Hydraulic system very very slow

[John C]

My 2007 Monaco Dynasty hydraulic system is very very slow, that include 3 room slide out and generator slide out, one electric slide out is much fast than the hydraulic one.
I am plugged in to shore power and just change the hydraulic filter and replace all hydraulic oil, the hydraulic oil is full.

I don't have level jack.

Any idea where to look?

Thanks!

[Ivan K]

I would guess that under the steps you would have a reservoir for the slideouts. Have you checked there?

[Frank McElroy]

38 minutes ago, John C said:

My 2007 Monaco Dynasty hydraulic system is very very slow, that include 3 room slide out and generator slide out, one electric slide out is much fast than the hydraulic one.
I am plugged in to shore power and just change the hydraulic filter and replace all hydraulic oil, the hydraulic oil is full.

I don't have level jack.

Any idea where to look?

Thanks!

Even though you are plugged in have you checked your chassis battery voltage.  I believe your hydraulic pump is working off your chassis batteries and if your Big Boy is not working properly, your chassis batteries could be low.

[John C]

2 minutes ago, Ivan K said:

I would guess that under the steps you would have a reservoir for the slideouts. Have you checked there?

Just slipped under the coach and checked, unfortunately no reservoir.

 

[Ivylog]

Hydraulic system for the slide’s doesn’t have a filter… located under the steps. It’s 12V motor may not have a full 12V. I’d start there.

Under one of the steps you should have a plastic bin. Remove it and check from above.

[John C]

8 minutes ago, Frank McElroy said:

Even though you are plugged in have you checked your chassis battery voltage.  I believe your hydraulic pump is working off your chassis batteries and if your Big Boy is not working properly, your chassis batteries could be low.

Just checked, the chassis battery is 13.69V, the house battery is 13.9V.

12 minutes ago, Ivylog said:

Hydraulic system for the slide’s doesn’t have a filter… located under the steps. It’s 12V motor may not have a full 12V. I’d start there.

Under one of the steps you should have a plastic bin. Remove it and check from above.

checked again, no plastic bin, just the step motor.

[vito.a]

John, you should understand you have more than one hydraulic system.  The one in the engine compartment runs the power steering and hydraulic cooling fan.  

The system under your step runs three of the slideouts and the generator slide.  If your chassis battery (two engine start Group 31 batteries) is not being charged through the Intellitec Big Boy solenoid the voltage is low and your 12v electric hydraulic pump is running slow.  Also, the Intellitec Big Boy is famous for corrosion buildup on the copper contacts.  

Good luck!

[Frank McElroy]

Lift the hinged second step - there should be a plastic bin to unscrew

[Tom Cherry]

John….back to basics..  When you checked the batteries, that is NOT the correct voltage.  The 13.X means that the MH is plugged in and the inverter is charging and your Big Boy is working.  What you need to do is to unplug from shore (or Genny) and disconnect the solar (go to the controller and remove the positive leads from Battery 1 & Battery 2).  Then..TURN on a few exhaust fans as well as maybe some lights and run the water pump.  You should see the voltage drop down on the House to the high 12.7 or so.  NEXT, On the chassis, turn on the ignition and run the HVAC (Front system) on HIGH and also raise and lower a front shade or two.

SAME DEAL.  Knock off the surface charge.  NOW RECORD THAT.

NOW….  Locate the hydraulic motor….Frank has told you where to find the unit.  You need to put your VOM Probes on the motor terminals.  Then have someone extend or retract a slide and watch the voltage.  Make a mental note of the initial movement….then the “constant” voltage as the slide moves.

Slow hydraulic slides are a sign of a high resistance connection. If the voltage is dropping down into the mid to low 11’s, then that is the issue….and the solenoid could be the issue or an upstream probem.

NOW….Take a Jumper cable and jumper the positives on the House to the Chassis.  Repeat your experiment.  ODDS ARE…if you have a voltage drop, then the second set of batteries will help.

I have failing House Disconnect Switch….my slides are hydraulic and run off the House.  I can see a half volt drop across the house disconnect switch.  It took me years to “catch” the switch when the contacts were not properly connected. I installed a selector switch on my hydraulics and can run them from the House or Chassis or Both.  When the House switch “vibrates” and has the voltage drop (only half a volt), there is a significant drop in the slide movement or velocity or speed as compared to using the chassis bank.

ODDS ARE…if the motor is OK, then a failed solenoid or a faulty connection from the Chassis bank on forward is the cause. You can ONLY trace it down by running the slides in or out and measuring at every connection….very frustrating…but that’s the reality ….

[RWHenhouse]

Your hydraulic pump and reservoir are likely more towards the front of the coach, passenger side, just below the AC condenser fan.  Lots of hydraulic hoses and running to it.  Tough to miss.

[Donflem]

John here are pictures of my 2007 Dynasty steps with plastic bin I would think you have the same setup.

Don

[RWHenhouse]

I stand corrected!  My coach is a 2004 Safari Panther with the Cat 505HP.  I assumed the Dynasty would have the same chassis, looks like they made a change, or mine is more of an Executive with a different name.

[John C]

23 hours ago, vito.a said:

John, you should understand you have more than one hydraulic system.  The one in the engine compartment runs the power steering and hydraulic cooling fan.  

The system under your step runs three of the slideouts and the generator slide.  If your chassis battery (two engine start Group 31 batteries) is not being charged through the Intellitec Big Boy solenoid the voltage is low and your 12v electric hydraulic pump is running slow.  Also, the Intellitec Big Boy is famous for corrosion buildup on the copper contacts.  

Good luck!

Maybe mine is locate in a different place? please see attached pictures, under my step doesn't have anything?

23 hours ago, Frank McElroy said:

Lift the hinged second step - there should be a plastic bin to unscrew

Unfortunately under my steps is nothing, is it possible the previous owner relocated it?

OPPS! My bad!

I didn't realize it was the second step inside!

Now I got it, so what else should I try beside filling the reservoir?

Thank all of you so much!

[vito.a]

For your slide out hydraulic system look under the inside step.  The lid raises up.  

Also look at page 171 in your owner's manual.  It has a nice diagram of the slide out hydraulic pump and reservoir. 

It says:  Access the slide room hydraulic pump in generator compartment (curbside) at front of the motorhome 
behind the firewall.

Regardless, you really need to check your chassis battery voltage level unplugged without the charger running.  I suspect you have low CHASSIS batteries. 

Then check the Intellitec Big Boy solenoid back in the engine compartment.  It's under the plexiglass cover to the right of the engine.  The Big Boy combines the house and chassis batteries after the house batteries reach a preset voltage (assuming your Inverter is set up for charging correctly).   This charges the chassis battery.  

The problem is the copper contacts inside the Big Boy get carbon build up and do not make contact.  As a result, many of our chassis batteries get low.  

Edited March 7 by vito.a

[RWHenhouse]

Did you take a look under the front of the coach?  Or, locate one of the hydraulic hoses on your generator slide cylinder and follow it back to the pump/manifold.  As always, don't crawl under there without proper blocking to prevent the coach from crushing you if the air suspension fails.

Disregard my last post.  I think your last picture shows the pump manifold, that hex cap is likely the oil fill/check.

[John C]

3 minutes ago, vito.a said:

For your slide out hydraulic system look under the inside step.  The lid raises up.  

Also look at page 171 in your owner's manual.  It has a nice diagram of the slide out hydraulic pump and reservoir. 

It says:  Access the slide room hydraulic pump in generator compartment (curbside) at front of the motorhome 
behind the firewall.

Regardless, you really need to check your chassis battery voltage level unplugged without the charger running.  I suspect you have low CHASSIS batteries. 

Then check the Intellitec Big Boy solenoid back in the engine compartment.  It's under the plexiglass cover to the right of the engine.  The Big Boy combines the house and chassis batteries after the house batteries reach a preset voltage (assuming your Inverter is set up for charging correctly).   This charges the chassis battery.  

The problem is the copper contacts inside the Big Boy get carbon build up and do not make contact.  As a result, many of our chassis batteries get low.  

Yes, I got it. I thought it was outside step

I did voltage of the chassis batteries and house batteries when DW extending and retracting the slide

chassis battery : 12.78

House battery: 13.37

I will run the slide without plugged in tomorrow.

2007 Dynasty manual is different, I could not find anything talk about the hydraulic system under the step...

I assume under the hoses is the motor? lots of dirt and grease there, I will clean it up tomorrow and try to test the voltage of the motor.

Thanks.

Does that seems to be normally when slide was running?

[Tom Cherry]

9 hours ago, John C said:

Yes, I got it. I thought it was outside step

I did voltage of the chassis batteries and house batteries when DW extending and retracting the slide

chassis battery : 12.78

House battery: 13.37

I will run the slide without plugged in tomorrow.

2007 Dynasty manual is different, I could not find anything talk about the hydraulic system under the step...

I assume under the hoses is the motor? lots of dirt and grease there, I will clean it up tomorrow and try to test the voltage of the motor.

Thanks.

Does that seems to be normally when slide was running?

John,

Please read my previous post.  You need to unplug from shore. You need to then do a quick voltage drain to knock off the surface charge of each battery.  The Big Boy will be disengaged then.

Then measure the voltages of each bank....  DO NOT RUN THE SLIDES YET.  Once you know the voltages of the banks, then you can go from there. What you have shown is that your chassis battery is dropping.  How much, we don't know as the Inverter, with power plugged in, is STILL charging.  But that charge is not enough to keep them high enough for the motor to operate.

Once the surface charge is knocked off...., then you need to measure the voltage on the HYDRAULIC MOTOR. That is the KEY HERE.  We have to KNOW WHAT THE MOTOR IS SEEING. I suspect it is low...but you need to measure the voltage there, while the motor is running.....and then compare it to what the CHASSIS Battery was reading.

Do that and report back...one step at a time.

[John C]

Looks like the hydraulic tank for the slides is almost empty, I fill 3/4 a gallon of oil(that is all I have now), it is still not full, and it is MUCH MUCH faster now.

I will buy another gallon to fill it up to 100%.

I used engine cleaner to clean the tank and cylinders and wipe it out with paper tower, much better now but still a lot of grease there, It will probably take metal scrubber to make it really clean. But it is good for now

Thank your guys so much for all your help!

I really appreciate it!

 

[Chargerman]

Considering how much oil and grime that you have on the unit and how low the oil was it seems like you have a leak. I would clean it real good and then have someone actuate each slide one at a time in each direction while you observe the unit. The only way the unit should be low on fluid is due to a leak somewhere.

[John C]

3 minutes ago, Chargerman said:

Considering how much oil and grime that you have on the unit and how low the oil was it seems like you have a leak. I would clean it real good and then have someone actuate each slide one at a time in each direction while you observe the unit. The only way the unit should be low on fluid is due to a leak somewhere.

Good point. 

I will definitely do that.

Thank you 

[Rico K 2005 Knight]

On 3/5/2024 at 8:39 PM, John C said:

My 2007 Monaco Dynasty hydraulic system is very very slow, that include 3 room slide out and generator slide out, one electric slide out is much fast than the hydraulic one.
I am plugged in to shore power and just change the hydraulic filter and replace all hydraulic oil, the hydraulic oil is full.

I don't have level jack.

Any idea where to look?

Thanks!

If all hydraulics are slow and you changed the filter and oil then I would have someone with a flow meter check the condition of the pump. It sounds like it may be the pump or a the relief valve.

Good luck and please keep us posted. Cheers.

1 minute ago, Rico K 2005 Knight said:

If all hydraulics are slow and you changed the filter and oil then I would have someone with a flow meter check the condition of the pump. It sounds like it may be the pump or a the relief valve.

Good luck and please keep us posted. Cheers.

You may be able to remove the return line to the tank and check to see if oil is flowing back through that hose to the tank when requesting a slide to open. You shouldn't have flow through the return line unless the slide is closing. That can also let you know if you have a relief issue. 

[Paul J A]

On 3/7/2024 at 1:05 PM, John C said:

Looks like the hydraulic tank for the slides is almost empty, I fill 3/4 a gallon of oil(that is all I have now), it is still not full, and it is MUCH MUCH faster now.

I will buy another gallon to fill it up to 100%.

I used engine cleaner to clean the tank and cylinders and wipe it out with paper tower, much better now but still a lot of grease there, It will probably take metal scrubber to make it really clean. But it is good for now

Thank your guys so much for all your help!

I really appreciate it!

 

Clean up that area with Boeshield T 9

[Chargerman]

Hmm. Boeshield is a protectant. I use it for things at the shore to protect from corrosion. I would thing a degreaser would be much more productive  

[John C]

On 3/8/2024 at 4:46 AM, Rico K 2005 Knight said:

If all hydraulics are slow and you changed the filter and oil then I would have someone with a flow meter check the condition of the pump. It sounds like it may be the pump or a the relief valve.

Good luck and please keep us posted. Cheers.

You may be able to remove the return line to the tank and check to see if oil is flowing back through that hose to the tank when requesting a slide to open. You shouldn't have flow through the return line unless the slide is closing. That can also let you know if you have a relief issue. 

It is very fast now after I add about 1 1/2 gallon of oil.

where is the return line? how do you check the return line? disconnect to see if there are oil come from the line?

[Ivan K]

There's no dedicated return line, the lines switch function as the slide goes in or out.