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Topic: Hydraulic Fans and Power Steering Systems (Read 2693 times) previous topic - next topic

Re: Hydraulic Fans and Power Steering Systems

Reply #25 –
Update:
  I spoke with Mr. Blackman with FT today.  He has been out of town in training for  a while.  He is working on the info that I need about the hydraulic pressures and flow in my fan system.  I hope to hear from him again soon.

Pat,
Pat/Blue Angel
1995 U240 36ft
MC# 16511
Build# 4653

Re: Hydraulic Fans and Power Steering Systems

Reply #26 –
Update:  I have been working on getting the pressure and flow data for the hydraulic pump that runs a the fan motors.  A lot of the models FT built in this time period use the same pump.  This is what I have found:

Tag on pump:  25Aug08  80002642  Sauser/Danfoss
Model Code: DE2R-23PD-AA-104-10-N101-NNN-000-AU-AN-NNN
Example Decode:

DE2: D Series Cast Iron Gear Pump, Two Sections (Tandem)
The order code below provides an example of a two section (tandem)
pump.
A              B1 B2    C R    S D E F G H J
D E 2 R – 2 3 S H – B B – 1 0 4 – 1 3 – N 1 1 3 – N N N – 0 0 0 – A V – A C – N N N
Code Position Description
DE2R A D Series pump with two pumping sections, right hand rotation
23 B1 23 cm3 displacement on first section
SH B2 13 tooth spline input shaft
BB  C SAE B two bolt mounting flange
104 R 1 5/16-12 side inlet, 1 1/16 side outlet on first section
13 S 13 cm3 displacement on second section
N113 D No inlet and 7/8-14 side outlet on second section
NNN E No flow control setting
000 F No pressure control setting
AV G Assembly screws
AC H Standard Nameplate
NNN J No special features, black paint

It is a 2 section gear pump.  The front section is 1.37 CID and the rear section is 0.58 CID.  There are no flow control valves on the pump.  These are fixed displacement pumps, so they output flow is dependent on the pump RPM.  According to HydraQuip this pump max rpm is 3400.

(Pump RPM x 1.95 CID) / 231 = Pump GPM


I also found that the crankshaft pulley is for 85-95 chevy #14100594.
I would like to change the crank pulley to a larger diameter, not much just a little.  Any one got a different pulley number?  The number is on the inside face of the pulley.

Pat
Pat/Blue Angel
1995 U240 36ft
MC# 16511
Build# 4653

Re: Hydraulic Fans and Power Steering Systems

Reply #27 –
Pat,
  Just a thinking question. I understand pump Max rpm 3400, but what is the safe rpm of the fan motors and, or the plastic fan blades. By increasing the pump GPM  you possibly start building to much case drain pressure blowing motor seals.
    You might look at aftermarket aluminum pulleys for hot rods. Some have different OD sizes.
              Mark C.
1994 U280
Build #4451
"If everyone is thinking alike, then somebody isn't thinking"

Re: Hydraulic Fans and Power Steering Systems

Reply #28 –
Good Morning Mark,
  Good question and thanks for the response.  When I first started dealing with this issue back in June of 2014
My 95 U240 Fan Speed by Engine RPM where

Engine RPM            Fan 1(Front)   Fan 2(Rear)
  700            483/679      470/666
  1300            795/1093      785/1087
  2750            1620/2250   1600/2202

Foretravel Specs:
  Pump Output        1600PSI  @ 2750RPM
  Fan Speed High      2930RPM  @ 2750RPM
  Fan Speed Low      1900RPM  @ 2750RPM

I don't think there is a problem with fan speeds until they raise above 2930 RPM.  Mine are at 2200 RPM.  I am sure the fan motors will safely turn much faster than 3000 RPM, but I am like you what about the fan blades.  I just want to try a different pulley  combination, now both crank and pump are the same about 6".  I don't know how big a change to make?!?!

Pat,
Pat/Blue Angel
1995 U240 36ft
MC# 16511
Build# 4653

Re: Hydraulic Fans and Power Steering Systems

Reply #29 –
Pat,

Another option is to fit an auxiliary radiator up front.  "T" into the hoses to/from the heater core and use ball valves to direct flow.

Plenty of inexpensive car radiators out there. Shouldn't even need a fan, as you will not exceed normal engine temperature except when moving.  And, you are not paying engine HP to run the hydraulic fan faster.
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: Hydraulic Fans and Power Steering Systems

Reply #30 –
I wonder if there is enough room to replace the coolant hoses from the back to the front with 1 1/4" of hot water pex? That would reduce the friction loss and flow a lot more to the front radiators. Twice the interior diameter should give about 25% of the friction loss.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Hydraulic Fans and Power Steering Systems

Reply #31 –
Quote from: Pierce & Gaylie Stewart –
I wonder if there is enough room to replace the coolant hoses from the back to the front with 1 1/4" of hot water pex? That would reduce the friction loss and flow a lot more to the front radiators. Twice the interior diameter should give about 25% of the friction loss.

Pierce

Yes, should increase flow.  May be a lot less labor to install a small 12 VDC pump.
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: Hydraulic Fans and Power Steering Systems

Reply #32 –
Pat,
    From your inspection notes, it looks like you aren't getting high fan speed. If pump and motors good, you might have a pressure relive valve bypassing or your fan speed cartridge bypassing. You should be able to match Foretravels speed specs without modifications.
    Mark C.
1994 U280
Build #4451
"If everyone is thinking alike, then somebody isn't thinking"

Re: Hydraulic Fans and Power Steering Systems

Reply #33 –
Good Morning All,
  Brett: I have tried the front radiator and it does not work.  I will not be wasting engine HP to run the fans at proper RPM.

  Mark:  I control my hi/low fan speeds with a toggle switch on the dash.  I have changed all components (pump, motors, hi/low valve, pressure relief valve ).  The only original parts are the hoses. 

In 2014 I had ForeTravel work on it.  They changed the pump and the star value(pressure relief valve) with no change.  They sent me home saying it was the fan motors.  I changed them out with new ones from Italy($2500 just for motors.) with no change.  I originally had a John S. Barns Hydraulic pump.  FT changed it out with my current Sauser/Danfoss pump.  All other parts are the same as original.  Maybe the pump???  FT  does not have pressure(PSI) and flow(GPM) data, without that info you cannot dianoise the system.

I am thinking maybe the new pump needs to turn faster than the old one.  I do know that most of the FTs fan speeds are about 2700-3000RPM.  I know that on Chuck's 280 the pump pulley is smaller(5") than the crank pulley.  I am thinking about using a 5" pulley on the pump and removing my old 6.25" pulley, then check fan speeds.

Pat
Pat/Blue Angel
1995 U240 36ft
MC# 16511
Build# 4653

Re: Hydraulic Fans and Power Steering Systems

Reply #34 –
Quote from: wolfe10 –
Yes, should increase flow.  May be a lot less labor to install a small 12 VDC pump.
Don't know about all models but U300 have one installed down low on the left side by the engine. Andy's U300 had one that didn't work but either fixed or replaced it. Friction loss in a hose is like hull speed on a boat. Once you achieve a certain GPM, you need more ID to flow much more.

Pat, Brett and others have installed a front radiator with success. VW Vanagons, Porsche, others have only the front radiator and never have a problem cooling. The Vanagon even has a washer in the front to restrict the flow so there is more complete heat transfer up front.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Hydraulic Fans and Power Steering Systems

Reply #35 –

Pat,
    The system can be troubleshot.
1 If you are using original type motors, system pressure is 1600psi at high idle. This should be check at normal operating temperature.
2 Then it's a matter of GPM or flow. Sauer Danfoss should have a chart like the bus chart for the pump. It's to bad FT hasn't supplied this.
3 You are correct. Given your problems, you're thinking correct. Pulley size!
    I work on equipment every day. You need a very good 2000 psi gauge and I would recommend a flow meter. Might be able to rent one or find a mechanic with one. A 4-40 GPM should work. Something like this.
https://www.amazon.com/Hedland-H801A-075-Flowmeter
    Mark C.

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
1994 U280
Build #4451
"If everyone is thinking alike, then somebody isn't thinking"

Re: Hydraulic Fans and Power Steering Systems

Reply #36 –
Pat,
    Forget to mention. Pressure and flow to motors would have to be checked on high fan speed. The high - low soleniod causing oil to return to tank.
        Mark C.
1994 U280
Build #4451
"If everyone is thinking alike, then somebody isn't thinking"

Re: Hydraulic Fans and Power Steering Systems

Reply #37 –
Quote from: wolfe10 –
Pat,

Another option is to fit an auxiliary radiator up front.  "T" into the hoses to/from the heater core and use ball valves to direct flow.

Plenty of inexpensive car radiators out there. Shouldn't even need a fan, as you will not exceed normal engine temperature except when moving.  And, you are not paying engine HP to run the hydraulic fan faster.
That's a LOT of plumbing. The AC system does it, so it is doable.
1995 U-240 GrandVilla 36'
FMC# 18675
Lookingglass, OR
"There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." - Ed Howdershelt Abintra Press "If you have to lie to gain Support, you are not worth Supporting" "I just want to go somewhere where there's chocolate and nobody talks." - Ynez Reinschmidt

Re: Hydraulic Fans and Power Steering Systems

Reply #38 –
Quote from: Cpt_kludge –
That's a LOT of plumbing.

[/quote

You are using the existing hoses to/from the dash heater core.  No new hoses, just some valving in the nose to divert flow from heater core to radiator.
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: Hydraulic Fans and Power Steering Systems

Reply #39 –
Quote from: wolfe10 –
Quote from: Cpt_kludge –
That's a LOT of plumbing.

[/quote

You are using the existing hoses to/from the dash heater core.  No new hoses, just some valving in the nose to divert flow from heater core to radiator.

Kewl. I forgot about the Heater. Might be a good alternative.
1995 U-240 GrandVilla 36'
FMC# 18675
Lookingglass, OR
"There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." - Ed Howdershelt Abintra Press "If you have to lie to gain Support, you are not worth Supporting" "I just want to go somewhere where there's chocolate and nobody talks." - Ynez Reinschmidt