Jet Air Ride suspension system

Hobbes · May 31, 2016, 10:30 PM

Hi All. I've searched these forums and don't see a post that answers my questions, so I'm hoping someone has dealt with this in the past. I have a 1989 Itasca Sunflyer with the Jet air ride suspension system with Park and Level. We bought the coach 9 days ago, and the system worked well. Last weekend, we took our first trip, and for most of it, the Jet system worked great. It worked on the way to the campground, and it worked great to level the RV when parked. The next day, I drove over to the dump station (who knew a wife and two kids could use so much water in one day?!), and the system worked perfectly on the drive over and back, and again leveling the RV when parking. The next day we packed up to leave. When I started the engine, the compressor light didn't come on like usual, which immediately caused concern, as it always came on right away when turning on the key. Flipping the switch between manual and automatic had no effect. Basically, between one day and the next, the compressor ceased to function. Fortunately, there was enough residual air in the system that I was able to leave it on manual for the 60 mile ride home and we made it. I even stopped at a gas station on the way and manually aired up the bags as much as I could with the weak gas station pump.

The control box has power, and when flipping the Up/Down switches in Manual mode I can hear the air solenoids working.

Searching the web revealed that there are three likely causes for the sudden loss of the compressor: a bad ground at the compressor, a bad solenoid at the compressor, or a blown inline fuse to the compressor. I downloaded the Jet manual, and it says the inline fuse is "located close to auxiliary battery". Well maybe on some RVs, but not on mine. It's not in the under-hood fuse panel either.

All this brings me to my initial questions for the group:
1) Does anyone with a similar Sunflyer or Chieftain know where the dang fuse is?
2) Does anyone have a cross reference for the solenoid? Wondering if it's a NAPA/AutoZone/Etc. item or if I need to order it from Jet. (If I need to I'll pull the old one out and take it to NAPA, but I'd prefer to have a new one first so I only have to crawl under there once to swap it out and test it.)

Thanks in advance for any help!
Dan

Rickf1985 · June 01, 2016, 10:51 AM

Hi Dan, I have the same system in an 89 Chieftain. Most of the parts are available over the counter. I was just discussing this on another forum with someone and he bought the solenoid aftermarket. I will get the info for you. The ground on these is a big issue since it is grounded to the compressor mount which in turn is mounted to the frame rails but not bolted to them, just clamped. At least in mine. I ran a new ground wire directly to the frame. But at the same time I also put in a new Viaire compressor and new hot wire from the main panel. I have a 40 amp inline fuse up front and a 30 amp in the back before the compressor but I cannot for the life of me remember where the original fuse was. You will probably have to start at the compressor and follow the main feed wire back to the source. If the switches are getting power then the main fuse is good, all power comes from that wire. I am thinking either the compressor quit or the solenoid died, most likely the solenoid.
Here is the solenoid he got.
https://www.amazon.com/CONTINUOUS-SOLENOID-RELAY-CARTS-1114208/dp/B00BGTL9GI?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o05_s00

On his he found a blown Accessory fuse which was for the controller so check all of your fuses and circuit breakers.

Hobbes · June 01, 2016, 09:39 PM

Thank you Rick, that's extremely helpful.

Tonight after work I used my garage air compressor to fill the airbags all the way so I could really crawl around under there and get a good look at everything. I traced the wire from the compressor all the way up to the cab and I could not find a fuse holder. There were several places where the wires were hidden, so I suppose it's possible the fuse is hidden up there somewhere. I need to dig out my voltage meter so I can just check to see if I have voltage back at the solenoid. At least that would point me in the right direction. If I have no power, I'll follow your advice and just run a new, fused wire all the way back. At least then I'll know where the fuse is in the future! I'll also run a new ground wire direct to the frame.

Some more bad news tonight...the onboard air tank has a pinhole leak in it, so now I also need to replace the air tank. I'm starting to think about just chucking all the old pieces and installing a new Viair system like you did. Did you use something like this: https://www.amazon.com/VIAIR-Heavy-Duty-Onboard-System/dp/B000X9O79I/ref=pd_sbs_263_3?ie=UTF8&dpID=41FfUtYcIaL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=D0X9WKRRKJS7W12XD4JJ

Again, many thanks for your help!
Dan

Rickf1985 · June 02, 2016, 11:48 AM

Dan, You do not want that system only because of the duty cycle of the compressor, 33%. You want a compressor that can run for long periods if need be. I forget which compressor I used (all I replaced was the compressor and the solenoid with a relay) but it had a 75 or 80% duty cycle. They also have 100% duty cycle compressors. On the compressor the one thing to watch for is CFM rating ,more is better. Pressure is secondary, you will never need more than 150 lbs. of pressure but CFM is what gets the job done faster.

I want to point out a safety thing here, VERY IMPORTANT! Put heavy duty jackstands under the frame when you are under there!! If any part of that air system breaks or blows out while you are under there you could be squashed! Mine will put the rear bumper and side cabinets within 4-6 inches of the ground at full deflation! I know for a fact that I am fatter than that even in my best days. I also know I can't hold up 10,000 lbs. for very long. Be safe.

Rickf1985 · June 02, 2016, 11:59 AM

From the Viair site this is the system you would want if you want to buy a complete system. I don't think the tank is as big as yours though and you do need a decent amount of reserve air for the suspension. I would just buy a compressor, tank and solenoid or relay.But go for the 100% duty cycle compressor to be on the safe side. I have two compressors and although I do not have it all hooked up yet I am eventually going to set up the second compressor so that it will come on at 85 lbs. pressure and shut off at 100 lbs. That way if the first compressor starts falling behind or there is a large demand for air both compressors will run until caught up and then one will drop out. under normal circumstances only one will come on. If for any reason that one fails the other will kick in but just at a lower pressure and shut off a little lower. Sounds complicated but not really in practice. I want to get my air horns working and run them off of this system instead of the dinky compressor they were on that failed.

http://www.viaircorp.com/oba-constant.html

Hobbes · June 02, 2016, 09:18 PM

Good advice on the compressor duty cycle, I hadn't even noticed that last night.

Today I went out and yanked out the tank and pulled down the compressor platform (with a couple of 6 ton jackstands supporting the coach). I hooked the battery out of my four wheeler directly to the compressor and voila...the compressor works. Before this issue the compressor worked very well, quickly raising the air bags when needed, so I decided that for now I'm going to keep it in the system. So I came back in the house and ordered a new solenoid and a new 4 gallon aluminum air tank, along with enough extra fittings and air hose to mount the new air tank in a nearby side cabinet, rather than under the coach. the new tank location will make it easy to also attach a nice long air hose for airing up the tires, blowing up swim toys for the kids, etc.

This weekend I'll make a new support bracket for the compressor and solenoid, clean all of the electrical contacts, and run a heavy ground wire to the frame. The new solenoid and air tank should be here on Monday, so once I get it in and working I'll follow up again to let others know what I found out along the way and what the final problem turns out to be (could still be that mysterious inline fuse...still haven't located that or run a new wire).

Rickf1985 · June 03, 2016, 09:28 AM

Hobbes · June 07, 2016, 05:56 PM

So I finally found the mystery inline fuse:

Hobbes · June 07, 2016, 05:59 PM

It was hidden behind the drop-down panel of the under-hood fuse/circuit panel. The fuse in there was a 15 amp, where Jet specs a 30 amp. I'm hoping that's why it blew so dramatically. I replaced it with a new heavy duty inline holder and a 30 amp fuse, and the compressor works just like it's supposed to. I also got some spares in case it ever happens again while we're out on the road.

M & J · June 07, 2016, 06:00 PM

Hobbes · June 07, 2016, 06:10 PM

Here are pictures of the shiny new 4-gallon air tank and the old, rusted out 2-gallon tank, and the compressor mounting bracket I made from the old tank. For those that haven't seen this system, the old air tank was bolted to the compressor, and then both were clamped across the frame rails. The new air tank is mounted in a side storage bin for easy access, with the addition of an air hose for miscellaneous inflation jobs.