Moving Air compressor intake out of intake manifold?

We did the test in our area, we had a rash of compressors failing, pumping oil threw them, the executive decision was to weld a fitting in the air intake and install a hose, that did not work and cost quite a bit. I installed a spacer plate and a $10.00 air intake from Bendix. Problem solved.
The boost loss on the air compressor is because a lot of people put in the wrong purge kit, and the boost flows directly threw the air compressor, and out the dryer exhaust.
I did not believe it would make a difference but the driver said it did.
There was no difference in compressor out put, the spec was 2 minutes from 50 to 90 it would do it in 70 seconds, at 1200 RPM same as when boosted.
The spec was change because Ford did not make it on their medium duty

 

cat sdp

have you thought about throwing the sdp compressor in the scrap metal pile and put a mxs / nxs bendix one in its place, something I've thought about but not followed up on to check parts interchangeability

Something to consider I guess

 

I found out today, that at idle, the compressor takes just as long to build air but with cooler air going in. Now I just need to figure out the best way to route it to my filter or gona look on bendix site for the filter to mount on side.

 

I ran a small(3"diax4"long) k&n type filter on mine for a month but found it got dirty too quickly in my application(I go into a lot of dusty scrap yards in the summer). I had it mounted about a 12' away from the compressor. I now run it into the elbow just before the air cleaner with a 1" id braided plastic hose. Seems to be holding up fine.BTW The bendix tech line really helpful when I called them.

 

On my ACERT I had problems with large fitting riping out of the compressor head and also there was a rash of unloader valves being coked up. After talking with Bendix I found out this is a common problem on ACERT motors due to CAT engineers not listening to Bendix engineers. The problem was fixed by plumbing the compressor intake into the crossover tube air tube coming out of the air cleaners. Been running this setup for 5 years with no issues and pressure build up is still within spec. Just make sure you run a hose that has enough strength not to collapse as the compressor kicks in...seen another it happen to another guy.

 

Thats good to know, I used to have to change my unloader valve once a year, then they came out with a newer more expensive one that has been better, but now that its a couple years old when its really hot outside it starts acting up.

 

just got my truck up and running, went and got the oversize air filter and reed valve for my 750 bendix. instead of pluming into the air in take. very simple to do. bendix claims it last 25000 miles before you have to replace it. only cost $4 for the filter at car quest.

 

As others have since confirmed this is a real thing. If I have my foot in it I can tell with my ear ( and confirm with my boost gauge )when my air gets down to 100 psi and the compressor starts to work. It'll swallow up the extra air for the few seconds it needs it and then my manifold pressure will bounce back up once my air is all topped up. This phenomenon will not affect anything at idle, or high idle.

The only debate is whether it's worth doing something about or not.

 

The additional parasitic load on the motor would not cause boost pressure to drop, just the opposite, if that's your question . RPM has no real influence also, as long as I'm at WOT and spooling all I can the fluctuation in boost pressure will directly correlate with the compressor engagement only.

 

correct but for the $37 cost for the reed valve and air filter. just one less place for a boost leak to start. and for the $4 filter even if i have to change it every oil change it is worth it.