Hydraulic fan finally fixed, unbelievable solution!!!!

[Frank McElroy]

Keep in mind that Monaco had a recommendation to change out AW-46 to ATF fluid in cold climate applications - we're talking temps below 32 DF.  This is because the high viscosity AW-46 was blowing out the oil cooler especially when temps got into single digits.

Also, look at the hydraulic system layout.  On my 2008 Dynasty, the single internal tank filter filters all oil going to the hydraulic pump that feeds both the steering gear box and the fan motor.  The spin on hydraulic filter filters lower pressure oil coming out of the fan motor going back to the hydraulic oil tank.  Personally, I'd keep both filters.

[96 EVO]

18 minutes ago, Frank McElroy said:

Keep in mind that Monaco had a recommendation to change out AW-46 to ATF fluid in cold climate applications - we're talking temps below 32 DF.  This is because the high viscosity AW-46 was blowing out the oil cooler especially when temps got into single digits.

Also, look at the hydraulic system layout.  On my 2008 Dynasty, the single internal tank filter filters all oil going to the hydraulic pump that feeds both the steering gear box and the fan motor.  The spin on hydraulic filter filters lower pressure oil coming out of the fan motor going back to the hydraulic oil tank.  Personally, I'd keep both filters.

So, the spin-on isn't filtering return oil from the steering box?

[Frank McElroy]

4 minutes ago, 96 EVO said:

So, the spin-on isn't filtering return oil from the steering box?

That is correct on my coach.

[96 EVO]

Good to know!

I'm sure it would eventually reach that filter, but now I know that, I'll keep the internal.

[Pduggs]

4 hours ago, 96 EVO said:

You never know, the original owner of Paul's Dyn may have read the owners manual and replaced the factory installed ATF with AW-46.

My manual says AW-46, but it isn't!

Based on what I’ve seen, I don’t believe the original owner ever touched the hydraulic filter or changed the fluid. 

[Steve Merritt]

10 hours ago, jacwjames said:

Hard to tell but the oil looks dark. 

I'd consider getting an oil analysis. 

my coach had and was drained and refilled with Castrol Blue hydraulic fluid

[jacwjames]

3 minutes ago, Steve Merritt said:

my coach had and was drained and refilled with Castrol Blue hydraulic fluid

Well, that explains the darker color 🤑

[Steve Merritt]

1 hour ago, Steve Merritt said:

my coach had and was drained and refilled with Castrol Blue hydraulic fluid

I appreciate all of the concern about the color of the fluid but it is actually a very light blue if you look at the picture very closely look to the right of the filter and about one inch down from the zipper on the top of the bag and you will see a light blue smudge about the size of a peanut shell that is the clean fluid. The fluid washed all the dust off of the filter when it ran down the side of the filter as I was removing it and there was a lot of dirt that was on the rubber seal when it fell off in the bag also. I was so focused on the red cone I never gave a thougt about the "dirty" fluid in the bottom of the bag but the fluid I assure you is super clean. The filter is really large and trying to make it spin inside of a zip-lock bag while covered in fluid is not easy and impossible to keep clean.

[96 EVO]

32 minutes ago, Steve Merritt said:

  The filter is really large and trying to make it spin inside of a zip-lock bag while covered in fluid is not easy and impossible to keep clean.

Yep, but it sure works at preventing a mess!

[amphi_sc]

On 5/25/2023 at 9:05 AM, Tom Cherry said:

Not a bad idea…..but the other option, assuming no major contamination, is to drain (syphon out or pump) the reservoir and replenish with Transynd or the Mobil Delvac equivalent.  However, some knowledge folks that have the “we NEVER used hydraulic fluid (oil) after 2006” DID from the factory, have the AW46 and don’t have the 3 filter reservoir, only the one and NO pressure filter…. They are content to rock on….

If you start the conversion…..do it again in 3 years….and will bd fine….per TRW…

.

Tom, are you saying it is okay to mix Transynd into the AW46?  I don't think I would get all the existing AW46 out of the lines, pump, etc by sticking a hose into my reservoir, so the Transynd would wind up being mixed with the residual AW46. In the past when I changed the big external filter I topped off the light brown fluid with AW46.  If it is okay to mix fluids, then I guess I could leave the spare gallon of AW46 at home as I also carry a spare gallon of Transynd in case the Allison needs some on a trip.  I seem to have a large spin on filter and pop up pressure "gauge" on the left and about a two gallon reservoir on the right with no way of getting into the tank other than the small dipstick (or removing lines).

[Tom Cherry]

1 hour ago, amphi_sc said:

Tom, are you saying it is okay to mix Transynd into the AW46?  I don't think I would get all the existing AW46 out of the lines, pump, etc by sticking a hose into my reservoir, so the Transynd would wind up being mixed with the residual AW46. In the past when I changed the big external filter I topped off the light brown fluid with AW46.  If it is okay to mix fluids, then I guess I could leave the spare gallon of AW46 at home as I also carry a spare gallon of Transynd in case the Allison needs some on a trip.  I seem to have a large spin on filter and pop up pressure "gauge" on the left and about a two gallon reservoir on the right with no way of getting into the tank other than the small dipstick (or removing lines).

TRW said that.  It is often done….not what the scientists and engineers condone….but it works.  Contamination due to water and metallic fines and such is more of an issue.  In all fairness, i was responsible for over 200 molding snd casting machines at two different jobs.  The secret of our up time as well as reduced maintenance cost was PM.  We had rotating filters, constructed specifically where they could be moved from machine to machine and we pumped the hydraulic reservoir on each machine for a period of time….and we changed the filters in the recirculating units.  The zinc and aluminum casting machines ran upwards to 1200 dF.  The plastic injection molding machines were much lower in the 300 dF range or so.  Failure of the critical valving was the issue….as well as the pumps and cylinder seals.  So, I have a little insight.

As to your system, it is the same as mine.  YES.  If you want to break the front steering gear connections and also the CAC and pump lines, you can drain it.  One can use shop air, dried of course, to accelerated the purge….much like the first step in winterizing.

Then refill with a synthetic (Transynd or Delvac or TES 295) ATF.  As to what i did.  Each time I had a drill pump and a “suction” pump (a large commercial caulking sized cylinder and you used it like a hypodermic syringe). I am NOT one to break lines unless necessary.  Then I prefilled the spin on and the reservoir.  The first step, whether you convert or change the reservoir filter is to loosen the band clamp.  Pop the top.  Measure down from the lip of the reservoir…..that is where you refill to…. You need to look on the back side of the tank, assuming it is like mine.  The bolt loosens a band clamp (commonly used for such or large chemical drums).  

So that’s it.  If you do NOT intend to store or use your MH In temperatures down to zero, you probably ARE OK.  Just be aware that there is a viscosity change and when the AW 46 is near zero (dF), it has expanded and when you start the pump….then it has (many times reported here) increased in pressure and damaged things. See the screen dump from a paper on choosing hydraulic oils for use in timber harvesting (Shearing trees and moving large logs). 

i THINK that if you don’t operate the system and it gets “cold”, there is not an issue.  But, some folks do use their rigs in near zero conditions….

All a matter of what you do.  Continue to use, but change (my opinion) the AW 46….but the frequency of such is may less with AFT or even less with Transynd….that is why i doubt i will ever drain it again…..the concentration of the Transynd is enough now….after two refillings.

[amphi_sc]

Thanks Tom.  Good to know.  We might very rarely hit low teens, rarely upper single digits but if it's that cold we are staying put and not driving.  Might rarely be driving in mid 20's.  Typically we're fair weather folks staying in the warmer climates.  Think I will keep the AW46 for now rather than replace, but have noted the low temp caution to keep in mind.  Thanks again.