New Alpine owner brake flush question

[SDAlpine]

Hello, I recently bought an 01 34 FDDS from the original owners and I am in process of getting some of the maintenance up to date. I’ve read a lot about flushing the brakes on here and there seems to be a wealth of knowledge on these Alpines on this forum. I have attempted to do a flush with a power bleeder also tried to manually bleed the brakes. I have read some say that you have to have some Cummins software to open up the ABS pump to be able to flush through it. I spoke to a Cummins service advisor in El Cajon and he is telling me that can’t be done through their diagnostic port. Does anyone know what computer diagnostic tool is used to accomplish this brake flush? I really want to get it done ASAP and it doesn’t seem like to many shops are interested in doing it. Below are a few pictures of the new to me coach. First diesel pusher and I am excited to start taking my family out camping in it.

[Alpine36]

Congratulations on your new purchase, that's a fine looking coach!
I know you won't want to hear this, but on your 01 you should probably pull the wheels and remove the calipers to lubricate the caliper slides, as I believe the 01's had the two piston floating calipers like our 2000. I could be wrong, but sometime in 01 they switched to 4 piston fixed calipers, but hey, a complete brake inspection never hurts.
Besides, you need to pull the rear wheels anyhow to access the bleeder ports, especially on the the 4 piston calipers. You shouldn't need to tap the abs computer to bleed the brakes.
Simply have a friend work the brake pedal with the key off and bleed them just like any conventional hydraulic brake system utilizing the 12v booster back up pump. Helpful hint, remove the two bolts holding the brake fluid reservoir to the firewall first, dump out the old fluid and leave the reservoir loose for filling. Note, all 4 calipers and rotors are the same front and rear. The original two piston calipers should be cast with part number 4153222 on the backside. Hope this helps, and good luck.

[Mjw2347]

One idea for service — Check with Oceanside Truck and RV Repair (Mike) to see if they can help… If so, make sure you share the Forum findings with him. Mike is knowledgeable but in past he has appreciated Alpine related info I’ve shared with him… Phone # (760) 722-2345. Good Luck!

[GeneCanfield]

I have a 2009 with the 4 piston calipers but I went through the procedure when I purchased mine. The hardest part was taking the wheels off. I had to buy a torque multiplier to get the lug nuts off and wrestling with the tires is a chore so bring some help. Other than that it was the same as bleeding any auto brake system. I bought a small pump with a hose on it to pump clean fluid up into the master cylinder to keep it full and simply kept pumping clean fluid through until it ran clear at each wheel. Good time to check all of the pads and calipers. Just like your car only bigger.

[wolfe10]

In bleeding the brakes, start by siphoning out/pumping out the master cylinder.


Fill, "stir it up" with a small clean screwdriver, etc. Drain it again. Repeat until you are starting with totally clear, clean brake fluid.


I would never start by running old, hydrated brake fluid through the system.


And, rather than pumping the brakes (brake pedal) which can be hard on the master cylinder (running the seals over areas that are new and may have rough spots) I suck fluid from each bleed screw. Ya, you could use a more expensive pump, but I use a 30 year old transmission hand operated suction pump to pull fluid through the system.

[andy29847]

My 2001 38" FDDS has 2 piston calipers. I do not have to pull the wheels to bleed the brakes. I use a power bleeder that looks like this:



The fluid comes out of each bleeder, but not very fast. I do not have to connect with a computer to bleed the brakes.

My coach was very low miles when I bought it 4 years ago. I learned about the brake system the hard way. Coming home from my first trip, I felt the peddle get mushy. My brakes did not go away, but I knew I needed something. When I tried to bleed the brakes at home, the driver's rear would not bleed. I was using the old fashioned method, pressure on the peddle, open the bleeder, fluid comes out, close the bleeder, release the peddle. I took the coach to a local shop for help. My mechanic had a computer with a Cummins program that included a module for the brakes. He was able to see the ABS modulater through the computer and mannually open it. That solved the fluid problem, but while I was there, we pulled off the wheels for inspection and found other problems. A couple of the brake disc were cracked. A couple of the ABS sensors showed signs of heat. I went to the local NAPA store and bought new brake disc, calipers, brake pads, and ABS sensores and replaced all of the old parts. FWIW, I bought calipers that have all metal pistons as opposed to the stock calipers which have brake pistons with a coating (that swells and causes sticking which causes heat which causes the brake problems I was seeing). After the parts were replaced, my brakes worked great. A year later, I decided to try and replace the brake fluid again. The driver's rear still would not bleed by normal methods. I noticed when I was under the coach that the brake on the driver's rear wheel was not working. I went back to the repair shop. My guy diagnosed that ABS Modulater as bad (internal soleniod not working). It took a couple of weeks to get a replacement - it had to be made after we ordered it. Since the modulater was replaced, my brakes have been trouble free.

The brake system found on motorhomes like mine is the same as what is used on many school busses and medium duty trucks. I works great as long as the vehicle is used on a regular basis. The problems come if the vehicle sits up for long periods of time (like most motorhomes). The brake fluid asorbs water, and the water corrodes internal parts. In addition to the corrosion, the water makes the coating on the brake pistons swell, which causes the brakes to stick. Most of the gurus around here replace the brake fluid in their motorhomes every 2 years.

Here are a couple of links from past brake discussions:

https://www.irv2.com/forums/f104/ble...on-484857.html

https://www.irv2.com/forums/f104/bra...ch-395383.html

good luck!

[andy29847]

One more thing...there are 2 connectors for diagnostics under my dash. One is for the engine, one is for the ABS system. You have to use the ABS plug to read the modulater.

Also, I found that my ABS diagnostic plug was wired wrong from the factory. I haven't read of any others that were wired incorrectly, so mine may have been a Monday morning job. If I remember correctly, one of the port power leads was transposed with one fo the data leads.

[SDAlpine]

Thanks for all the info. I am waiting on 2 more Toyo M177 tires and then I’ll be installing them and seeing if we missed a bleeder valve. I looked under my dash under both sides of the wheel and couldn’t find any diagnostic plugs. I will look more thoroughly tomorrow. I did see a diagnostic port in the back service bay by the fuel filter but nothing under the dash.

[andy29847]

It's on the passenger side on my coach. Here is a photo of the gear behing the trim panel. I took my engine diagnostic port out of the bracket to hook it to a Scan Gauge D. The ABS port is the one rermaining (with a cover on it).

[SDAlpine]

Thanks to you guys I did some poking around and found this above the entrance steps. Does anyone know what type of scanner / diagnostic tool would plug into this ABS port?

[andy29847]

The connector is a 6 pin Deutsch connector. This was industry standard on trucks 20 years ago. Newer trucks mostly have a 9 pin Deutsch plugs. There are some other variations, but most scanners come with 3 or 4 plugs including the 6 pin one.

The real question is which scanner. I don't have an answer for that. My concern would be that a cheaper scanner might only be capable of reading trouble codes and not have any other capabilties. The guy that worked on my camper used a loptop loaded with a program for scan work. He had a pouch of adapters and cords to connect to the trucks.

[Mitimet]

I decided this is a good post subject to add my tool experience to. Newbie at this too but have good+ mechanical experience. First I have never had good luck bleeding brakes on any vehicle except for this time with this tool!! This was a Fantastic successful experience, even on this big beast. This bottle that holds the new brake fluid has a check valve that keeps the master cylinder from going dry. It has a little metal clamp to help keep in the master cylinder. I took advice from another post and unbolted the master cylinder to make this much easier. Very hard to fill master cylinder otherwise. The bleeder bottle hangs conveniently where ever you want. Hook up your garage air compressor hose to the bleeder bottle, press the black hose bleeder fitting to your rv brake bleeder and squeeze the bottle trigger. When ready open your rv brake bleeder and the suction starts pulling fluid from the bleeder into the reservoir. I did this after replacing my rear calipers. Bought this from Amazon, was from Firstinfo tools some time ago. Many different companies carrying basically the same product now. Prices about $30 to $90 depending on which you buy. No longer afraid to bleed brakes.
Mark

[Mitimet]

Mine is a 2000 36FDS and I had no issues with ABS system. Mark

[wolfe10]

And, after "vacuuming out" the master cylinder to insure that I would not be pulling hydrated/contaminated brake fluid through the system (equipment below) I used this pump to suck a vacuum and pull fresh fluid to each brake bleed valve. Use a few inches of cheap clear PVC to down size to brake bleeder tight fit.



https://www.autozone.com/test-scan-a...gun/142102_0_0


Actually, the one I use is many decades older, but same concept.