-6 is also the same size as the auto.

DOM

Good to know. Thanks DOM.

[Michael F.]

Re: Is my A/C compressor too fat? [pics]

I wish I could see the other side of your square flange. Do you have the other 2 bolts threaded into the flange?
If the answer is yes, then the next question is whether this is an original or repro bracket. That pivot pin looks too good to be an original bracket.

Yes, all three bolts were in. I think I need to grind down the bracket some to clear the compressor body. And then install the brace first (with the pin) and then the compressor. Hopefully I can get to all the bolts.

[Michael F.]

Re: Is my A/C compressor too fat? [pics]

Well, it's a success. After grinding the bracket down a little, it fit OK. And attaching the three bolts last wasn't too bad. I had elbow wrenches which helped.
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[Mike G.]

Re: Is my A/C compressor too fat? [pics]

Well, it's a success. After grinding the bracket down a little, it fit OK. And attaching the three bolts last wasn't too bad. I had elbow wrenches which helped.
[ATTACH=CONFIG]41938[/ATTACH][ATTACH=CONFIG]41939[/ATTACH][ATTACH=CONFIG]41940[/ATTACH][ATTACH=CONFIG]41941[/ATTACH]

Good deal! In the Defense Industry, this well-established process is known as "file to fit".

[Dale C.]

Re: Is my A/C compressor too fat? [pics]

IMG_2619.jpgMike
Maybe it's a year thing but my connector mounts on the outboard front of the compressor whereas your picture shows you connector on the oposite, inboard, side. My compressor is a Feb 68 casting.
Dale

IMG_7802.jpg

[Michael F.]

Re: Is my A/C compressor too fat? [pics]

Mike
Maybe it's a year thing but my connector mounts on the outboard front of the compressor whereas your picture shows you connector on the oposite, inboard, side. My compressor is a Feb 68 casting.
Dale

I'm confused about this too. Most rebuilt compressors have the connector on the inboard side. But I've seen a lot of factory ones with the inboard connector.

[Mike G.]

Re: Is my A/C compressor too fat? [pics]

I'm confused about this too. Most rebuilt compressors have the connector on the inboard side. But I've seen a lot of factory ones with the inboard connector.

Midyear A/C cars were delivered with the clutch coil connector positioned on the outboard side, since that's the direction the wiring is routed from. In the trade, this is designated as the "10:00" position.

The large majority of new/rebuilt A6 compressors have the connector positioned at the 2:00 position (viewed from in front of the car). You have to look hard to find one at the correct 10:00 position. And then the pulley is usually too small.

Kind of a shame because removing the clutch plate and pulley is not that difficult with the right tools (Kent Moore/Robinair 10500) and then the coil is easily re-positioned. Does not require disturbing the shaft seal either, so it can be done on the car (hood removal recommended).