So I separated the compressor as suggested and the air still went down as before. So leak is somewhere after the compressor and up to the tank. I guess I will have to get back up under and try to trace that blue plastic airline back to the wet tank.
1988 40 ft 8v92 newell
Coach name Big Blue
25 ft Haulmark car hauler with Andersen Anti sway
2012 Toyota FJ Cruiser.
What a day: I started out up front tracing the blue plastic air line coming from the 110 compressor. I got all the way back to the wet tank and I noticed the top of the wet tank had a check valve, Hmm so I stopped there and figured I would replace that as I did the 2 front tanks. Most was under the impression that there was no check valve on the wet tank I kinda thought why not, so it turns out there is. It is connected to a T with air lines on both ends. Well I put a wrench on that bugga and broke the T right off the tank. Oh s--t now what. Call someone? The coach is up but won't stay up gotta work fast so I fought to get the other lines off and drop the tank planning to go to town to get necessary check valve and fittings. Was able to remove th broken nipple from the tank. Well you know how it is when you go to Napa to get something for an emergency. We don't have one here but in Summerton there is one. Off to Summerton I go. Got back and the drivers side was all the way down while the passenger side was still up. Believe me when I say it was a very tight and trying time getting it all back in place. Starting at 8am and finishing around 3pm. So fired up the coach and raised it back up to get back under to check for leaks. all was ok. But that was not the source of my leak, Hmmmm. So continued to chase that blue line back to the engine compartment noticing that it elbows in to the main feed line from the compressor. But wait, is that another check valve? And is there a possible check valve in that elbow?
See Picture. So it seems that the 110 compressor runs direct to the inlet line at the dryer so it goes through the dryer before going out through the heavy black plastic line then into the wet tank. Will dig into that/those check valves in a few days, hoping that that is where I will find my leak!!!!
So does anyone think there is a check valve at the blue compressor line? Blow up the pic it looks like there might be and wouldn't that be necessary to stop any back pressure to the 110 compressor but there also is one at the compressor so maybe not. I will find out soon. Yea I know about putting blocks under the coach. Also had a full tank of air, oops. I knew it did not control the air bags.
1988 40 ft 8v92 newell
Coach name Big Blue
25 ft Haulmark car hauler with Andersen Anti sway
2012 Toyota FJ Cruiser.
On both coaches I've had the line from the engine compressor to the dryer was braided for cooling the air prior to entering the dryer. I see such a line in your picture. Since your dryer is different than mine I can't comment on all those check valves you found.
One thought that does occur to me would be to check for air flow out the dryer exhaust when using the electric compressor.
While waiting for the new check valve to arrive I disconnected the compressor line from the current check valve and ran the 110 compressor and sure enough air was passing out the check valve instead of going into the dryer. I removed the old check valve and pulled it apart and cleaned it and got it to work, reinstalled it and ran the main engine and got the tank up to pressure shut the engine off and the air pressure still dropped. There is no check valve where the 110 compressor line elbows into the dryer line but I did replace the check valve at the 110 compressor. Seems the only reason for a check valve between the compressor and the dryer is so the 110 compressor would not back feed to the main engine compressor but to go through the dryer. So the wet tank has a check valve on it and there is a check valve between the engine compressor and the dryer, even if there was no check valve between the engine and the dryer the new check valve at the wet tank should hold the air from back feeding so seems to me the leak is some where else.
On the wet tank there is a small 1/4 inch line on the end of the tank drivers side that goes up over the frame maybe to tag axle air bag? And there is another heavy line on top of the tank on the passenger side, not sure where it goes.
On the bottom of the wet tank is a Bendix D-2 automatic drain valve, I sprayed with bubble stuff and it seemed to be ok.
When the air pressure drops to where the 110 compressor comes on, the compressor will bring the pressure up in pretty good time so it seems to be working as should.
1988 40 ft 8v92 newell
Coach name Big Blue
25 ft Haulmark car hauler with Andersen Anti sway
2012 Toyota FJ Cruiser.
Update. Installed the new check valve at the air dryer and put a new pop off valve on the 110 volt compressor.
Ran the engine filled the air tanks shut off engine and still lost air according to the main air gage which is the wet tank.
1988 40 ft 8v92 newell
Coach name Big Blue
25 ft Haulmark car hauler with Andersen Anti sway
2012 Toyota FJ Cruiser.
Latest update, Took the coach in town to Bob's Diesel, he has a lift so he could lift the coach making it easier to work under the rig. I had an idea already where there was another leak by way of the inficon leak detector but could not verify with bubble stuff. The mechanic found it using simple green. It was a T connection with a nipple that was leaking quite a bit. It was loose to the point that he could push on it and make it worse. Probably been leaking for years. That fixed made a big difference but not 100% but I will live with it. It now takes all day and overnight to go to empty so if I was plugged into shore power I am sure the 110 volt compressor would keep the air up with no problem.
I am ready to put this air leak problem behind me now as we prepare to head back to Maine for our second summer.
1988 40 ft 8v92 newell
Coach name Big Blue
25 ft Haulmark car hauler with Andersen Anti sway
2012 Toyota FJ Cruiser.