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Topic: Water pump leak Cummins C8.3 (Read 1398 times) previous topic - next topic

Water pump leak Cummins C8.3

On my pre-flight this morning noticed an antifreeze stain at water pump. Fluid level appeared normal, no sign of fresh leaking during warm up, ran down the road about 90 minutes, temps never over 180, coolant overflow level normal, but it appeared slightly more stained.

I would like to drive from Oregon to Albuquerque where I have an appointment at Statkus Engines for oil change on coach and generator along with a brake inspection in mid September. Do these seals blow out all at once, or can I manage this for the next month and 1,500 miles? I should have replaced the water pump when I did the thermostat and coolant two years ago. Sigh.


1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: Water pump leak Cummins C8.3

Reply #1 –
That is the weep hole to keep the coolant out of the engine oil. It will seep, then leak. The only advice I can give you is to take the belt off and rock the pulley up and down to make sure the bearing isn't failing. If the bearings are bad I would change it before a 1,500 mile trip.
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: Water pump leak Cummins C8.3

Reply #2 –
Yes, the coolant CAN become a massive leak. Had that happen to us on a ranch in the middle of nowhere S Texas.

But of you keep an eye on coolant level (in radiator, not just overflow reservoir) a couple of times a day, you can likely get where you are going.
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: Water pump leak Cummins C8.3

Reply #3 –
Do above but also get a water pump coming your going to need one.
Got to ask,are you driving all that way just for an oil change?
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Water pump leak Cummins C8.3

Reply #4 –
Actually, I would buy a new water pump and carry it with me.  EASY to replace if you have to.

Sure, if you can make it to your appointment that would be great. Good either way.
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: Water pump leak Cummins C8.3

Reply #5 –
I agree with Brett. Super easy change. Just a 1/2 drive ratchet or breaker bar for the belt and (3) 1/2" bolts. You will need some 5 gallon buckets to drain some coolant first and bring about 10 gallons of coolant/water to refill. Really is an easy job.

If nothing else having the water pump on hand and any service station could swap it.

Re: Water pump leak Cummins C8.3

Reply #6 –
I'm going to Albuquerque to see son. I have removed belt and checked for noise and play. Smooth, no play up or down or around. Cummins website lists part number 3804883 for my serial number, a Gates 42352hd crosses over to that number, short nose pump for C8,3.

I will call the Cummins dealer in Portland or Eugene to see if they can get one by Thursday. May try to get a Gates pump for "on the road" if can't get Cummins. I've got tools and means of capturing coolant if I have to change it out.

A lot of AG machinery used this engine, so that's another possibility.

Finding it tricky to keep coach rolling as full timer. I did a "stealth" grease job in the campsite earlier this week.

By the way, called FOT today for an appointment to replace a wardrobe door and another chore. We will be doing doctor appointments in NorthTexas in October. October was booked solid, got me in Nov 3 at mothership.


1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: Water pump leak Cummins C8.3

Reply #7 –
Don't forget the o-ring/seal may be a seperate part.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Water pump leak Cummins C8.3

Reply #8 –
Orielys may have a pump Patrick, that's where I got my last one for  8.3.... like mentioned above it's an easy fix. Biggest hassle is drain and refill coolant.
Dub McBride 1996 270

Re: Water pump leak Cummins C8.3

Reply #9 –
Quote from: John44 –
Don't forget the o-ring/seal may be a seperate part.
Those part numbers include an o ring. The Quickserve site has a good drawing that shows a replacement "kit" that includes o ring.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: Water pump leak Cummins C8.3

Reply #10 –
Water pump has been replaced by owner. The Quickserve part number (3804883) has been superseded by 5473302 which is also a kit that includes O ring  seal. The pump has a design change with the weep hole exiting from the base in a machined groove and a different impeller. Price was $230 which was comparable to a new Gates pump.

I drained the antifreeze into a 5 gallon bucket and then transferred it over to a large Rubbermaid storage box. I transferred about 2 gallons at a time. Replacement should have been straight forward. Remove serpentine belt, loosen alternator support bolts, remove the three bolts going into the block that hold the water pump in place.

After getting all the bolts out, the water pump would not budge. I used rubber hammer, Channel lock pliers on the pulley, a metal drift with steel hammer on the base edge, and a putty knife which I finally worked in to the top edge. I did not try heat because I didn't have any with me. I spent two hours or more working it loose with multiple applications of PB blaster.  I had to walk away from it a couple of times exhausted and in pure frustration.

 I wish I'd done this when I replaced the thermostat, which would be my advice to anyone replacing one or the other.

1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: Water pump leak Cummins C8.3

Reply #11 –
We put up with a weep hole leak for several years.  Seems like it would go for months in-between leaks.  Finally last Dec after another leak that was more than usual we took the rig to Cummins in El Paso.  Word of advice about Cummins.  Make sure they have the parts on hand before you schedule service.  It took the Cummins' mechanic all day to remove/replace the water pump and thermostat.  At first glance it looks easy, but it probably isn't.  Once the mechanic had the water pump assembly off the rig he told me there was nothing wrong with it except it had 120M+ miles on it.  I elected to replace it since I was already hip deep in time at that point.  Cost was ~ 2.4 coach bucks total.
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Water pump leak Cummins C8.3

Reply #12 –
2.4 sounds like a lot of cake but I've only done one on a 8.3 so I don't know the process on a m11. Cummins shop gets paid well don't they.
Dub McBride 1996 270

Re: Water pump leak Cummins C8.3

Reply #13 –
Sorry you had such a problem. Many would only use Cummins for chassis / power train issues, not RV problem. And often some fixes may be best done by oneself. There are a lot of RV issues that are best fixed by self or an RV shop.

Re: Water pump leak Cummins C8.3

Reply #14 –
I ran into significant problems with both the thermostat and water pump, both due to age. Stuff gets stuck after 20 years. I ended up having 30 or 60 hours invested since I also switched green coolant over to OAT. In theory the replacement should be easy since I have side radiator. It would help if I had fluid transfer equipment and on-site disposal of hazardous waste. Those time estimates don't include research, part ordering, pick up or disposal of waste. 

Working on these coaches is a lot like remodeling an old house. Only a genie can estimate how long it will take, especially the first time. It varies from one coach to the next and the experience level of the mechanic along with the equipment available for use. Depending which way the nut bounces after it falls from your arthritic fingers, you can lose an hour or day. These days I find myself adding 30 to 40 minutes to each job for first aid. My skin is getting thin.

I do like knowing how things work and fit together. But I hope I don't have to learn anything more for a while.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: Water pump leak Cummins C8.3

Reply #15 –
Quote from: Realmccoy –
These days I find myself adding 30 to 40 minutes to each job for first aid. My skin is getting thin.

I do like knowing how things work and fit together. But I hope I don't have to learn anything more for a while.

Got the same problem, working along suddenly realize I'm dripping blood. Forearms look like I've been trench fighting.
 These have been a godsend.  You can make them more form fitting with some velcro straps.  Soft leather around hands wears easily but has good feel. Slip a thin pair of mechanics gloves over when th fingers wear through.Get the ones with longest cowhide gauntlets.  Rose pruning gloves.

Amazon.com : rose pruning gloves


"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Water pump leak Cummins C8.3

Reply #16 –
There are some specialized types of Never Seez that can be used on exhaust manifold nuts and studs as well as various other nuts/bolts on the engine that will aid in future removal. Check first for the application.

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

Re: Water pump leak Cummins C8.3

Reply #17 –
You're not falling short on abilities Patrick, maybe physical because none of us are as agile as we were even 5 years ago. If a man counted the times it takes to go from your knees to your feet when changing 15 gallon capacity coolant system including the flush one would be surprised . It takes me and most of us twice as long to do what we used to but you got it done. We have to take more Tylenol at night but most of these youngsters won't even attempt what it takes to keep a rig running.
Dub McBride 1996 270

Re: Water pump leak Cummins C8.3

Reply #18 –
On my previous coach with a Cummins 8.3 I installed a NAPA rebuilt water pump in 2008. No issues with it for the following 8 years I owned it.  Two 5 gallon buckets to drain coolant below water pump level.  I was able to keep the coolant clean enough to put back in after replacing the water pump.

"Water pump repair notes for Cummins 8.3:

Couldn't get scheduled in with the local repair shop before my next relocation day, so I replaced the water pump today. I bought 2ea 5 gallon buckets and drained about 4 gallons coolant into each from the radiator petcock.

A 3/8 drive or extension bar relieves pressure on the serpentine belt to move it out of the way. A 13mm and a 10 mm socket to remove the 3 bolts holding the waterpump on. A convincer (pipe over ratchet) to break the waterpump loose off the block. Only a tiny bit of drainage from the pump/housing. Old pump was seeping from weep hole, some side movement on the pulley shaft, and bearings didn't sound so good either.

NAPA reconditioned pump looks the same as orig, $137, plus core charge $36, tax, 2 5 gal buckets, 1 gallon coolant, right about $200. I returned the core and have $36 back.  (2008 pricing).

I vented the system with the "T" fitting at top back of the block that the lines from the surge tank go to. I pulled the hose off the surge and refilled the original coolant back in from the hose until full there, then reattached "T" and surge hose to top up the surge tank. Lost about 1/2 gal (max) in the job, refilled from new coolant jug.

No leaks cool under no pressure, remains to be seen when I hit the road Thurs and reach op temp and pressure.

As a teenager, I had horrible experiences with reman waterpumps, and vowed only to buy new pumps since then. Sure hope this puppy works out, but I'm keeping the 5 gal buckets for a couple of weeks.

NAPA part no RW6077X .

(The reman pump worked out fine for the following years until 2016 when I sold the coach).

Dan - Full timing since 2009
2003 U320 40' Tag 2 slide