Broke down in Davenport - blown power steering line

chessie4905 · August 28, 2019, 12:34:05 PM

Did you ever notice if the pipe and wiring tunnel is covered above the hvac area like it is in the baggage compartments?

richard5933 · August 28, 2019, 01:15:55 PM

Quote from: chessie4905 on August 28, 2019, 12:34:05 PM
Did you ever notice if the pipe and wiring tunnel is covered above the hvac area like it is in the baggage compartments?

It's not, at least not in the way it is in the other bays.

Behind the air tank is a sloped sheet metal panel. Behind that panel is the upper section of the HVAC cabinet. This upper section is the return air chamber, collecting the return air from the cabin and directing it to the air filter down below.

The pipes and wiring go through this upper section of the HVAC cabinet, and this upper section serves as the 'tunnel' of sorts for the HVAC cabinet. The downside is that the pipes are at all isolated from the air flow or the coils.

chessie4905 · August 28, 2019, 02:08:11 PM

I'm talking about all the wiring and piping that comes from back and goes upfront. My hvac was removed and there is no enclosure over these items like the baggage bays. Can't tell if it was removed also, or never had the same enclosure.

richard5933 · August 28, 2019, 02:11:41 PM

Quote from: chessie4905 on August 28, 2019, 02:08:11 PM
I'm talking about all the wiring and piping that comes from back and goes upfront. My hvac was removed and there is no enclosure over these items like the baggage bays. Can't tell if it was removed also, or never had the same enclosure.

If your HVAC was removed, then likely there isn't going to be any type of covering. The upper section of the HVAC cabinet itself serves as the tunnel. Without the HVAC cabinet, there is nothing left to cover things up and they'd just be exposed in the upper section of the bay. Likely you'd have to build a tunnel to close them in.

The reason that the damaged copper line in my bus is so difficult to get to is my HVAC cabinet is still intact, and to open it up the air tank has to be removed first. At least on your bus these things are more accessible.

Next time I'm at the shop checking on progress I'll try and get a few pictures to show you what mine looks like. Hopefully they will still have things opened so you can see behind the air tank.

richard5933 · August 28, 2019, 02:27:50 PM

Here's a video I took by shoving my smartphone through the return air passage above the HVAC air filter opening. I wanted to get an idea of what was going on up there with the repair.

https://youtu.be/wmycgFTJ3r4

Not the best video, but it should give you an idea of what the upper section of my HVAC cabinet looks like (and of the not-so-great repair which is being redone.)

chessie4905 · August 28, 2019, 04:12:11 PM

Ok thanks. Mine is just like yours, no covering of the piping and wiring on the ceiling. I don't have a Dr. Pepper bottle though. Must have been optional equipment.👌

richard5933 · August 30, 2019, 10:06:49 AM

Couple of pics of the HVAC unit without the panels in place.

The cut copper pipe in the third photo is the one being repaired. The shop is waiting for the proper pipe to arrive, then they'll wrap things up. Both front flex lines are being changed out for safety since they are original, and the PS filter is being changed in case anything got inside the system during all this.

chessie4905 · August 30, 2019, 10:58:50 AM

Btw, the plywood panel on battery side with the hinged door is completely removeable. I see that as my compartment is completely gutted. In the process of installing a separate tank for the generator.

richard5933 · August 30, 2019, 11:05:28 AM

Quote from: chessie4905 on August 30, 2019, 10:58:50 AM
Btw, the plywood panel on battery side with the hinged door is completely removeable. I see that as my compartment is completely gutted. In the process of installing a separate tank for the generator.

Correct. Removing that plywood panel is how I've been gaining access to the lower section of the HVAC cabinet to clean what I can. The relays and controls inside the HVAC cabinet can also be access directly by removing the aluminum hatch on the forward wall of the next bay rearward.

For those looking but not sure what you're looking at, the yellowish things in the upper section are the air outlet ducts - they direct the flow from the fans in the HVAC cabinet to the ducts running along both sides of the bus. The entire upper chamber of the HVAC cabinet is the return air duct, pulling air from two outside vents and a few floor vents located towards the front of the bus.

richard5933 · September 04, 2019, 02:20:18 PM

Brief update on the repair progress with a few pictures. The first photo is the hole that was cut into the OEM copper when the battery cable insulation wore through. Nothing like a couple hundred amps arcing against a piece of copper carrying high-pressure oil to make a mess.

The second photo is the new repair, where the tech installed the correct gauge copper tubing.

Third photo is the repair that was done in Davenport. Quite obvious that the guy there didn't quite get the work done in a way I would consider professional - looks to me like he overheated the copper and generally made of mess of things, not to mention that he used a lighter gauge of copper than required.

All that's left is for them to double check for leaks, double check that the system is bled completely, and then road test. I'm planning to pick up the bus tomorrow.

Only concern right now is that the tech mentioned that he found some minor metal particles on the magnetic drain plug on the high-pressure line filter coming from the pump. There is a canister filter for oil going to the pump, so the metal particles likely came from the pump. I'd suspect this happened during the time the pump was run without oil when the line blew - probably about 20 minutes total including the time it took to get to the shop after the smoke cleared.

Pump still moves oil. Tech said that he can detect no unusual noise from the pump, and the steering appears to function properly. We had no steering problems on our recent trip to VA and back. While I hope that only minor damage was done, I've asked Luke to find me a replacement PS pump to carry onboard. Maybe I'm being a bit paranoid, but my hunch is that the pump will fail me at some point and probably sooner than otherwise would be the case. I'll feel better knowing that I've got a replacement onboard so the repair can be made when needed.

chessie4905 · September 04, 2019, 04:53:01 PM

You could take the pump apart and inspect it for damage. Nothing special about it.

richard5933 · September 04, 2019, 05:35:34 PM

Quote from: chessie4905 on September 04, 2019, 04:53:01 PM
You could take the pump apart and inspect it for damage. Nothing special about it.

I asked Luke about getting a rebuild kit, and he said that they only sell remanufactured pumps now, no kits. Not sure if there is a lot of advantage to opening the pump to examine right now - if I have a spare I can always change it should there be need. Otherwise, I'm opening the system and having to bleed out the air potentially an extra time.

My plan is to pull the magnetic drain plug after a few more trips to see if any additional metal particles are accumulating. It was cleaned yesterday, so that should tell me if any additional damage is being done. If there are more particles, I'll obviously change out the pump. If not, I'll keep driving along and keep the spare just in case.

richard5933 · September 05, 2019, 09:44:28 AM

Bus is home and parked in its spot. What a pleasure working with a shop with qualified techs that insist on doing things the right way.

No unusual noises, steering works as it should, and not a drop of oil out of place.

Done for now but will continue to monitor and get a spare pump to keep on the parts shelf.

Sebulba · September 05, 2019, 09:48:31 AM

If you get a spare pump, you will never need it. That's the way it always works for me. I would carry spare starters, alternators, brakes and other things. As long as I have spare everything is fine. If I forget to bring it on a trip, I will need it $:-\$

Just my experience.

Seb

Quote from: richard5933 on September 05, 2019, 09:44:28 AM
Bus is home and parked in its spot. What a pleasure working with a shop with qualified techs that insist on doing things the right way.

No unusual noises, steering works as it should, and not a drop of oil out of place.

Done for now but will continue to monitor and get a spare pump to keep on the parts shelf.

chessie4905 · September 05, 2019, 05:49:33 PM

When my nephew was dismantling a 1979 4905, he mentioned that if you bent the main
battery cable going through the wire chases, the insulation would crack, crumble, and fall off. Just a fyi. I'm going to check mine when I get the chance.