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anyone got a twin groove pully for A/C

14235 Views 70 Replies 15 Participants Last post by  tekenaar
BQS4 said:
It seems I have run into a batch of Mantas. I have one parked in the driveway right now (74 Rallye, rust bucket, being stripped for parts) and another waiting for me out in west GA this weeked (another 74 Rallye, again a rust bucket, but, has great parts) and another 75 Manta in east GA I intend looking at this weekend (again, another rust bucket waiting to be stripped)
Still looking for twin pulley A/C crank pulley and right side (Manta/1900), aluminum A/C pump mount . . . :confused:
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Right . . . correct . . . uh, passenger side

RallyBob said:
Otto, if Dave's pulley doesn't pan out I should have one too. No aluminum compressor brackets though, the ones I have are steel.

Would've helped if I'd said right, as in correct or passenger, side . . . Senior Moment . . . :rolleyes:
Right side air pump bracket . . . '68 1.9?

RallyBob said:
Otto, if Dave's pulley doesn't pan out I should have one too. No aluminum compressor brackets though, the ones I have are steel.

Thanks for the twin pulley offers from RallyBob and nobody. Found an extra right side GM compressor bracket, BTW, but not going to work for what I want to do, so I'm not going to just cut it up.

Anyone have a cast iron air pump bracket or two from a '68 1.9 engine . . . and, maybe, an air pump that goes with it?

Two different projects: bracket and pump - modify pump to use in reverse (vacuum) to evacuate my 2.15 SSD crankcase; bracket only - modify bracket for mounting Nippodenso 10P08E compressor (very small, rescued from junk-yard many years ago for use in Opel) for hand-fabricated A/C in '69 Kadett.

Based on ~630 mile round trip to San Antonio last weekend, these old bones don't take too well to long, non-A/C drives in the summer heat down here anymore. A/C is on front burner, as I'll likely take '69 Kadett to OMC . . . if I go. Now you know . . . any of those in anyone's stash somewhere? I'll document and post on one or both projects.
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nobody said:
It seems the guy with the wagon and GT had another wagon previous that had AC. I'm absolutely positive the condensor and pulley are there. I won't be needing either but they come with the parts lot. I'll be picking them and the wagon this weekend. There may be more GT and wagon AC bits yet uncovered on this one.
Thanks. Let me know when and what shipping, etc. would be. Thanks.
Nippodenso 10P08E compressor dimensions

RallyBob said:
One of the ultimatums I had made to myself . . . was . . . I was going to have to make a mounting bracket for it anyway.

Otto, if you have a detailed drawing I could probably fab up an aluminum bracket in a couple of hours for you. Just a thought, and the practice wouldn't hurt me :)

Sounds very intriguing, Bob, thanks for the offer. I'm enclosing a picture of the compressor with all the pertinent mounting dimensions so, if you can do the mockup of the block and crank with twin pulley for bracket dimensions there, all should be good to go. Let me know if you have any questions about compressor pic. Thanks for entertaining this.


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Fort Smith, AR

nobody said:
Otto, do you ever get out to Fort Smith Arkansas?
Not normally, but who knows . . . :rolleyes:
Block face to c/l front (dual) pulley measurement?

How about a measurement from the centerline of the "V" of the front pulley from the dual pulley crank pulley to the machined front face of the block where the timing cover mounts? I get ~110mm estimating from standard single pulley at ~95mm for this dimension . . . close? Need more accurate measurements for some drawings I'm working up. Thanks.
Trial mockup

RallyBob said:
How would you want it configured, as far as the 'clocking' of the compressor? I can see the bolt (size?) for the belt adjustment at the top of the pic...where would that be situated (since I don't know the routing of the compressor lines it would be important). What diameters are the lower mounting tab holes?

Just did a mockup on the Kadett and realized there are serious V-belt drive to lower radiator hose interference issues if pump is mounted on right side of engine. Though I'll have to fab two brackets, much easier to mount alternator on right and compressor on left where alternator normally mounts. Come to think of it, I used the same arrangement on two GTs where I installed A/C . . . don't know what I was thinking.

I'll mount the pump low, pivot axis below pan rail, so that I don't have suction or pressure hose mounting interference issues at the distributor. Not sure yet, but may have to resort to idler pulley for pump belt tensioning. Still'd like to know c/l of front dual drive pulley to block face dimension if you have time. I'll toss together a dimensional drawing of required mounts.
Dual pulley question

nobody said:
Otto, I didn't get a chance to measure it. On the other side tomorrow it's southbound.
Is the alternator/water pump V-belt driven from the rear pulley of dual crank pulley? :confused: Assume so . . . thanks.
Dimensional A/C compressor bracket drawing . . .

RallyBob said:
One of the ultimatums I had made to myself concerning the drive out to the OMC this year was I would only go if my wagon had A/C (my Canadian blood doesn't tolerate heat and especially humidity). That's a moot point now since I don't have the money to go and the wagon is nowhere near completed anyway. But, I was going to use the A/C I stripped from my Nissan Sentra which has a nice, efficient, lightweight compressor that will easily fit the turbo wagon. That said, I was going to have to make a mounting bracket for it anyway.

Otto, if you have a detailed drawing I could probably fab up an aluminum bracket in a couple of hours for you. Just a thought, and the practice wouldn't hurt me :)

Had to rethink the whole thing a bit, as I said, but if the offer is still good, here's a drawing of the driver side compressor bracket. Not drawn to scale (couldn't find a "grid" in Paint!), but all the dimensions listed are accurate. The 2.625" dimension between the back sides of the pivot arms is the most critical as pump arms will mount to it from the rear. Mocked pump up to run off front pulley on driver's side and will have to fab passenger side alternator bracket as well. Up for that one too? :confused:


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Bit of ignition . . . switch? . . . help

nobody said:
You just got me to think about it. Paul has that Pulley in fort Smith now so alot closer anyway. I got an underdrive pulley this way and the dual went that way. Opelers are a good bunch.

Otto, I think the GT could use a bit of ignition help like a relay perhaps. Not that I had a plan on this or anything.
I may be able to help you there, Dave . . . uh, you did mean ignition switch, right? :confused: Send me your snail mail address.
Sanden micro-size compressor . . .

Sportwagon75 said:
Otto - You might want to check out the following thread.
It has some good food for thought. GTJIM in New Zealand sent me one of his home made multi-V pulleys that he fabricated for Opel engines. There are pix of it in the thread. I think he may have more. You may also get some ideas for using the very small Sanden compressor I referenced in the thread. There's even a photo of it with mounting hardware for a SB Chevy. It's also available in twin groove format. It works very well in my little 3-cylinder Geo Metro and all the parts are very small. Just some food for thought.
Checked it out many moons ago and had already copied pics and specs for future reference.

My little Nippodenso unit is very similar to that Sanden unit, size-wise . . . ~1/2" larger diameter is all and with a single V-belt pulley. Bet he didn't get his for $15 though . . . :eek:
5-blade vs. 7-blade WP fan dimensions

oldopelguy said:
One other issue of concern in the Kadett with AC was the fan. The 1.9 motor is so close to the radiator that you can't space it forward to clear the pulley like the Manta and GT, instead they cut away the rear 1/2" of the fan instead to clear the pully. Doing it and keeping it balanced is a real chore if you have to do it to one yourself. Do yourself a favor and start out with a 7-blade one, though, to keep as much fan as you can.

To top it all off, the condenser sits right up against the support brace in the front, so no room for a "normal-sized" electric fan on the front either.
Currently my 1.9 uses a 5-bladed fan which has a measured ~1" frontal blade clearance to radiator's bottom tank lip, most rearward frontal fan obstruction. The 5-bladed WP fan mounts ~3/8" further forward (toward radiator, more crank pulley clearance) than the 7-blade fan, in case you're curious.

My WP fan clearance mockup is based on a 7-blade fan and an 11/16" spacer I had, mounted between the stock WP pulley and 7-blade fan. This results in ~3/16" clearance on both sides of the fan blade's closest obstructions . . . tight, but enough running clearance and I can use the full 360mm diameter of the fan without any blade modifications! :eek:

Rear V-belt will drive the WP and relocated alternator, front V-belt will only drive the A/C compressor on the driver side. WP radiator hose will be routed around the back of and under the alternator to the radiator. GT ARA A/C systems used a cast aluminum piece for lower radiator coolant routing with their twin piston compressor, which I will use to route coolant around passenger side mounted alternator. There's a bit more room to do this in a Kadett than in a GT . . . :)
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Dual groove crank pulley . . .

Paul said:
So that's what this funny looking pulley is for... :confused:
Could you box the pulley up and parcel post it to me? My snail mail address is:

Otto Bartsch
P.O. Box 860608
Plano, TX 75086-0608

I'll send you something for your daughter's car's ignition switch, per Dave's earlier suggestion. ;) Send me your snail mail address so I can get it underway.
Paul said:

Sure thing. My address

Paul Crane
4814 Mount Zion Rd
Greenwood, AR 72936

However, I fly to St Louis at 630am Monday and dont get back until Thursday night. So I might not get in the mail until Friday. Hope that's not a problem.
Not a problem, Paul. Yours is on the way today and should be there by Thursday.

Would you, or anyone else reading this, have an extra 1.9 aluminum alternator bracket and an unmodified stock 7-blade WP fan? I have two fans, but both were pretty severely butchered by POs, so really no good for anything but measuring clearances.

Another thing I'll need (I thought I had another but can't find it) is the cast aluminum coolant duct that was used with ARA A/C systems and mounts between the WP and lower radiator coolant outlet with two hose pieces, see pic. I'll need this to reroute the lower radiator coolant hose around the repositioned alternator on the passenger side.


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Aluminum alternator bracket offsets

RallyBob said:
Otto, don't forget there are at least three different types of aluminum alternator brackets (plus the older cast iron brackets) There's the 'thin' style that is very prone to cracking, then there are the thicker-section pieces, and of those there are two offsets (away from the side of the block, not fore-aft). This fact used to really mess me up swapping stuff out when I'd try a fan belt and it wouldn't fit because of a longer bracket!

Hmmmm, didn't realize that . . . guess I've been lucky. Got any offset measurements, Bob? Been doing some more trial fitting and may be able to get by with modifying 2 stock aluminum alternator brackets if I mount the alternator upside down on the passenger side. Have to do some more detailed measurements, but I'll let everyone know how mock-ups turned out. Back to work . . .
Latest dual pulley update . . .

Received Dave's dual crank pulley in the mail from Paul . . . thanks to both.

Had assumed that dual crank pulley was just a second pulley in front of the standard single crank pulley . . . WRONG! The WP/alternator drive pulley is moved forward by 5mm and the compressor drive pulley is mounted to the rear of it. Thought it was a bit odd that they changed the standard belt path of the single pulley, requiring spacers for both alternator and WP. So, just to save everyone else looking at this some time, let me recap what I've found, at least what's used for "stock" A/C mounting.

When I checked my pictorial parts manual, sure enough, WP and alternator drive spacers were used on both the Kadett and 1900/Manta. They don't show any ARA stuff, BTW, so that was strictly a "dealer select" option. Kadett mounts the GM compressor up high on driver side, much like the GT, while the 1900/Manta mounts it low on the passenger side right next to the oil filter, but they both use the same pulley and WP/alternator spacers according to the parts manual.

This changes all my previously measured mounting locations, so it's back to the drawing board for me. Soon as I have some new measurements, I'll post here. Thanks to all who are providing bits and pieces for this. Hope to arrive at a general installation guide with critical measurements for using a Sanden/Nippodenso 10-piston type compressor, the most commonly used one, for A/C conversion.
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Further research . . .

Some background. Saved a complete dealer's A/C installation instruction for 1900/Manta for '72-'75. This has templates for cutouts and everything. Also has detailed list of parts needed complete with pics of those parts. Don't know why I didn't go there first! :rolleyes:

Here's my quandry . . . the dual crank pulley shown has the WP/alternator driven off the rear pulley and the WP spacer is used between the pulley and the fan blade to clear the front crank pulley (stock belt path is unchanged)! Looks like my original assumptions (added pulley at front of crank pulley, same belt path for WP/alt) were correct after all! :eek:

Figured out where the dual pulley Dave sent was used . . . to drive the 1969 1.9 AIR pump. Thought it was odd that the stock belt path was moved forward and that the pulleys were different size. Anyway, looks like I'm STILL looking for an A/C dual crank pulley . . . P/N 3032075 according to parts book and dealer A/C installation instructions. HELP!!

Bob, Gene, could you verify your dual crank pulleys have both drive pulleys the same size? :confused:
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ARA A/C in that '72 GT?

greensmurf20 said:
a local has a 72GT thats an automatic with air conditioning. the crank pully has the same sized pullys on it. it uses the air conditioning system where the compressor is on the drivers side of the engine if its of any signifficant value of information.
Compressor is a vertical twin piston type on welded steel bracket and mounts slightly above WP level with an idler pulley mounted to the front of the cam 3-bolt cover, right? That's an ARA installation, like the one that WAS in my original '73 GT.
Dual pulley belt path and WP spacer . . .

jlthunder said:

That is very interesting. I have a dual pully on my '72 GT which was from my '74 Manta Luxus. No spacers are present on the alt or waterpump. I don't have A/C and never had a belt issue.

Which pully does your alt & water pump go on, the front or back?

According to my factory "dealer" install instructions for the 1900 series, the WP/alt belt path is unchanged and runs off the rear dual pulley. The spacer for the 7-blade fan is placed between the WP pulley and fan to give fan blade clearance at the dual crank pulley. The spacer is steel and ~7mm thick.
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