Yesterday while installing the AF1, I discovered what appears to be clean motor oil residue on the rear side of the wet tank and on the front of the differential. There are no drops on the pavement under the coach -- pavement is dry and clean. Almost as though there was a high pressure, very fine mist spray in that area of the coach. The cable / hose runway is directly above the area that's wet with oil.
About a month ago I had the differential serviced at Speedco. I'm wondering if I actually have a hydraulic oil hose failure or if the grease monkeys just did something stupid while they were changing the differential oil. I believe the oil residue is too light weight to be 80/90 weight. Looks and feels more like 30 weight.
Any ideas?
Mark,
Here are some random thoughts in no real order of importance. In that area there is limited place that the oil could come from. There is an area where the hoses are not covered in that same area where you could have a chaffed hose.
Have you been able to detect a loss of oil in the hyd. oil tank?
It could also be oil from the A/C hoses that run along the same chase. What little oil that is in the A/C system is thin but it would atomize through a chaffed spot and cover everything. If it was one of those hoses you would know pretty quick as your dash A/C would have quit.
Have you thought about a diesel fuel leak? It could be diesel from the return line.
It isn't likely to be the differential oil but... Did you have synthetic oil installed in the differential? If so it can seem pretty thin. Have you checked the differential to see if they overfilled it? The differential breather hose terminates in that same area on our coach so look for the end of it.
Pamela & Mike
Could be a chaffed hose. I need to look further. I was pretty focused on the AF1 install so I tabled this new development until I complete the AF1. I'll check the hydraulic tank today. I changed the hydraulic oil and filters also about 1 month ago so it should be full. Unfortunately the dash AC hasn't worked since I bought the coach. The differential oil is dino, not synthetic. The differential breather tube is something with which I'm not familiar. I'll look for that.
Diesel is a possibility I hadn't considered. The consistency of the fluid residue seems to be closer to diesel than to 80/90 weight. There was a drop of the mystery fluid on the bottom of the wet tank and also a drop of 80/90 on the bottom of the differential drain plug. I compared the two yesterday. The differential fluid was more viscous and darker. The mystery fluid was lighter in color and much less viscous. I'm recall thinking it had a greenish tint although I didn't think of diesel at the time. I didn't notice an obvious odor like that of diesel.
Thanks for the suggestions!
Smell it. Motor oil (hydraulic fluid), gear lube and diesel smell VERY different.
I did. It did not smell like gear lube.
Mark,
Probably a good idea to drop the tray and check hoses. Unusual for a leak there, as the tray does a pretty good job of protecting them, but guess it can happen.
"Greenish tint" might indicate AquaHot boiler fluid.?
If it were me I would probably just clean everything off, verify all fluid levels, take the coach for a drive and see what shows up. Hopefully it will become apparent where the fluid is coming from, or better yet, there won't be any leak.
Depending on build number, 2003 and newer (that was the changeover year, IIRC), the AquaHot should have pink/red GRAS boiler fluid in it, not the green that early 2003 and earlier coaches had. Has to do with the specific AquaHot design.
6106 was built with the newer AH design. I would expect Mark's 6199 would be, too. I'd be surprised if your 6160 wasn't as well (but run your AquaHot serial numbers past Rudy to be sure).
ETA - here is some info regarding the s/n of the AH and what fluid What Fluid Should Be Used In Aqua-Hot Coolant? (http://www.foreforums.com/index.php?topic=22749.msg174442#msg174442)
(and from what I've read, even though Century brand boiler fluid is GRAS and yellow/green, I would stay away from it)
The AquaHot unit in our coach was replaced by the PO a few years ago. It has the green Century heat transfer fluid in it.
I was not sure of what fluids were approved so I went to the AquaHot web site to find what they recommend. Seems that the pink Camco or the green Century fluids are OK with them. They just warn against using the green automotive antifreeze which is not GRAS. http://www.aquahot.com/FAQs.aspx#antifreezetypes
Technically, yes, but quite a few reports of the Century fluid sludging and turning brown on SOB forums. Keep an eye on it and don't mix fluids.
Update: got under the coach yesterday with some rags, degreaser and elbow grease. Cleaned the differential, wet tank and the "U" shaped galvanized cable tray. Ran the AH full blast in zone 3 (bedroom) for 2 hours. No leak. All dry. Today I plan to go for a drive and see how everything looks afterwards.
I use fluid dyes in some of the race cars. The Trans Am cars have coolers and tanks spread all around . A little dye helps to pinpoint the fluid source.
Drove the coach for about an hour today. Underneath everything is still dry and clean. I suppose I could call Speedco and ask if they pressure wash or steam clean before changing differential fluid. Seems unlikely.
Mike, I forgot to look to see where the differential breather tube terminates.