Hydraulic System for Cooling Fan

[djpauls]

Just had the radiator rebuilt and the R&R resulted in loss of fluid from the Hydraulic system that powers the cooling fans and power steering. After reassembly the tech topped off the reservoir with 1 1/2 gallons of AW 47 hydraulic oil. I checked the owner's manual and confirmed with Monaco service that the fluid should be Dexron 3 and does not mix with AW 47. The engine has not been started. I am thinking that I should remove lines from the lowest point of the Nelson Hydraulic Filter Reservoir, drain completely, replace filters and then refill with Dexron 3. Any other thoughts?

[wolfe10]

Absolutely drain and fill at a very minimum. Assume it was run after replacing the fluid (at least to move it out of the shop). So, wouldn't hurt to drain, fill, take off the return line and run at idle (adding fluid as fluid comes out the return line) until clean ATF comes out.

Were it mine, I would do that and then do it again after 100 miles or so. Fluid and filters are cheap. As you have probably found out, hydraulic components are NOT.

BTW, there is no standard here. Some hydraulic systems run on hydraulic fluid, some on ATF and some on motor oil. Ours happens to run on Delo 400 15-40 motor oil.

As long as you use the fluid that the whole system was designed to run on AND DON'T MIX OTHER FLUIDS WITH IT you are good to go.

Brett

[djpauls]

Hi Brett,

I know for a fact that the engine was not started because it was done in my building and I have the keys. Any additional comments are appreciated.

[wolfe10]

Then, drain, filter change and new fluid should do you just fine.

Brett

[dickandlois]

Brett, is right on top of the issue and you also. Mixing of the fluids is just not good in itself. Many of the seals used in hydraulic systems do not like some of fluids used.The fact that you followed up after finding what took place will save you in many ways down the road.

Safe and happy trails. R.M.

[Butch39]

With our 2007 Monaco Diplomat, I was totally confused as to what fluid was used within the system. The owners manual was not clear when you service the hydraulic system. As per the manual, it spoke of using 15w40 motor oil then two paragraphs later speaks of using dexron 3 only. I then e-mail Monaco and rec'd a reply which stated,"if the oil is red it's dexron, if yellow(amber) its motor oil, if it's clear it is AW 46 hydraulic oil", but have to know what was in it before your change. My manual does not mention using AW 46. Mine was filled with 15w40 motor oil.

NOTE: As we purchased this rig as pre-owned, last July 2011, we are in the dark as to what maintenences have been done and when. Contacted dealer where purchased, and was very vague as to what was done and when. So when the rig comes out of winter storage this spring a complete total service will be done on the motor home and the generator. This will give us a starting point for services in the future.

[wolfe10]

Butch,

That is always the safest approach.

I am surprised, however that a dealer was vague on what was done (unless you spoke with a salesman). Did you contact the service manager? I PROMISE YOU that they did not do work or install parts for which there was no ticket! The ticket could be in the previous owner's name, new or used vehicle department (as an internal ticket) or in your name depending on when the work was done.

Worth another call.

Brett

[hermanmullins]

Butch, give a call to Monaco. Have your coach number when you call. At this time you can register your coach with Monaco and they can help you on what fluids were used. You should have a Cummins 350 or 400 ISL. You can go to a Cummins dealer and get the maintenance schedule and possibly a engine manual.

Good Luck.

[djpauls]

After reading Butch39's response I decided to do some more research. The tech who changed the radiator assured me that the fluid was not Dexron 3 even though the owner's manual and Monaco tech service claimed it was. I checked the build date of the chassis 2/23/2000 (12 years ago tomorrow). Apparently Monaco changed to Dexron 3 sometime after my coach was built. New filters ordered and will top off with AW 46 hydraulic fluid before my next trip. Thanks to all for your help!

[Butch39]

Butch,

That is always the safest approach.

I am surprised, however that a dealer was vague on what was done (unless you spoke with a salesman). Did you contact the service manager? I PROMISE YOU that they did not do work or install parts for which there was no ticket! The ticket could be in the previous owner's name, new or used vehicle department (as an internal ticket) or in your name depending on when the work was done.

Worth another call.

Brett

Brett,

I had all info necessary to obtain the service records but I think that some services could have been done elsewhere. The dealership removes all references to the previous owner before sale. But we knew who the PO was as we had found some past insurance papers. The service person was not to helpful and was not willing to give any info another than what was directly asked for. Something about company policy; to protect the private matters of the PO.

So again, I believe that a complete service is the only answer......that at least we will know what and when the services were performed. Gives us a starting point for any future services. Brett, the service mgr and I do not see eye to eye. He is less than honorable, and I told him and the General Mgr. in a face to face conversation. I'm a retired auto/truck/bus mechanic and finished working as a parts mgr within the Ford dealership system. Know all to well about the "no ticky, no laundry(parts)"....must be charged somewhere, to someone. At my age, it's not my first rodeo.....was born at night...but not last night. Hope you get my drift.....

[Butch39]

Butch, give a call to Monaco. Have your coach number when you call. At this time you can register your coach with Monaco and they can help you on what fluids were used. You should have a Cummins 350 or 400 ISL. You can go to a Cummins dealer and get the maintenance schedule and possibly a engine manual.

Good Luck.

Have registered the motor home with Monaco under our name, have contacted Monaco as to inquiries about a few concerns and was promptly given requested info. We have all the owners manuals, have read all, and in fact, have purchased and read fully a new owners manual more than once. Have rec'd all required schedules as to motor home, generator, engine, and trans(Allison) from related websites....have a large three ringed binder with over fifty pages of schedules, and "know how to do" info. I think we have covered almost all the bases.......... We are not new to motorhoming, but we are new to the "DP concept".

Thanks for your response, all info is appreciated.