Broke down in Davenport - blown power steering line

richard5933 · July 26, 2019, 04:06:06 PM

Smelled a burning stench a few miles before exiting the freeway, which seemed to clear after a couple of minutes.

Exited and realized that I had no power steering. Pulled over. Engine bay is bone dry. Front axle area is bone dry.

Tried to refill the reservoir, then saw smoke billowing from the inside of the bus.

Shut down all electric and investigated. Saw oil mixed with the condensate dripping from the hvac compartment.

Looks like I blew a ps line over the hvac blowers. Dripping oil on hot motors makes a sooty stinky mess.

Strong armed to the Interstate Power Systems in Davenport. They're going to open the hvac panel and see what they can find.

Any thoughts on what might have blown in there?

Geoff · July 26, 2019, 04:50:47 PM

They are probably going to find a PS hose that rubbed through something sharp.

buswarrior · July 26, 2019, 05:36:09 PM

and are going to make you pay...

Are you going to sit there helpless until Monday?

find the rub through, cut it in half, jam a suitable sized pipe in the two ends, hose clamp, fill the steering, chase out the air and carry on?

is the power steering stock or a retrofit on that coach?

might be a metal line if stock... how are your brazing skills?

happy coaching!
buswarrior

chessie4905 · July 26, 2019, 05:53:08 PM

Should be braided or steel high pressure line. If it is not the return line, you aren't going to splice with a piece of pipe and clamps. Too much pressure.Something rubbed through line or layed against something sharp, like a screw or bolt. Probably from conversion work. I've had all my panels down and those lines are well protected and run through heavy gromnets at each bulkhead. For much lower cost till you get home, they can bypass blown line and run one in channels in floor under coach. That is where we ran ours in the 4104 when we added Shepperd power steering. Btw, we ran pipe from end to end and used a short length of high pressure hose to the ends to connect. 10 years+ and 150,000 miles, never a problem or leak. But repair it the way you and they feel best with. Good luck.

richard5933 · July 26, 2019, 06:20:43 PM

Looks like a metal line above the HVAC unit. Could be a braided line, but from the limited sight we have so far it looks to be metal.

Bus has OEM factory power steering.

Unfortunately, to open the access the air tank has to be dropped. They are working on that right now. Interstate runs a second shift.

Probably going to be Monday before it's fully repaired though. The 1st shift service manager happened to stop by and was thinking that they would need parts, and nothing is open here till Monday.

I'm still hoping they get the access opened up and find that it's just a fitting that came loose.

Oddly, my biggest concern isn't getting the leak fixed. Once they find it, I'm sure they will be able to repair it. My concern is that oil is everywhere in the HVAC unit. The whole interior reeks from oil right now. I asked them to do their best to clean up the oil, even if they have to use a few cases of electronics spray cleaner. Once they put the tank back in, I'm going to have a tough time getting things cleaned out.

I'll report back once I know more.

richard5933 · July 26, 2019, 08:19:55 PM

Ok guys... Didn't see this one coming.

The large red battery cable (2-0) that feeds the front of the bus crosses under the copper line for the power steering. The insulation had worn through, and when the conductor contacted the copper it made an arc welder. Instantly vaporized the oil in the lines and sooted up the air duct some. Oil sprayed everywhere.

The oil line has a half moon hole where the battery cable crossed it. Shouldn't be a problem sweating in a patch splice. Battery cable will have to be spliced from a couple of feet back of the damage uo to the junction block.

Damn lucky that the bus didn't go up on flames. My guess is that the first stench I smelled was the oil hitting the arc, and the smoke after we stopped was from the remnants dripping onto the melting cable.

Second time in Iowa. Second bus disaster. Last time in Iowa.

richard5933 · July 26, 2019, 08:28:55 PM

Question...

Did I damage my power steering pump when I drove it strong-arm the 10 miles to the shop? Not sure how long they last when they are run without fluid in the reservoir.

luvrbus · July 27, 2019, 02:53:24 AM

Quote from: richard5933 on July 26, 2019, 08:28:55 PM
Question...

Did I damage my power steering pump when I drove it strong-arm the 10 miles to the shop? Not sure how long they last when they are run without fluid in the reservoir.

{{

I doubt you did damage the way the Vickers vane type pump is design there is always a little fluid in the body unless you run it a long,long time

chessie4905 · July 27, 2019, 06:43:47 AM

That HVAC unit is designed to be removed as a module.

richard5933 · July 27, 2019, 07:44:05 AM

Quote from: chessie4905 on July 27, 2019, 06:43:47 AM
That HVAC unit is designed to be removed as a module.

Push come to shove, that's an option. But it's an option which would require evacuating the 25+ lbs of refrigerant and then recharging after. Since I don't have the equipment to do that, or to remove the HVAC unit itself in one piece, I'm going to hope I can get it cleaned in situ.

It doesn't look like it actually blew oil through the duct. What I think happened is that the vaporized oil and smoke rose up backwards through the intake, which should be much easier to deal with.

The relay board in the bay is accessible, and electronic cleaner should be able to take care of the that. I hope.

I will keep the a/c off for the drive home and won't run it until I can get in there myself to inspect and clean further.

Jim Blackwood · July 27, 2019, 08:45:44 AM

Copper tubing for a hydraulic line? Why would they do that?

Jim

chessie4905 · July 27, 2019, 09:07:19 AM

Copper plated steel? He may be seeing the copper from the melting of strands in the cable.

buswarrior · July 27, 2019, 09:12:35 AM

The bigger devil is wondering about the condition of the electric cabling...

The good bus refurbishers re-do all the heavy cables, right through to the battery box, starter, alternator, AC feeds.

And that's when the coach is only at its half life.

There's lots of us who want to think hard about a really close look at the big cables, for condition, and failed support, as the decades have shaken past.

happy coaching!
buswarrior

chessie4905 · July 27, 2019, 09:15:16 AM

Majority of larger outfits are setup to extract, recover and reinstall the removed refrigerant, if they have to remove the unit.

richard5933 · July 27, 2019, 10:42:00 AM

Generally speaking, the cable appears to be in good shape. It's got about 4" of damage to the insulation near the short, but after that it appears flexible and the jacket is still intact. Right now my objective is to get it home safely. The shop will remove the cable as far back as necessary, but they did open the tunnel in the next bay rearward and things look good there. I believe that they are going to do the splice in the next bay so I can get at it later on.

I consider this a manufacturing defect. That cable was not anchored properly and it was not shielded where it crossed the oil line.

If the HVAC unit has to be pulled the shop that did the compressor install can do it. Obviously that will also require draining the coolant as well, and will cost a few shekels. I'm going to get things gone and see where it stands then. Much rather have that all done back at home shop if it needs doing.

Is the line copper or steel? Don't know for sure, but it certainly looks like all the lines running through the tunnel are copper. Whatever it is, I am sure they will have a way to repair the leak. There are about half a dozen heavy truck shops on that intersection, so there must be a Parker Store (or equivalent) nearby.