I haven't seen any writeups on MUD about using a Sanden compressor for on-board air, so I thought I would post this one up. I have this build documented on the Rising Sun board originally here:
Brahma On-Board Air
I've never liked going to the gas station to pay for compressed air to fill up my tires after a run. I also don't like inconveniencing others by asking for their air/CO2. I don't like the small 12V compressors because they're noisy, don't have high CFM, don't have a great duty cycle, and the better ones are pretty expensive. And you have to store them someplace when you're not using them.
I don't like CO2 because you have to continually get the bottle filled (repeated expenditure of $$), it takes up a lot of space, and you could forget about topping it off before a trip and run out after filling only 1/2 of your tires. It's not an "endless" supply.
I don't like Yorks because the typical York mount makes you move the alternator down to where the smog pump bracket is. I don't like the idea that my alternator could be submerged in a water crossing while my air compressor, which is not a necessary accessory, is happily dry at the top of the engine bay. I also wanted to try something different that I had heard about from former TLCA President Red Fox (who is also a local club member of mine) as well as from a couple others.
Hence, the Sanden compressor. Found as an A/C compressor in some Fords, Volvos and possibly other vehicles, it has a slightly lower CFM as compared to Yorks, is tubular in shape which saves space, and the only "drawback" is that you have to add oil because it's designed to be lubricated by refrigerant like an Aisin compressor. But there's a port on the top that allows you to do that, so it just becomes part of pm.
The Sanden SD-510 is what I'm starting with, just because that happened to be what Neil Quigley gave me. The SD-508 I think is more commonly found in junkyards and is reputable for this service. The SD508 is a 5 piston compressor which can supposedly put out 9 cfm and 300 psi. I think the SD510 might do slightly more cfm. It's also a 5-piston compressor. The SD-508 has 8 cu. in. displacement, and the SD-510 has 10 cu. in. displacement. I did a quick calc and at 800 rpm the SD-510 should put out about 4.6 cfm with no backpressure. At 2000 rpm it should put out about 11.6 cfm with no backpressure.
Here are some links to websites that reference the Sanden compressor, one of which came from rusty_tlc on MUD:
Grungles Homepage
On-Board-Air Using a Sanden Compressor - Jeepaholics Anonymous
This is the mockup I did when I was in the middle of my power steering conversion. Since I am not running a smog pump, I used the smog pump bracket and tensioner as the foundation of my installation. The tensioner needs to be bent slightly to align with the mounting ears on the Sanden compressor, and the mounting bracket needs no modifications at all.
Now, the smog pump bracket is designed to fit 8mm bolts. The Sanden pump is designed to mount using 10mm bolts. So I went to McMaster-Carr and ordered a few sleeve bearings to make up the difference:
The mounting ears on the Sanden also don't exactly line up with the ears on the smog pump bracket, but a simple spacer from Ace Hardware (3/8" ID, 3/4" OD, 3/8" thick) will make up the difference:
Here's before/after shots of the sleeve bearings going into the mounting ears:
When the compressor is mounted, it's a little close to the stock exhaust manifold, but some heat shields should be able to fix that no problem.
This picture shows the wrap of the belt around the OBA compressor pulley. I have a JT Outfitters bracket holding my Saginaw power steering pump, and I'm using a pulley off of a Volvo 240, due to the wide belt it can accommodate like stock Toyota. This picture still has my old pulley with narrow belt shown.
This picture shows the front mounting bolt on the bottom. It's an M8x35 I believe, and it was just a hair too long so I added a second washer at the head end of the bolt to bring it back away from the pulley just a touch:
This picture shows the rear mounting bolt on the bottom. It's an M8x40 I believe, with the 3/8" long spacer to make up the distance between the ears on the compressor and the ears on the smog pump bracket:
A couple more views:
I'm using a Trollhole replica small courtesy light switch installed in the previously plugged hole in the dash to switch this thing on and off. By the way, in earlier FJ40s this little knob is installed on the right side of the pocket (glove box). My FJ40 has no holes in the dash to the right of the pocket, but I'm able to make use of other holes that are already existing.
The most difficult part about this installation, which also contributed a lot to the overall cost, was the unique connections on the Sanden compressors. The suction side is a 5/8" 45 degree SAE flare. The discharge is a 1/2" 45 degree SAE flare. As an aside, -AN flare fittings are 37 degrees and are not compatible with SAE flare. You can find fittings for SAE flare at your local Ace Hardware, but the only female fittings available are tube nuts. So I would have to get hard tube, flare the ends, and make some adapters if I want to go to any other type of fitting, like to barbs or NPT. Luckily I found some pre-fabbed swivels that helped me get to my NPT connections that I needed so I didn't have to fab up anything myself.
For the air connections, you can commonly find 3/8" and 1/4". I decided to go with ¼” because it seems to be more common. There are also different types of end connections, and I went with I/M as it’s supposedly the most common.
Parts from Ace:
Upper left: Quick-coupler: $4.99
Upper middle: Quick-coupler plug: $1.99
Upper right: Air chuck: $2.99 - Returned this to get one with a clip.
Middle left: 150 psi relief valve: $10.29
Middle: 5/8" SAE flare to 1/2" MNPT 90 degree elbow: $8.49 - for the suction side.
Middle right: 1/2" SAE flare swivel: $9.99 - basically two 1/2" flare nuts with a short piece of tube in the middle, pre-fabbed for the discharge side.
Bottom left: 5/8" SAE flare swivel: $9.99 - for the suction side.
Bottom middle: 1/2" SAE flare to 3/8" FNPT: $4.29 - I can get a Viair 3/8" hose and thread it right into this connection on the discharge side. - Returned this because I needed an elbow - not enough room.
Bottom right: 200 psi pressure gauge: $7.99
More Parts:
Air Hose (50 ft PVC) from Lowe's: $14.02
Manifold from Amazon: $24.02 after shipping
Filter/Coalescer from Amazon: $79.49 after shipping vs. $115 for the one on Kilby's site. This one is made by Interstate Pneumatics, has a metal bowl, and is rated to 300F.
Inlet Filter from Amazon: $30.15 after shipping vs. $28 for the one on Kilby's site. This is the same manufacturer (Solberg) as the one on Kilby's site and I'm assuming it's the same model. It has the same thread connection and is rated for 12 scfm. Heck, the one on Kilby's site may be the one rated to 10 scfm, so if that were to be the case this would be an upgrade. The next largest one is rated to 20 scfm and has a 3/4" NPT connection, which I didn't want. Hopefully this will work.
Air Chuck w/clip from Amazon: $10.37 after shipping
2 x 1/2" FNPT to 5/8" hose barb adapters from McMaster-Carr: $7.52 - this hose barb size is hard to find, but it's what I wanted because I don't want the hose to collapse. Maybe it will anyway and I'll have to redo the suction stuff.
3/8” Viair leader hose with integrated check valve (24” long) + 90-120 psi Viair sealed pressure switch from 4WheelParts: $50.61
30A relay and 2’ of 5/8” ID hose from O’Reilly: $8.08
From Ace:
1/2" flare to 3/8" MNPT 90 degree elbow: $4.49
3/8" coupling for above because they didn't have the above in FNPT: $4.29
Another quick coupler/plug set: $7.49
A couple hose clamps: $2.58
Some sheet metal for mounting the inlet filter: $6.29
3 x 1/4" NPT hex head plugs
3/8" x 1/4" reducing coupling
3/8" short nipple
2 x 3/8" 90 degree elbows
2 x 3/8" x 3" nipples
3/8" x 1 1/2" nipple
1/4" short nipple
1/4" x 1/8" reducing coupling
Total: $361.89, not including the compressor. So it’s pushing $400. Not really any way around it.
More expensive than a couple Viair 12V compressors, but I don’t want a Viair 12V compressor.
I'll need to find the receipt for the belt, sleeve bearings, compressor oil and teflon tape I had to buy, and the compressor was donated for the project but can be had anywhere from $30-$50 at a junkyard.
Here’s pictures of the assembly of the fittings on the compressor.
On the inlet, I have my 5/8" SAE-5/8" SAE swivel fitting, 5/8" SAE-1/2" MNPT 90 degree elbow, and 1/2" FNPT-5/8" barb all connected and ready to go.
On the outlet, I have my 1/2" SAE-1/2" SAE swivel fitting, 1/2" SAE-3/8" MNPT 90 degree elbow, 3/8"-3/8" coupling, and 3/8" Viair leader hose with integrated check valve all connected and ready to go (NOTE THAT THE CHECK VALVE IS BACKWARDS IN THIS PHOTO):
Brahma On-Board Air
I've never liked going to the gas station to pay for compressed air to fill up my tires after a run. I also don't like inconveniencing others by asking for their air/CO2. I don't like the small 12V compressors because they're noisy, don't have high CFM, don't have a great duty cycle, and the better ones are pretty expensive. And you have to store them someplace when you're not using them.
I don't like CO2 because you have to continually get the bottle filled (repeated expenditure of $$), it takes up a lot of space, and you could forget about topping it off before a trip and run out after filling only 1/2 of your tires. It's not an "endless" supply.
I don't like Yorks because the typical York mount makes you move the alternator down to where the smog pump bracket is. I don't like the idea that my alternator could be submerged in a water crossing while my air compressor, which is not a necessary accessory, is happily dry at the top of the engine bay. I also wanted to try something different that I had heard about from former TLCA President Red Fox (who is also a local club member of mine) as well as from a couple others.
Hence, the Sanden compressor. Found as an A/C compressor in some Fords, Volvos and possibly other vehicles, it has a slightly lower CFM as compared to Yorks, is tubular in shape which saves space, and the only "drawback" is that you have to add oil because it's designed to be lubricated by refrigerant like an Aisin compressor. But there's a port on the top that allows you to do that, so it just becomes part of pm.
The Sanden SD-510 is what I'm starting with, just because that happened to be what Neil Quigley gave me. The SD-508 I think is more commonly found in junkyards and is reputable for this service. The SD508 is a 5 piston compressor which can supposedly put out 9 cfm and 300 psi. I think the SD510 might do slightly more cfm. It's also a 5-piston compressor. The SD-508 has 8 cu. in. displacement, and the SD-510 has 10 cu. in. displacement. I did a quick calc and at 800 rpm the SD-510 should put out about 4.6 cfm with no backpressure. At 2000 rpm it should put out about 11.6 cfm with no backpressure.
Here are some links to websites that reference the Sanden compressor, one of which came from rusty_tlc on MUD:
Grungles Homepage
On-Board-Air Using a Sanden Compressor - Jeepaholics Anonymous
This is the mockup I did when I was in the middle of my power steering conversion. Since I am not running a smog pump, I used the smog pump bracket and tensioner as the foundation of my installation. The tensioner needs to be bent slightly to align with the mounting ears on the Sanden compressor, and the mounting bracket needs no modifications at all.
Now, the smog pump bracket is designed to fit 8mm bolts. The Sanden pump is designed to mount using 10mm bolts. So I went to McMaster-Carr and ordered a few sleeve bearings to make up the difference:
The mounting ears on the Sanden also don't exactly line up with the ears on the smog pump bracket, but a simple spacer from Ace Hardware (3/8" ID, 3/4" OD, 3/8" thick) will make up the difference:
Here's before/after shots of the sleeve bearings going into the mounting ears:
When the compressor is mounted, it's a little close to the stock exhaust manifold, but some heat shields should be able to fix that no problem.
This picture shows the wrap of the belt around the OBA compressor pulley. I have a JT Outfitters bracket holding my Saginaw power steering pump, and I'm using a pulley off of a Volvo 240, due to the wide belt it can accommodate like stock Toyota. This picture still has my old pulley with narrow belt shown.
This picture shows the front mounting bolt on the bottom. It's an M8x35 I believe, and it was just a hair too long so I added a second washer at the head end of the bolt to bring it back away from the pulley just a touch:
This picture shows the rear mounting bolt on the bottom. It's an M8x40 I believe, with the 3/8" long spacer to make up the distance between the ears on the compressor and the ears on the smog pump bracket:
A couple more views:
I'm using a Trollhole replica small courtesy light switch installed in the previously plugged hole in the dash to switch this thing on and off. By the way, in earlier FJ40s this little knob is installed on the right side of the pocket (glove box). My FJ40 has no holes in the dash to the right of the pocket, but I'm able to make use of other holes that are already existing.
The most difficult part about this installation, which also contributed a lot to the overall cost, was the unique connections on the Sanden compressors. The suction side is a 5/8" 45 degree SAE flare. The discharge is a 1/2" 45 degree SAE flare. As an aside, -AN flare fittings are 37 degrees and are not compatible with SAE flare. You can find fittings for SAE flare at your local Ace Hardware, but the only female fittings available are tube nuts. So I would have to get hard tube, flare the ends, and make some adapters if I want to go to any other type of fitting, like to barbs or NPT. Luckily I found some pre-fabbed swivels that helped me get to my NPT connections that I needed so I didn't have to fab up anything myself.
For the air connections, you can commonly find 3/8" and 1/4". I decided to go with ¼” because it seems to be more common. There are also different types of end connections, and I went with I/M as it’s supposedly the most common.
Parts from Ace:
Upper left: Quick-coupler: $4.99
Upper middle: Quick-coupler plug: $1.99
Upper right: Air chuck: $2.99 - Returned this to get one with a clip.
Middle left: 150 psi relief valve: $10.29
Middle: 5/8" SAE flare to 1/2" MNPT 90 degree elbow: $8.49 - for the suction side.
Middle right: 1/2" SAE flare swivel: $9.99 - basically two 1/2" flare nuts with a short piece of tube in the middle, pre-fabbed for the discharge side.
Bottom left: 5/8" SAE flare swivel: $9.99 - for the suction side.
Bottom middle: 1/2" SAE flare to 3/8" FNPT: $4.29 - I can get a Viair 3/8" hose and thread it right into this connection on the discharge side. - Returned this because I needed an elbow - not enough room.
Bottom right: 200 psi pressure gauge: $7.99
More Parts:
Air Hose (50 ft PVC) from Lowe's: $14.02
Manifold from Amazon: $24.02 after shipping
Filter/Coalescer from Amazon: $79.49 after shipping vs. $115 for the one on Kilby's site. This one is made by Interstate Pneumatics, has a metal bowl, and is rated to 300F.
Inlet Filter from Amazon: $30.15 after shipping vs. $28 for the one on Kilby's site. This is the same manufacturer (Solberg) as the one on Kilby's site and I'm assuming it's the same model. It has the same thread connection and is rated for 12 scfm. Heck, the one on Kilby's site may be the one rated to 10 scfm, so if that were to be the case this would be an upgrade. The next largest one is rated to 20 scfm and has a 3/4" NPT connection, which I didn't want. Hopefully this will work.
Air Chuck w/clip from Amazon: $10.37 after shipping
2 x 1/2" FNPT to 5/8" hose barb adapters from McMaster-Carr: $7.52 - this hose barb size is hard to find, but it's what I wanted because I don't want the hose to collapse. Maybe it will anyway and I'll have to redo the suction stuff.
3/8” Viair leader hose with integrated check valve (24” long) + 90-120 psi Viair sealed pressure switch from 4WheelParts: $50.61
30A relay and 2’ of 5/8” ID hose from O’Reilly: $8.08
From Ace:
1/2" flare to 3/8" MNPT 90 degree elbow: $4.49
3/8" coupling for above because they didn't have the above in FNPT: $4.29
Another quick coupler/plug set: $7.49
A couple hose clamps: $2.58
Some sheet metal for mounting the inlet filter: $6.29
3 x 1/4" NPT hex head plugs
3/8" x 1/4" reducing coupling
3/8" short nipple
2 x 3/8" 90 degree elbows
2 x 3/8" x 3" nipples
3/8" x 1 1/2" nipple
1/4" short nipple
1/4" x 1/8" reducing coupling
Total: $361.89, not including the compressor. So it’s pushing $400. Not really any way around it.
More expensive than a couple Viair 12V compressors, but I don’t want a Viair 12V compressor.
I'll need to find the receipt for the belt, sleeve bearings, compressor oil and teflon tape I had to buy, and the compressor was donated for the project but can be had anywhere from $30-$50 at a junkyard.
Here’s pictures of the assembly of the fittings on the compressor.
On the inlet, I have my 5/8" SAE-5/8" SAE swivel fitting, 5/8" SAE-1/2" MNPT 90 degree elbow, and 1/2" FNPT-5/8" barb all connected and ready to go.
On the outlet, I have my 1/2" SAE-1/2" SAE swivel fitting, 1/2" SAE-3/8" MNPT 90 degree elbow, 3/8"-3/8" coupling, and 3/8" Viair leader hose with integrated check valve all connected and ready to go (NOTE THAT THE CHECK VALVE IS BACKWARDS IN THIS PHOTO):
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