2007 Ski Nautique Circulating pump is leaking

[DocSki]

After starting up my boat today (on a lift with a hose attached to a FlushPro device) before skiing tomorrow, I noticed a leak that appears to be coming from the bottom of my circulating pump at the gasket interface with the engine. It is brisk dripping, but not quite a steady stream. I'm not really sure what the circulating pump does, but the engine temperature has been behaving normally. It rises to 158° as the boat warms up appropriately at idle, and it maintained that range under way and while skiing last week. Is this an immediate engine threat, or can I operate it and ski until I get the time and knowledge to fix it? How do I fix this?

[bturner]

Pictures are always helpful in particular here because people tend to misidentify or throw around terms universally for various components. By circulating pump I'm assuming you mean the cast pump mounted on the engine that on a car most would call the water pump and not the smaller raw water pump that typically has a hose going to a pickup in the hull bottom. The first I mention would look like this.....

https://skidim.com/pump-rw-5-7l-5-0l-serpentine.html

If this is indeed the pump you're referring to there's a good chance the water is coming out of a weep hole in the casting near the bearing of the pump. Water coming from here typically means that the bearing has or is failing and the pump would either need to be rebuilt or replaced. That said I've also seen the housing on these crack from freezing which produces a stream of water as well.

As to how soon it needs to be replaced..... IMO soon, very soon as it is what is circulating the water through the block. If it does fail significantly/completely and you don't catch it for whatever reason the engine will overheat which in turn could turn a relatively minor repair into something much bigger like say a head gasket. Or it could work well enough for some time before you have a significant failure. Typically when the bearing starts going you get a drip and notice a stain or wet streak under the pump. If you're seeing a stream from the weep hole I personally would think the failure is more advanced, but that's me. You or others may feel completely different about it.

As to how to fix it..... I watched my father rebuild these back in the 70s when I was a kid but we had access to a press and he was a truck mechanic in the Army and rebuilt stuff I never saw anyone else do. He also had a tendency of reusing gaskets and spending hours rebuilding things I would throw away. If he were helping me with a project I would destroy the old gaskets as they came off to make sure he used the new ones in the gasket kits that I had purchased. They had a completely different mentality of doing things back then. If you have access to a press, required pullers and replacement parts you could rebuild it. Most likely you'll buy the gasket and a circulating pump and change the pump. I know that's how I would do it.

[DocSki]

Thanks for your reply! My engine is the 5.7 Excalibur. The pump location corresponds to the "circulating pump" in the schematic in the owner's manual. It looks like this:

https://skidim.com/searchanise/resul...rculating+pump.

I've uploaded a picture of where I saw the leak here



and a brief video of the leak in progress after shutting down the engine.

B7F753AD-68C6-43F1-BA96-2F5723B4EA5E.mov

BTW, I keep the boat on a lift and use it exclusively in salt water. I flush it with fresh water religiously after every outing using a FlushPro I installed in the raw water intake hose. Still, salt water is a cancer and may be a culprit here.

I canceled our ski outing this am. I had hoped the leak was a gasket, but hope wasn't good enough when I learned more about the possibility of the bearings being an issue.

Is there is a way to distinguish gasket failure and pump failure short of removing the pump? I'm no mechanic, but with help from this forum I've replaced the thermostat, starter, steering cable, Zero Off antenna, spark plug wires, plugs, cap and rotor, and have done work on both of the fuel pumps. So far so good. But this one looks like the serpentine belt needs to be removed, then re-tensioned, and the pump doesn't appear very accessible. I'm willing to give it a try but I feel out of my league...again.

[SilentSeven]

You can do a quick check the bearing by removing the tension belt and spinning the pump with your hand. You should not feel any grinding or roughness. Should spin with minimum and even effort thoughout the entire 360 circle. There should be no up/down play. There should minimal to no in/out play. This doesn't tell you if it's leaking or not but it will give you some input on how imminent a catastrophic bearing failure might be.

Things can drip leak for quite a while before they fail......

For whatever reason I'm not able to open your links. I don't think the board supports heic type photos. Less clear why the .mov doesn't work. Might just be me....

[DocSki]

Thanks for your advice! Whether it's the gasket or the pump I think I have to do what I've been most anxious about: removing the belt and replacing them both. Sorry the pictures and video don't open. That probably has something to do with Apple's "walled garden." I'm also thinking I should replace the impeller while I'm in the neighborhood (last changed in 2019, but not by me). Any advice, tips, or tricks would be most appreciated. Thanks!

[NautiqueJeff]

Fixed your picture. Here's why it didn't work before:

HEIC Images Not Supported on PlanetNautique

[bturner]

Dang, wish I could see that mov. That is indeed the circulating pump or the water pump as we used to call them on cars. If you're getting water here it's either a cracked/corroded pump housing (since this is a saltwater boat) or a bearing. Either way, it needs to come off and be repaired. I agree with SS on water pumps running a long time even when they leak. That said if mine were leaking it would be out of the water for repair as I don't like taking the chance that a simple relatively inexpensive repair will turn into an expensive one. The "juice just isn't worth the squeeze" for me.

Based on your completed stated repairs this should be a nice technical achievement for you and something you can do by just taking your time. Take a ton of pictures along the way and bag/tag any fasteners as you remove them so you know where they go back. The serpentine belt should be easy to remove once you find the tensioner pulley so you can remove it. One thing I've done when doing this is to break loose the pully bolts on the water pump before removing the belt as the tension on the belt may be enough to hold the pulley while you break free the bolts. If that doesn't work try an impact gun as it won't torque the pulley as much when you're trying to break loose the bolts. Only real wild card I see here is the saltwater which scares the heck out of us freshwater boaters. That said your engine looks real clean.

This isn't your engine but the basics are going to be the same. Actually yours should be easier as you have an inboard and everything should be out in the open.....

https://www.youtube.com/watch?v=46FYu5nUdpQ

I expect to see a write up on your outstanding achievement replacing this pump soon.......

[SilentSeven]

Thanks for your advice! Whether it's the gasket or the pump I think I have to do what I've been most anxious about: removing the belt and replacing them both. Sorry the pictures and video don't open. That probably has something to do with Apple's "walled garden." I'm also thinking I should replace the impeller while I'm in the neighborhood (last changed in 2019, but not by me). Any advice, tips, or tricks would be most appreciated. Thanks!

Sorry...not able to offer any tips on serpentine belt swap outs on that motor. I wouldn't expect it to be difficult....youtube likely has a vid or two on how to do it. Sometimes a special tool is needed....

https://www.harborfreight.com/serpen...kit-63689.html

[shag]

All the above advice is great and accurate. I would also change the impeller annually as well... If it hasn't been changed since 2019, that's quite awhile.. Best of luck and just take your time...

[charlesml3]

Sorry...not able to offer any tips on serpentine belt swap outs on that motor. I wouldn't expect it to be difficult....youtube likely has a vid or two on how to do it. Sometimes a special tool is needed....

https://www.harborfreight.com/serpen...kit-63689.html

No special tool is needed. You'll need to find the belt tensioner pulley. It'll have a big bolt end sticking way out in front of the pulley. The arm on this pulley is spring-loaded. Put a wrench on the bolt end and swing it as though you're loosening the bolt. The bolt won't actually move though. Instead, the entire arm will move back against the spring and give you enough slack in the belt to slide it off.

[DocSki]

Thanks everyone for guiding me through this.
Short story: The project was successfully completed yesterday.
To recap in painstaking detail (also posted on CorrectCraftFan):

I ordered the new circulating pump and impeller on Feb 4 from Nautique Parts. The box arrived on Feb 28 looking like the USPS had dragged it all the way from North Carolina to California and maybe drop-kicked it through a couple of states. Nautique Parts responded and were willing to replace it, but it seemed ok once I opened what was left of the box. So, I finally got a block of time 2 days ago and started in.
1. I loosened the red circulation pump pulley bolts first in order to take advantage of the tension of the serpentine belt (didn't want it spinning while applying torque).
2. Pulling the serpentine belt was a piece of cake. Attach a 15 mm socket to the nut on the tension pulley and turn clockwise. The whole pulley (wheel) moves to port and down to relieve tension. Slip the belt off.
3. Finish removing the red circulation pump pulley (4 bolts).
4. Remove upper and lower hoses on the starboard side of the pump. Simple hose clamps. Water starts to drain into the bilge. (I had tried to keep the bilge dry in case anything dropped. I keep my bilge plug in because I'm on a floating lift--tides, you know--and if the lift sinks with the plug out, game over). I also have an open cooling system (suck up raw water).
5. Using a socket wrench extender remove the 4 bolts attaching the circulation pump to the block. More water drains.
6. Remove the pump. I discovered rust and evidence of a leak on the back plate of the circulation pump. Diagnosis is confirmed.
7. Compare the old pump to the new pump.
8. Freak out. They look very different. The new pump has a brass-looking plug where my old pump has a barbed hose adapter. The housings are very different. Stop. Take pictures. Email Phil at Nautique Parts (he's the one who said he'd send a new pump if mine was damaged).
9. Turn to raw water pump for impeller replacement.
10. Remove pulley (should have paid more attention to advice I was given at CorrectCraftFan to follow instructions from an old PN post. Removing the pulley isn't necessary. Using a socket extender through the gaps in the pulley you can remove the cover without removing the pulley).
11. Remove pump cover. Impeller stayed in the housing and didn't come out in the cover with the twist that was recommended. No biggie. Pulled impeller out with needle-nose pliers.
12. Replaced O rings on pump housing and bolts. **Bolts also have external lock washers.
13. Lubed all with Jabsco Impeller oil and lathered impeller in dishwashing liquid as recommended in old PN post.
14. With impeller in housing, twisted impeller into pump in the direction of water flow.
15. Replace housing with "TOP" up. Got a little over-confident and skipped over that at first. Oops.
16. Start snugging bolts and preparing to torque as directed.
17. Freak out. **A lock washer had gone missing in the now-wet bilge. Even I know enough not to torque 3 bolts when only 2 have the lock washers. Dig around in murky water searching for lock washer, carefully drain bilge, say bad words when I can't find the washer.
18. Run to hardware store for 3 new stainless steel lock washers since they didn't have the same size as the 2 remaining lock washers.
19. Torque bolts to ~9 ft. lbs., replace pulley, spin, and it seems good.
20. Since I started later than I wanted and it was getting dark, pack up to return next day.
21. Email from Phil at Nautique Parts confirms the new circulation pump is the same as mine. Turns out mine has a barbed hose adapter in the upper port for the heater hose. He advises (a) to remove it and use it on the new pump or (b) get a new one at any auto parts store. I chose "a". Back to hardware store for 7/8" box wrench (crescent won't fit in the clearances) to remove the hose adapter and 7/8" Allen wrench (for brass plug removal).
22. Remove hose adapter from old pump and screw it into the new pump (after removing the brass plug--duh).
23. Apply gasket sealer #2 and gaskets to pump (not Permatex; it wasn't available. Learned that #2 sealer doesn't dry solid. News to me.)
24. Using very fine sand paper, gently smoothed up gasket surfaces on the block.
25. Applied gasket sealer to the block and then contorted and twisted and banged my head against the rope pylon (more bad words) while trying to align pump with the block.
25. Tightened the 4 bolts holding the pump to the block in a crossing pattern. Did not torque. There was conflicting advice about this.
26. Replace red circulation pump pulley. Still not sure which size Allen wrench was correct. None fit well.
27. Wound serpentine belt in pattern displayed on engine, then repeated #2 above and slid the belt onto all pulleys and checked alignment.
28. Looked for extra parts and found none.
29. Hooked up fresh water and started the engine.
30. I kept a pretty low profile fully aware of the vague instructions to "close the engine cover" (which is really hard with a freshwater hose attached to the water intake). I'm pretty sure that if something isn't connected correctly a pulley or 2 might start wobbling and go flying out.
31. Nothing flew out and nothing leaked. The water temp came up to my normal operating temp.
32. Miller time.

Thanks again for all the help! Hoping to ski next week. Will check it at higher rpm's before getting too excited.

[srock]

Victory!