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Topic: Leaking pump on CAT 3116 (Read 622 times) previous topic - next topic

Leaking pump on CAT 3116

The leak came with the coach, I posted about it in 2016, but it got no worse. NOW, it's worse!! On feeling underneath the belt, I get clean oil drips. Is this the power steering pump, or? I see some files of Brett's and the later PO, but not sure which is which? Once I know what is what, I'll research what I need; hopefully not a fresh pump! Thanks, all!  ^.^d
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Leaking pump on CAT 3116

Reply #1 –
Mike, I doubt you have the tools to put in the seal. It is not a major job for someone to pull the pulley and remove-replace the seal. I had to remove the pulley on my '81 to get the seal number on a similar pump. If you can get the seal number ahead of time it would be less than  a one hour job.
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: Leaking pump on CAT 3116

Reply #2 –
Quote from: craneman –
Mike, I doubt you have the tools to put in the seal. It is not a major job for someone to pull the pulley and remove-replace the seal. I had to remove the pulley on my '81 to get the seal number on a similar pump. If you can get the seal number ahead of time it would be less than  a one hour job.
Thanx, Craneium, I don't have the tools, and with a fused back, am not going to attempt it. Are we on the same page? Is what's called a 'power steering pump' and a 'hydraulic pump' one and the same? Here's what I got from Brett:
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Leaking pump on CAT 3116

Reply #3 –
They are one and the same on most coaches. If you only have one pump then they are the same.
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: Leaking pump on CAT 3116

Reply #4 –
Mike,

That entry by Brett says "hydraulic fan pump and fan motor".  Pretty specific reference to what that pump powers.  But, like Chuck (craneman) says, if that is the only pump on your coach, then it probably does double duty as cooling fan pump and power steering pump.

Do you only have one oil reservoir (fluid tank)?

On our Cummins 8.3L there are two hydraulic pumps, and two hydraulic reservoirs.  One pump is for the cooling fans, and one is for the power steering.  Two completely separate systems.  Looking at the engine, I can easily see the cooling fan pump, but the power steering pump is totally hidden from sight.  If I didn't have two oil reservoirs I would never guess the second pump is there.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Leaking pump on CAT 3116

Reply #5 –
Mike,

Determine whether it is the main seal, a hose connection, etc.

Then, you might contact a local hydraulic shop with the Make/model to see if they can help.

As you noted, the pump was installed new from Foretravel August 2004..
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: Leaking pump on CAT 3116

Reply #6 –
So does Mike's Cat only have one hydraulic pump?
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Leaking pump on CAT 3116

Reply #7 –
Quote from: Chuck & Jeannie –
So does Mike's Cat only have one hydraulic pump?

Chuck,

Good question.  But since last time I worked on it (other than filter and fluid changes) was 15 years ago, this is only my  recollection:

As I recall, that is the cooling fan ONLY pump with the power steering being driven off the "back" of the air compressor.

Should be very easy to follow the hoses to verify.
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: Leaking pump on CAT 3116

Reply #8 –
Quote from: wolfe10 –
...that is the cooling fan ONLY pump with the power steering being driven off the "back" of the air compressor.
That is exactly the way our Cummins is set up, but I don't know anything about Cat engines.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Leaking pump on CAT 3116

Reply #9 –
Where would the reservoir for the power steering be if it is separate?
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: Leaking pump on CAT 3116

Reply #10 –
Quote from: craneman –
Where would the reservoir for the power steering be if it is separate?
On my coach there is one reservoir on each side of the engine access opening.  Standing behind coach looking at engine - look left and there is the hydraulic fan pump reservoir.  Slightly to the right of the opening is the power steering pump reservoir.  Both my tanks look similar to the one in Mike's photo, with a removable dipstick to check oil level.  Fan pump reservoir is larger - holds more oil.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Leaking pump on CAT 3116

Reply #11 –
Our '95 U240 has a single pump that has 2 sections.  One part is the PS side that uses a small tank similar the Mike's picture.  The hydraulic fans are run by the other section and use a large tank that hangs on the right side.
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon

Re: Leaking pump on CAT 3116

Reply #12 –
Quote from: Dave Larsen –
Our '95 U240 has a single pump that has 2 sections.  One part is the PS side that uses a small tank similar the Mike's picture.  The hydraulic fans are run by the other section and use a large tank that hangs on the right side.
So it looks like I've got to do more research on WHAT is leaking? It's just below the black pully.
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'
 

Re: Leaking pump on CAT 3116

Reply #13 –
The 1993 U240 (Mike's coach) has two hydraulic reservoirs-- two different diameter/volume reservoirs. PS is the smaller, Fan the larger.
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