Air compressor issue. Up and running now...

John316 · September 27, 2013, 11:06:21 AM

Last night when we pulled out of our campsite to dump, the bus aired up really slowly. Didn't think too much of it.

This morning pulled out to leave, and low air buzzer came on (after we had totally aired up). Basically our air compressor was not running. I replaced the governor, just in case that was it. Still no joy. I finally decided it must be the unloader. That was a pita to take that cover off. I couldn't even get one of the bolts all the way out, because I didn't have enough clearance. I sprayed a bunch of PB blaster in there to hopefully free the unloader, and put it all back together.

I aired up, and has been doing fine. Only problem is the compressor doesn't seem to ever unload. It seriously purges every minute or less. My buddy at MCI thought it was a check valve up front, that I am going to replace. I really hope that is it. I don't hear a lot of air leaking with the bus on or off.

Any other ideas that you want to throw my way? I will be dropping by the MCI warehouse in Louisville this afternoon to pick up the check valve. Anything else I need?

Thanks,

John

Len Silva · September 27, 2013, 11:50:23 AM

I think it almost has to be the unloader. Maybe you loosened up some trash that has it stuck.

Dave5Cs · September 27, 2013, 05:03:25 PM

John if you have an air dryer it maybe stuck open(purge and or check valve at top inside and can be serviced easily depending where your is.

Dave5cs

luvrbus · September 28, 2013, 09:28:15 AM

Check the easy stuff first like for kinks or restrictions in the governor lines worn pistons in the unloader will cause that also

good luck

John316 · September 28, 2013, 06:00:13 PM

Thanks for the thoughts.

We went ahead and got a rebuilt compressor. We have started to pass this green/grey oily goo, so probably time for a new compressor anyways. Clark Power in Georgetown think they can work us in on Monday. On the road, I don't have the tools to change it out myself. Not to mention, that is right on our way, so shouldn't be a big deal.

Anything I should worry/watch out for with the Clark boys?

I will replace the check valve Monday, check for kinks, etc.

Thanks,

John

luvrbus · September 28, 2013, 08:44:39 PM

Wise choice John that is what I do seems like when a compressor has problems it never stops till it is changed

John316 · September 28, 2013, 08:47:17 PM

Clifford,

They are saying that they think it will take about 8 hours. To me that sounded about right. What do you think?

Thanks,

John

Seangie · September 30, 2013, 07:31:14 PM

John - not sure about an MCI but it took me about 4 hours to change mine on the eagle and that's someone who had no idea what they were doing.

I'm not sure how hard the compressor is to get to on the MCI but on the eagle it was right under the bed on the back side of the engine. All it took was unhooking lines, 4 bolts and pull the old one. Swap the gear and 4 bolts back on to put the new one on. A good mechanic shouldn't take all day to swap out unless there are other issues or its difficult to reach. Cliff should know spot on how long it takes on an MCI.

-Sean

www.herdofturtles.org
1984 Eagle Model 10S

niles500 · September 30, 2013, 08:27:25 PM

YUP 8 HOURS would be a lot for r/r including a rebuild

Dave5Cs · September 30, 2013, 10:04:50 PM

Talked to Luke today and he was saying as he remembered they used to either pull the motor or pull it forward about a foot to make it easier to get out on the 5's don't know about the others.

Dave5Cs

luvrbus · October 01, 2013, 06:30:21 AM

8 hrs is a little high but that compressor is not a easy task,the fuel pump drives off it then most places when they get the compressor off remove the drive to check for wear and replace the bearings he has a 60 series engine fwiw

John316 · October 01, 2013, 06:50:52 AM

Thanks for the info and thoughts.

So here is what happened. We went to Clark Power Services in Georgetown on Monday. I called them Saturday, and they said they would for sure get us in Monday. I showed up there, and what do you know, they said they MIGHT be able to LOOK at it when I brought it in. Personally, I really didn't care for their shop and guys there.

I started calling around, and Bluegrass International was right down the road, and had room for us. Great shop, great folks, and great mechanic. They had it replaced in 5 hours, which is honestly what it should have been.

They also found our intake manifold was starting to rot through. Sam Caylor overnighted us another one out yesterday, and they are putting that on this morning.

Bottom line? Avoid Clark Power Services in Georgetown, if you can. International, just down the road, is a great shop (from our experience).

Cheers,

John

luvrbus · October 01, 2013, 07:28:19 AM

Here WW Williams has a backlog of over 2 weeks they are running 2 shifts with 80 mechanics and cannot keep up with the million mile engines Cummins and Volvo are the same way in Phoenix

Cummins told me it will be the end of OCT before they can do some warranty work on a generator they did for me it sucks

Jon · October 01, 2013, 08:09:12 AM

I second the comments about Clark, this time the folks in Knoxville.

I bought my coach without any historical information on service. I reached a point where I wanted to do a coolant change. There are some critical issues relating to coolant. The original Detroit spec is Power Cool (2 year coolant) and it requires periodic SCAs via a filter / conditioner. Mine had a Detroit part number item where the coolant conditioner was and I needed to know if it was one that added SCAs or if it was a blank used for the 6 year coolant which is a completely different chemistry. The 2 and 6 year coolants are not compatible and use of conventional coolant in a system that has 6 year causes the 6 year to revert to a 2 year.

I asked the parts guy if he could tell me what the part number was for, a blank or a conditioning filter and I got a smart @$# answer he just gives out parts. The Service Manager was equally obtuse telling me to just buy Power Cool and that they don't have the filter, but the local Freightliner shop does. I didn't want to buy power cool if my system had the 6 year coolant, but after the BS I just got new 2 year coolant and did not bother to flush the system assuming I would be OK.

I just took my business to Truck Pro. Clark must have more business than they can handle.

luvrbus · October 01, 2013, 08:22:02 AM

Some dealers just do not want to work or have anything to do with buses they don't seem to mind doing the engine manufactures responsibility but when it gets to the OEM responsibility they seem to draw a line in the sand

That sometimes can be nightmare after all their mechanics are trained on the engine and transmissions only I am not defending their actions but it is a 2 way street with the crap the manufactures add on and the way they do it

They are clueless when it comes to buses I saw this first handed at a Volvo dealer in Phoenix trying to replace a D13 engine in a H-45 for Arrow that failed in less than 50,000 miles those guy's had no idea where to begin or end I saw the same in Vegas at Freightliner working on a MCI with a 60 series it was circus act