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Engine degreasing

Good morning forum: my silly question of the day. I have an annoying oil leak on my 8.3. It's coming from somewhere up top, towards the back of the engine. It has been here since I got it, and the coach marks it territory with a few drops everywhere. It not bad enough to put spots on the toad going down the road, but is making quite the mess in the engine bay. Impossible for me to tell exactly where without some degreasing I believe.

My questions are:  What do folks use to do this? How do you do this? And what to avoid doing while attempting to do this so I don't cause any more problems, electrical especially. I was thinking of using a three gallon yard type sprayer with degreaser, then some water to try and clean the areas so I can then diagnose where it's coming from and what I'm up against to stop it. I have power washers, but I'm sure I don't want to attack engine with these....
Keith and Dawn Hudson #18766
Current- 1999 U295 DFGE 40ft. - Build #5405
Coach Name: 4BUS4US
Previous- 2008 Nimbus CE338: 40th Anniversary Edition- Build #6486. 
Toad: 2021 Jeep Cherokee Trailhawk

 "I know something about a lot of things..a lot about something's..and everything about nothing "

Re: Engine degreasing

Reply #1
The best way to clean an engine without high pressure water, which like you mention can cause issues we don't need is to do as you mentioned and spray areas with a pump up sprayer with degreaser and then take a small brush and brush  heavy soiled areas and then rinse with a water hose.... Take care not to get any degreaser on the coach's paint.
Dub McBride 1996 270

Re: Engine degreasing

Reply #2
If you have a air compressor get a siphon gun and a gallon of mineral spirits,start at the top and work down,if you have baked on
heavey oily grease you can scrape or use oven cleaner,but do not leave on more then a couple of minutes,best if engine is hot when you clean,when done blow off with air,leaks on top could be where the breather hose comes out and or the valve cover,
keep us posted.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Engine degreasing

Reply #3
Thanks Dub and John....yes I believe that is the area, breather,valve cover...It's  not a bad leak
, just messy...I will need to use a sprayer to do the job, as I have an air compressor at my home, I would be doing this in a wash bay at my storage facility. I will probably take the coach out and run it for about 30 miles to get warmed prior.  It will be about a week or so until  I can actually do, just planning an attack...you say use mineral spirits instead of a degreaser? I may have to try that....thanks.
Keith and Dawn Hudson #18766
Current- 1999 U295 DFGE 40ft. - Build #5405
Coach Name: 4BUS4US
Previous- 2008 Nimbus CE338: 40th Anniversary Edition- Build #6486. 
Toad: 2021 Jeep Cherokee Trailhawk

 "I know something about a lot of things..a lot about something's..and everything about nothing "

Re: Engine degreasing

Reply #4
Safest on the electric and electronic components is:

Roll of paper towel and a can of WD40. Oh,and a pair of disposable gloves!
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Engine degreasing

Reply #5
If it's just oil and light grease the mineral spirits will melt it away fast,there is a smell to it,maybe use a mask.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Engine degreasing

Reply #6
When you say the back of the engine, do you mean towards the front of the coach, or the back of the coach?
Keith
2003 U320 38' #6197

Re: Engine degreasing

Reply #7
When I was at Cummins service they mentioned steam cleaning the engine to look for leaks but they did not elaborate on exactly what type of equipment they use.  I have looked hard to try to find a suitable steam cleaner and it seems that all I can find are flimsy little plastic ones for detailing cars and hot water/steam pressure washers which are overkill for the job.  Steam makes sense because it will effortlessly melt away grease and oil but it's mostly dry on the engine and electrical components.
George Mann
2002 U320 #5934
2017 Rubicon
2013 BMW GS
Waterford MI

Re: Engine degreasing

Reply #8
Keith, Top right side of engine, back of coach...as far as I can tell.
Keith and Dawn Hudson #18766
Current- 1999 U295 DFGE 40ft. - Build #5405
Coach Name: 4BUS4US
Previous- 2008 Nimbus CE338: 40th Anniversary Edition- Build #6486. 
Toad: 2021 Jeep Cherokee Trailhawk

 "I know something about a lot of things..a lot about something's..and everything about nothing "

Re: Engine degreasing

Reply #9
Try the easiest route first,the steam should be last resort,usually reserved for years of baked on grease and oil and dirt,it's a selling point for these shops,probably charge in the hundreds if not more.The steam will take alot of paint off for sure.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Engine degreasing

Reply #10
I degreased every ORED I sold with GUNK. Kerosene?  Oshkosh painted everything on the frame two coats of polyurethane shiny black.  Cat painted their 3208 shiny yellow. Every boy I showed under the bed too  called out "you got to see this"

Obviously politically incorrect, enviourmentally unfriendly. Local diesel dealer has a steam bay
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Engine degreasing

Reply #11

I use this for all my engines including the coach.

Simple Green - SMP13406 Extreme Aircraft and Precision Cleaner, 1 Gallon...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Engine degreasing

Reply #12
Thanks Chuck.... I'll pick up some of that and start there...
Keith and Dawn Hudson #18766
Current- 1999 U295 DFGE 40ft. - Build #5405
Coach Name: 4BUS4US
Previous- 2008 Nimbus CE338: 40th Anniversary Edition- Build #6486. 
Toad: 2021 Jeep Cherokee Trailhawk

 "I know something about a lot of things..a lot about something's..and everything about nothing "

Re: Engine degreasing

Reply #13
When my timing case ( not cover ) was the leak problem I wanted to clean it before taking it to Cummins Coberg Or.  what I used was certainly not the cheapest but I did not want water issues either.  So I bought a bundle of yellow towels from Costco and half dozen cans of brake clean.
  Started with a putty knife for the stuff that had been there for a while and a wire brush for the remaining stuff.  Wiping off as much as possible along the way. Lots of rags.  And then hit it with the brake cleaner which evaporates pretty quick and got it clean enough to see just where the leak was.
    Side bar, Of course Cummins wanted 5,000 + to fix so that didn't happen there.  I guess it quite the process to pull the cam and get that timing case off.    Ended up using permatex spray sealer, 4 or5 coats at Quartzsite.  So far so good. 🤞
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Engine degreasing

Reply #14
I also use what Craneman uses and a stiff bristle foxtail brush which helps to get into the hard to get to places.
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Engine degreasing

Reply #15
I spent a lot of time around the ISB engines back in the day.  Your ISC is very similar.  Look at this area of the front cover (circled).  If it's like the ISB's (I haven't personally confirmed), there is a rubber gasket behind it, and it just turns 90* and squishes the gasket to seal the front cover.  Oil is splashed up here by the geartrain and can leak around that rubber seal over time.  VERY easy to replace if it's the same.  Take a look.
Keith
2003 U320 38' #6197

Re: Engine degreasing

Reply #16
Simple Green - SMP13406 Extreme Aircraft and Precision Cleaner is highly recommended as safe, but is different than the regular NON-Aircraft Simple Green, which is not recommended.

Re: Engine degreasing

Reply #17
I spent a lot of time around the ISB engines back in the day.  Your ISC is very similar.  Look at this area of the front cover (circled).  If it's like the ISB's (I haven't personally confirmed), there is a rubber gasket behind it, and it just turns 90* and squishes the gasket to seal the front cover.  Oil is splashed up here by the geartrain and can leak around that rubber seal over time.  VERY easy to replace if it's the same.  Take a look.


That looks a lot like our 8.3 and the Cummins guy told me that originally they used a paper gasket. Not great.  He showed me the replacement one and it's a nice rubber impregnated metal that looks like it could totally do the job.
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Engine degreasing

Reply #18
When I was at Cummins service they mentioned steam cleaning the engine to look for leaks but they did not elaborate on exactly what type of equipment they use.  I have looked hard to try to find a suitable steam cleaner and it seems that all I can find are flimsy little plastic ones for detailing cars and hot water/steam pressure washers which are overkill for the job.  Steam makes sense because it will effortlessly melt away grease and oil but it's mostly dry on the engine and electrical components.

A lot of shops use a "HOTSY" pressure washer - I have one thats diesel fired - would NOT recommend it for our engine bays! As a note: they do an incredible job cleaning up grease!
2000 Foretravel GV320 4010 #5717
"SuperDutyFiver" on most other boards

*** East coast based - literally "all over the east coast!"