What's new

Cat 310 - Water in the Oil

Bubbles Galore

Active member
Joined
Apr 11, 2008
Messages
2,115
Reaction score
0
Points
36
Location
Michigan
First time I've run into this problem before. I'm usually pretty good at maintaining my pumps, so I'm a bit dismayed. What would cause this? Low pressure seals going bad? I'm not sure what is going on...thoughts?
 

cantbreak80

Maybe I need new clubs
Joined
Feb 10, 2008
Messages
1,131
Reaction score
582
Points
113
Location
CO
Most likely...
1 Cracked plunger
2 Plunger retainer bolt o-ring split
 

Bubbles Galore

Active member
Joined
Apr 11, 2008
Messages
2,115
Reaction score
0
Points
36
Location
Michigan
Thanks, I will check it out tomorrow and see what it looks like...any tips or tricks for checking out the plungers?
 

MEP001

Well-known member
Joined
Aug 30, 2007
Messages
16,665
Reaction score
3,946
Points
113
Location
Texas
It's highly unlikely to be a cracked plunger on a 310, but I've seen it happen. It's almost certain to be a plunger bolt seal. I'd recommend replacing the copper washer, o-ring and backup ring on all three bolts. I've seen used plungers listed on Kleen-Rite's site, might be good to have on hand when you pull the pump apart.
 

cantbreak80

Maybe I need new clubs
Joined
Feb 10, 2008
Messages
1,131
Reaction score
582
Points
113
Location
CO
A cracked plunger may not be obvious until you remove the retainer. Then, suddenly it comes off the crosshead in pieces.

Retainer o-ring and backup ring damage will be obvious as soon as they are exposed.

In either case the crosshead will be corroded and should be lightly polished with emory cloth or fine steel wool. (It will make reassembly easier)
 

MEP001

Well-known member
Joined
Aug 30, 2007
Messages
16,665
Reaction score
3,946
Points
113
Location
Texas
cantbreak80 said:
A cracked plunger may not be obvious until you remove the retainer. Then, suddenly it comes off the crosshead in pieces.

Retainer o-ring and backup ring damage will be obvious as soon as they are exposed.

In either case the crosshead will be corroded and should be lightly polished with emory cloth or fine steel wool. (It will make reassembly easier)
That's been my experience with General pumps too, but the piston on a Cat is stainless and doesn't corrode.
 

Kevin Reilly

self serve carwashes
Joined
Aug 31, 2007
Messages
203
Reaction score
0
Points
16
Location
Stockton, CA
Your Crank case oil seals should be replaced if you're getting water in the crank case. If your oil is milky white but NOT increasing in volume in the crank case then that would be from moisture in the room. Look @ the glass gauge on the back of the pump to see if the oil/water is above the red mark

If the oil is milky white and is above the red dot mark on the back of the pump then the crank case oil seals should be changed. A fun job.:eek:
 

MikeV

Member
Joined
Sep 18, 2007
Messages
435
Reaction score
2
Points
16
Location
Houston, TX
It is my understanding that the crankcase oil seals are there to keep the oil in, not to keep water out. Am I wrong about that? Seems to me that water is getting past the plungers.
 

MEP001

Well-known member
Joined
Aug 30, 2007
Messages
16,665
Reaction score
3,946
Points
113
Location
Texas
MikeV said:
It is my understanding that the crankcase oil seals are there to keep the oil in, not to keep water out. Am I wrong about that? Seems to me that water is getting past the plungers.
You're correct, but I agree it's a good idea to change the oil seals if a significant amount of water is in the oil or if it's been in the crankcase long. The oil seals have a spring wrapped around them which can rust and break, and it will leak oil if that happens. When I've serviced General pumps with water in the oil, I'd always change the oil seals along with the plunger seals. It's a bigger deal with a General since if it leaks oil you have to (or you're supposed to) replace the plunger bolts and washers too, making it a more expensive job later than just replacing the seals while you're down to them.
 

mjwalsh

6 bay SS w/laundromat
Joined
Sep 7, 2007
Messages
3,134
Reaction score
173
Points
63
Location
North Dakota
First time I've run into this problem before. I'm usually pretty good at maintaining my pumps, so I'm a bit dismayed. What would cause this? Low pressure seals going bad? I'm not sure what is going on...thoughts?
Bubbles,

This is highly unlikely to be the problem; but on our earlier Cat pumps before the Cat 310s ... the vent hole on the big red cap had tape over it that was supposed to be removed & was not. It actually caused the oil to get milky from water. It must have had been something to do with a vacuum created.

MikeW
 

Plow Guy

Member
Joined
May 19, 2008
Messages
67
Reaction score
0
Points
6
Location
Co Rocky Mnts
Rusty Stud.

Bubbles, The plunger stud may be rusty. Rap the plunger with black electrical tape. Use a pair of pliers, be gentle , work the plunger back and forth before you try to pull it off. When the tape rips, retape it. Take your time. I use plumber’s emery cloth on the stud to get the rust off. Don’t remove to much metal. When the studs are clean I spray them with CRC marine rust inhibiter. Use your fingers to cover the threaded holes. Use blue lock tight on the plunger retainer bolts. It is very IMPORTANT to use a torque wrench. If you over torque the bolts the plungers will crack. I can give you the spec. but go to the cat pump site. It will give you all the torque specs. One more thing, Harbor freight has a set of wire brushes that will clean the inside of the plungers. I highly recommend using them. I spray tri-flow inside the plungers to get a good real on the o-ring. Good luck, Pete
 

Kevin Reilly

self serve carwashes
Joined
Aug 31, 2007
Messages
203
Reaction score
0
Points
16
Location
Stockton, CA
Bubbles you haven't indicated whether the crankcase was full, or half full or 3/4 full with the sight glass. If it is still in the center of the red dot then that would be moisture and no reason to change the crankcase oil seals.

If it is above that mark then then it would be important to change them now rather than later because you have not solved your problem.

It is also important to follow the direction regarding oil in the 3 holes on the blue body of the pump. All that does is lubricate the Rod Plunger through the wicks underneath. The reason that you do this is evident = lubrication of a moving part. If this isn't done when it becomes necessary to open the pump at a later date it's a bear to pull things apart and you'll be replacing parts that you wouldn't normally have to.
 

mjwalsh

6 bay SS w/laundromat
Joined
Sep 7, 2007
Messages
3,134
Reaction score
173
Points
63
Location
North Dakota
Bubbles you haven't indicated whether the crankcase was full, or half full or 3/4 full with the sight glass. If it is still in the center of the red dot then that would be moisture and no reason to change the crankcase oil seals.

If it is above that mark then then it would be important to change them now rather than later because you have not solved your problem.

It is also important to follow the direction regarding oil in the 3 holes on the blue body of the pump. All that does is lubricate the Rod Plunger through the wicks underneath. The reason that you do this is evident = lubrication of a moving part. If this isn't done when it becomes necessary to open the pump at a later date it's a bear to pull things apart and you'll be replacing parts that you wouldn't normally have to.
Bubbles,

Ditto on what Kevin said. I remember being at a Detroit ICA Car Wash show in the early days of Cat Pump & the Cat booth person said that even though they had both the "Prrrmmm a lube" ... the version with the three oil holes were actually better. Kevin appears to have shed on light on some of the reasons why.

mike walsh king koin of bismarck
 

MEP001

Well-known member
Joined
Aug 30, 2007
Messages
16,665
Reaction score
3,946
Points
113
Location
Texas
mjwalsh said:
I remember being at a Detroit ICA Car Wash show in the early days of Cat Pump & the Cat booth person said that even though they had both the "Prrrmmm a lube" ... the version with the three oil holes were actually better.
The "Perm-a-Lube" seals are only found in PISTON pumps and are not in the 310 or any other plunger pump.

I have my doubts as to the usefulness of oiling the wicks considering the 310 and the 5cp use the exact same seals, and the latter doesn't have wicks at all.

Plow Guy may be right; the 5CP has a stainless bolt through the plunger, but the 310 must have a steel piston rod through it that can rust. If you've caught the leak early it shouldn't be a problem to get the plunger off. I would usually wrap a towel around the plunger and use Vice Grips to try and work it off, but with a General pump it was often so bad I'd just have to break it.
 

pcb

Leprechaun Car Wash
Joined
Nov 24, 2007
Messages
154
Reaction score
11
Points
18
Location
Dublin, Ga
They look just like the low and high pressure seals. When you pull the head off, you'll need to pull off the ceramic plungers and the oil seals will be behind them.
 

DiamondWash

Well-known member
Joined
Aug 31, 2007
Messages
2,373
Reaction score
478
Points
83
Location
Des Moines, Iowa
I have a 310 at another wash I'm assisting with that has water in the oil, does anybody know the part # fron KR I would need to order the "oil seals" for the 310 and is that the only seal kit I should replace?
 

cantbreak80

Maybe I need new clubs
Joined
Feb 10, 2008
Messages
1,131
Reaction score
582
Points
113
Location
CO
Steve,
Cat oil seal p/n is 43228.
However, they are accessed thru the crankcase which means you have to remove the head, plungers, and connecting rods...that means you also have to disassemble the entire back end of the pump to replace them.
So, you'll want...at minimum:
(2) 43343 bearing cover o-rings
(2) 43222 crankshaft oil seals
(1) 48773 rear cover o-ring

You may discover that water in oil is caused by a cracked plunger or a failed plunger retainer o-ring rather than the crankcase oil seals.
The crankcase oil seals keep the oil in the crankcase...they do not keep water out of the crankcase.
A failed plunger or retainer o-ring allows high pressure water to push past the garter spring/lip of the oil seals.

Here's the exploded view of the 310:
 

Starrwash

Member
Joined
Nov 24, 2018
Messages
83
Reaction score
27
Points
18
Location
Zumbrota Minnesota
It’s ok to buy a new pump considering parts and time and length of repair life. My thought. Simple seals fine, start digging to deep seems not cost or time efficient.
 
Top