CAT 3116 – raw water pump change/ replacement help

[Boca_Vincent]

Hello all. Last weekend I did my oil & filter changes and after running engines, I have what is now a significant drip from the port engine water pump. After my last impellor change on this unit I was getting a very small drop every few minutes. It seemed minor (to me), so I let it go, but did purchase the new pump to have at the ready. The now constant drip is coming from the center of the unit, so I am assuming it is the seals.
I brought the new pump home with me to get painted. Looking at the pump, I see there is a threaded shaft for connecting to the engine. I did some searching here but can’t find any details on how I go about the removal and installation of the new pump. I am hoping some of you may be able to share the procedure with me, or if there is a diagram out there that I am not aware of.
My quick inexperienced observation is that I would need to disconnect the hoses, then remove the hose connector plates to reinstall on the new unit. The bottom bolt of the pump looks fairly tight to the engine mount. I am racking my brain over that shaft… my old cummins had round bevel type gear that just got lined up and bolted on, so I have no idea here.

Your insight and tips on making this as painless as possible are appreciated.

 

[dtfeld]

When you remove the old pump, there will be a gear on that shaft. You will need to get a gear puller and pop the old gear off, and transfer to the new pump. You can buy another set of gears, but last I checked, the gears were several hundred $$ apiece.

Use a torque wrench or impact wrench to make sure the nut is tight, and I used a punch to lightly Nick the thread to ensure the nut/gear stayed in place.

 

[Strecker25]

When you remove the old pump, there will be a gear on that shaft. You will need to get a gear puller and pop the old gear off, and transfer to the new pump. You can buy another set of gears, but last I checked, the gears were several hundred $$ apiece.

Use a torque wrench or impact wrench to make sure the nut is tight, and I used a punch to lightly Nick the thread to ensure the nut/gear stayed in place.

Like Dave said, swap the gears. I didn't have a press so I removed the nut, put the gear in a vice with padded jaws, and smacked the center shaft with a mallet and the gear popped off. It's just a taper fit so a little shock should get it loose.

 

[dtfeld]

Like Dave said, swap the gears. I didn't have a press so I removed the nut, put the gear in a vice with padded jaws, and smacked the center shaft with a mallet and the gear popped off. It's just a taper fit so a little shock should get it loose.

Oa little heat on the gear/ ice on the shaft to help it pop loose.

 

[Boca_Vincent]

OK, so I went down on Sunday to attempt removal. I say attempt because I came home empty handed.
I have the top hose off entirely, and the 2 main thru bolts that connect the pump body are out. The bottom hose is loosened, but I can only get to one of the hose flange connector bolts (circled in red). I have the pump body separated about a half to 3/4 inch but this still does not allow me enough clearance to get it out.
On the bottom raw water intake, am I supposed to disconnect the 2 fittings (blue circled) and the support bracket for that section. (sorry - not sure of the name of that part). One of those is a hard line so no movement there with out taking it off. I just want to make sure before I go taking unnecessary steps. Also note - the pic is from starboard side, only one I could find at the moment. I am actually working on the port side. Thanks.

 

[Riptide III]

I have found it easiest if:
1 loosen hose clamp on upper green hose.
2 loosen both clamps on lower green hose.
3 slide lower hose off the fuel cooler aft over the pump. Yes I know it’s tight but it will slide up around the bend.
4 remove 2 yellow bolts and nuts on cooler mount this allows you to move it forward slightly giving you room. Don’t remove fuel hoses
5 remove 2 red nuts and bolts.
The entire unit will now be removed from the engine. Replace impeller while on the bench. You need to replace the metal seal between housing and engine

 

[Boca_Vincent]

Thanks Rip. That was other question I had - if I could clean and reuse the plate seal. I will go order one now. Guessing I will need the #13 part O-ring as well.

As for your sequence. I will work on getting the lower hose up the elbow. I have both clamps loosened up, but didn't get much lateral movement.
I'll undo the cooler mount bracket- this seems tricky to do with the fuel hoses in place.
The 2 red bolts are out. that was the easy part.
The new unit has an impeller already installed. I should just need to switch the gear after getting it out.
Appreciate all the help so far.

 

[Riptide III]

Typical Raw water impeller replacement
7E-0321 impeller
8T 2944 o ring for impeller plate
135 9819 seal for pump. Metal

 

[Boca_Vincent]

I went down to the boat after work yesterday and got the pump off.
There was no way to get that lower green hose up the elbow any further. But loosening the clamps on the cooler mount did allow for just enough movement back to get the needed clearance.
Have the pump on the bench now. Definitely well past its life.. but the impeller with about 200 hours on it is in great shape. The top nut came right off. I put a puller on it and jammed a screwdriver in the bottom to hold the shaft, but she still wouldn't pop off. I had to call it and head to dinner so tonight I'll try Dave and Ryan's other tricks.

 

[techmitch]

I went down to the boat after work yesterday and got the pump off.
There was no way to get that lower green hose up the elbow any further. But loosening the clamps on the cooler mount did allow for just enough movement back to get the needed clearance.
Have the pump on the bench now. Definitely well past its life.. but the impeller with about 200 hours on it is in great shape. The top nut came right off. I put a puller on it and jammed a screwdriver in the bottom to hold the shaft, but she still wouldn't pop off. I had to call it and head to dinner so tonight I'll try Dave and Ryan's other tricks.
View attachment 146083

Smack the press bolt with a hammer, tighten some more and smack it again.

 

[Risingson]

Smack the press bolt with a hammer, tighten some more and smack it again.

Just make sure the gear is in the exact same position on the new pump when you press the gear onto the new pump.
I measured it in MM

 

[Boca_Vincent]

Thank you as well RS and Mitch. I took a caliper measurement beforehand. A few more cranks on the puller and she popped. New pump needed another coat of paint so I don't have it back on yet.
Also, have some rust on the engine mount and oil pan from the leak that I need to address first.
While the gear is exposed, should I grease or do anything else besides a surface cleaning?

 

[dtfeld]

Thank you as well RS and Mitch. I took a caliper measurement beforehand. A few more cranks on the puller and she popped. New pump needed another coat of paint so I don't have it back on yet.
Also, have some rust on the engine mount and oil pan from the leak that I need to address first.
While the gear is exposed, should I grease or do anything else besides a surface cleaning?

I believe that gear is engine oil lubricated, so no grease.

 

[Boca_Vincent]

Pump is back on. Did a quick run out and checked for leaks - everything looks good.
Thanks again for everyone's help.
One last thing...what to do with old one? Seems like a pretty hefty chunk of brass.

 

[ttmott]

Thank you as well RS and Mitch. I took a caliper measurement beforehand. A few more cranks on the puller and she popped. New pump needed another coat of paint so I don't have it back on yet.
Also, have some rust on the engine mount and oil pan from the leak that I need to address first.
While the gear is exposed, should I grease or do anything else besides a surface cleaning?

If the raw water hoses haven't ever been replaced then....

 

[Strecker25]

Pump is back on. Did a quick run out and checked for leaks - everything looks good.
Thanks again for everyone's help.
One last thing...what to do with old one? Seems like a pretty hefty chunk of brass.

some folks rebuild them, mine is sitting in the basement untouched. While having a 'spare' onboard sounds like a good idea I can't imagine doing this swap away from home port

 

[Risingson]

You should be able to send it to Cat or wherever you brought it for a core rebate. Mind was 285.00 back

 

[Boca_Vincent]

If the raw water hoses haven't ever been replaced then....

Yeah, that's on the list. Will break down the whole cooling circuit to clean the HEX and AC and do all hoses and clamps. Summer caught up to me too fast, hence why I just did the leaky pump.

some folks rebuild them, mine is sitting in the basement untouched. While having a 'spare' onboard sounds like a good idea I can't imagine doing this swap away from home port

Agreed. Job was more challenging than I thought. No point in carrying a spare.

You should be able to send it to Cat or wherever you brought it for a core rebate. Mind was 285.00 back

A core rebate is exactly what I was wondering about. I bought it from Marine Pump Direct. I don't see anything regarding cores on there but I will ask.

Thanks.