620 Air Conditioning

[SWFL]

Apparently the 620 never came with factory A/C, which was common for Hondas from that era and even the 1980s. I know with the 1983-1987 Civics and CRXs that Honda made an A/C kit that you could buy or the dealers would install. Those Honda models used a wide duct that went between the heater core/vent box and the HVAC fan box. The A/C kit had a big evaporator box that would fit in the space that the duct was at, and connect the fan box to the heater core/vent box. I've only seen a wide under dash unit made by Custom Aire from San Antonito TX for the 620. Does anyone know of a cleaner install option and in general how rare period A/C parts are for the 620? I'm not too worried about the stuff in the engine compartment, just the under dash stuff. I'd only want to run a small semi modern compressor like a Sanden TR-70.  

[datzenmike]

The '79 did. The York compressor mounted to the fuel pump area and an electric fuel pump was used similar to the 720.

 

Earlier 620s could have a dealer installed kit.

[Stoffregen Motorsports]

How about a modern aftermarket unit. I have been using the kits from Vintage Air, but there are other systems out there. The units from https://restomodair.com/air-conditioning-systems/  are very nice.

 

If you have some fab skills, put the vents and controls in the dash instead of under it.

[Thomas Perkins]

Forgot what I was going to say.just kidding...

.

 

Edited December 24, 2022 by Thomas Perkins

[yenpit]

As datzenmike states, the 1979 620 did (I thought 78-79.....??) have a factory option of a factory AC system & the earlier 620's could have had a USA made dealer installed system.  These dealer installed "kits" were great for their time, but no comparison to the modern day (I'll say mid 1980's-newer) systems, like your mentioned Honda stuff, whether factory or something like Vintage Air etc.  You will not find a new AC kit for any old Datsun, unless you run across an NOS dealer kit from way back in the day!

 

I do have a dealer installed 620 underdash unit with the long air plenum, but I bought it with the plenum broken in half.  The plenums were "real plastic" (unlike your Honda plastics which were polypropylene plastic (PP), so you CAN epoxy, fiberglass etc to repair...........epoxy's will stick with proper prep!  This underdash unit includes the fan blower assembly, which hangs under the passenger side.  It would need a total resto.  PM me if interested!

 

As stoffregen mentions, if you have an open mind & can fab stuff, a new system like Vinatge Air etc can be fitted, but other than the few here that have done it, you would be on your own for fitting the under/behind dash unit!  Everything else under the hood was universal fit parts anyway in the dealer installed kits, so same applies today................other than fab'ing a compressor bracket!

 

What year 620 do you have & what engine...........L16 L18 or L20B?  All of the L16 L18 dealer installed AC compressor brackets were simply flat stock steel welded together to create a bracket to mount, so any good fab guy can make one to suit a later model Sanden (that's what we use!).  I believe all of these dealer installed kits mounted on the forward lower left...............datzenmike says the factory optional 1979 620 L20B had the compressor mounted forward UPPER right side (like most of the 240Z's).  I have a 1980 720 L20B (last year L20B, first year 720 body style) FACTORY cast iron compressor bracket, mounted on the forward lower left of the block (sorry, not for sale), but that would mean it is kinda rare, cuz 1980 720 only, plus with optional factory air!  I wonder if the 1981-1983 720 NAPZ Z20 or Z22's had this same cast iron bracket??  Maybe even the later Z24, but that block was re-tooled to stroke the NAPZ, so the compressor bracket MIGHT have changed..........??

 

I miss my Civics...........built three 1989 Si's, a 1989 DX hatch & daily drove a FWD Wagon & two RT4WD Wagon's!  Ahhhhh the memories! 😎

[SWFL]

3 hours ago, datzenmike said:

The '79 did. The York compressor mounted to the fuel pump area and an electric fuel pump was used similar to the 720.

 

Earlier 620s could have a dealer installed kit.

How did the factory do the dash vents for the A/C? As I mentioned the 84-87 Civics shared the existing duct work, so the cold air came out of all the vents. Water cooled VW's from that era used a separate duct system for fresh air only vents and then ones for heat/cold. Do you know if the factory evaporator is all aluminum, or copper tube, aluminum fin with sheet metal brackets? Was the factory condenser all aluminum or the copper tube type? Electric fan for the condenser?

 

York compressor, that's an abomination I luckily haven't had to deal with in a very long time. Early water cooled VW's had those heavy POS's. I used remove them and install the later Sanden SD-502s in their place. Saved about 100 lbs and 10 hp by doing that. The square Yorks are basically mini engines, without a cylinder head. Very heavy due to the crankshaft and connecting rods. IIRC the reed valve "head" on those were either thick steel or cast iron.     

[Stoffregen Motorsports]

I would avoid a York compressor at all costs. They're great for converting into air compressors for on board air, but much better A/C compressors are available these days.

[datzenmike]

The AC kits were always mounted below the distributor.

 

Chrysler used big compressors too...

 

 

 

[SWFL]

1 hour ago, yenpit said:

As datzenmike states, the 1979 620 did (I thought 78-79.....??) have a factory option of a factory AC system & the earlier 620's could have had a USA made dealer installed system.  These dealer installed "kits" were great for their time, but no comparison to the modern day (I'll say mid 1980's-newer) systems, like your mentioned Honda stuff, whether factory or something like Vintage Air etc.  You will not find a new AC kit for any old Datsun, unless you run across an NOS dealer kit from way back in the day!

 

I do have a dealer installed 620 underdash unit with the long air plenum, but I bought it with the plenum broken in half.  The plenums were "real plastic" (unlike your Honda plastics which were polypropylene plastic (PP), so you CAN epoxy, fiberglass etc to repair...........epoxy's will stick with proper prep!  This underdash unit includes the fan blower assembly, which hangs under the passenger side.  It would need a total resto.  PM me if interested!

 

As stoffregen mentions, if you have an open mind & can fab stuff, a new system like Vinatge Air etc can be fitted, but other than the few here that have done it, you would be on your own for fitting the under/behind dash unit!  Everything else under the hood was universal fit parts anyway in the dealer installed kits, so same applies today................other than fab'ing a compressor bracket!

 

What year 620 do you have & what engine...........L16 L18 or L20B?  All of the L16 L18 dealer installed AC compressor brackets were simply flat stock steel welded together to create a bracket to mount, so any good fab guy can make one to suit a later model Sanden (that's what we use!).  I believe all of these dealer installed kits mounted on the forward lower left...............datzenmike says the factory optional 1979 620 L20B had the compressor mounted forward UPPER right side (like most of the 240Z's).  I have a 1980 720 L20B (last year L20B, first year 720 body style) FACTORY cast iron compressor bracket, mounted on the forward lower left of the block (sorry, not for sale), but that would mean it is kinda rare, cuz 1980 720 only, plus with optional factory air!  I wonder if the 1981-1983 720 NAPZ Z20 or Z22's had this same cast iron bracket??  Maybe even the later Z24, but that block was re-tooled to stroke the NAPZ, so the compressor bracket MIGHT have changed..........??

 

I miss my Civics...........built three 1989 Si's, a 1989 DX hatch & daily drove a FWD Wagon & two RT4WD Wagon's!  Ahhhhh the memories! 😎

Looking at the pics of one on the bench, I can see it's a stand alone system, not connected to the dash vents at all, and that's why it needs it's own blower fan. 

 

The engine compartment stuff isn't a worry. I can fab whatever mounts I need.

 

I'm looking at getting a 1978 620 with L20B. Eventually I'm going to look at a 1.4 or 1.5 ( high fuel mileage experiment ) and for a work truck, the Z24 ( every time I see that it makes me think of GM ) engine.

 

I kinda got out of Hondas when I moved to FL, but later on picked up some project CRXs ( one is an '88 HF, the rest 1st gens ) and drove a cheap beater 1985 Civic sedan for a few years. I'm thinking of selling most of my impactable cars and just have 2 mini trucks and some scooters.  

[SWFL]

1 hour ago, datzenmike said:

The AC kits were always mounted below the distributor.

 

Chrysler used big compressors too...

 

 

 

Is that the Harley Davidson of A/C compressors? Looks heavy and slow. Reminds me of the Keihin CN-150L used on 80s Hondas 4 pistons like a +, but at least made of aluminum. Still too bulky and heavy.

[yenpit]

22 hours ago, SWFL said:

Looking at the pics of one on the bench, I can see it's a stand alone system, not connected to the dash vents at all, and that's why it needs it's own blower fan. 

 

The engine compartment stuff isn't a worry. I can fab whatever mounts I need.

 

I'm looking at getting a 1978 620 with L20B. Eventually I'm going to look at a 1.4 or 1.5 ( high fuel mileage experiment ) and for a work truck, the Z24 ( every time I see that it makes me think of GM ) engine.

 

I kinda got out of Hondas when I moved to FL, but later on picked up some project CRXs ( one is an '88 HF, the rest 1st gens ) and drove a cheap beater 1985 Civic sedan for a few years. I'm thinking of selling most of my impactable cars and just have 2 mini trucks and some scooters.  

 

Correct, a stand alone AC system.  The Z car got factory optional AC around 1975, all behind the dash, sharing the fresh air/heater venting etc.  I'll get you some pics!

 

I will ALWAYS fall back on an 88-91 Civic, if necessary!  There is an older lady here in Arvada, with a red 89-91 Civic Si hatch..............near mint!  Yes, I gave her my card to put in her glovebox, if she EVER decided to sell it! 😎