Leak behind pulley on Raw Water Pump

[Hampton]

It took a while to find it, but I have a leak behind the pulley on the raw water pump (pump with impeller inside) on my Stbd 8.1S Horizon. I had my wife run the engine while I sat behind it with a flash light. When she shut down, water began to drip "Behind" (engine mounted backwards, so actually toward the bow) the pulley on the pump.

I assume that this means that the seal is bad on the pump. Is this a full pump replacement item? Do the pulley's come with the new pumps? Good source for parts/pump?

Thanks.

 

[fwebster]

There are replacement kits and even individual parts available. The problem is, is your leak caused by a bad seal, a bad bushing/bearing allowing the shaft to wobble, or a worn shaft so which part do you buy.....buy the whole kit and spend the labor to fix it ? I haven't done one on a 340 with gas engines, but I figure that if you plan to keep the boat a while, run it, depend on it and don't want to enter the leaky pump lottery......I don't think you want to pull that pump off and put it back on but once......... that you are money and certainly time ahead by replacing it.

But, I'm more into long term fixes than saving a few $ on every repair................

 

[northern]

Had same thing happen. In salt water got salt spray that coated inside of engine room. Made 50 mile open ocean crossing before I discoved it. Spent three nights in small port waiting for two new pumps, figured a spare wasa good idea. After taking off the pump the bearings were gone.

 

[sbw1]

My crusaders did the same thing. Crusader replaced the pump with a stainless steel pump housing that has a robust bronze impeller in it. Merc's fix is different, but this apparently was a soft spot on the 8.1s. Mine failed the first year of use and have been fine since I replaced them both.

 

[Jimmy Buoy]

I had the same thing happen last summer. Purchased a new seal, shaft with bearing, and other associated parts. Used a pulley remover, then took the old parts out, replaced with new, and reinstalled the pulley. While the pump was out, I replaced the impeller too.

I may still have photos too if you're interested, but it's pretty basic work. The toughest part was removing the pulley (basically since my pulley puller was crap!)

 

[Hampton]

BOE Marine doesn't carry them. Bought online at Boats dot net. Used a coupon code "internetonly." Total savings $100 plus shipping. Most places wanted 362.75. Got 18% off at that site, then 10% off with coupon, then free shipping.

Thanks to all. Will look into rebuilding old one for a spare, but probably need a housing anyway. Not worth it, if I do.

 

[Hampton]

Had same thing happen. In salt water got salt spray that coated inside of engine room. Made 50 mile open ocean crossing before I discoved it.

Yep. This may be what took out the opposite alternator. I put the original, rebuilt one back on and a week later it looked all used again - getting salt from pump next door. Time to do a really good clean up after putting the new pump on.

 

[Jimmy Buoy]

Follow the link to a diagram and breakdown of the parts and prices (item #4,5,6,7 total about $130.00) needed to rebuild.

http://www.perfprotech.com/store/assembly/SEAWATER-PUMP,7460-210.aspx

Might be helpful to fix up the old one for a spare. I don't think that grooves in the impeller housing would have any impact on the bearings failing. If the assembly's seal (item #4) fails, sea water flows into the bearing area - which would cause the bearing to wear prematurely. When the bearing wears, the spindle pulls to one side with belt tension. That causes the front seal to leak onto the pulley.

 

[Hampton]

Jim - Excellent info - thanks.

After ordering the replacement for $263 delivered, and considering that it takes me about 2 hours to remove/replace these pumps, it's a toss up.

 

[Jimmy Buoy]

Jim - Excellent info - thanks.

After ordering the replacement for $263 delivered, and considering that it takes me about 2 hours to remove/replace these pumps, it's a toss up.

I visited the site, but didn't see how you got those discounts and free shipping. Could you let us know since I'm looking at ordering a few replacement items. Sounds like a great deal!

 

[Kreole Kid]

John, I helped my buddy on his 380 change his (he's a big guy and can't squeeze into every spot in the bilge) port pump and housing. His bearings were shot. If I remember correctly, I think he paid about $230.00 for his replacement and on top of that he got a billet looking pulley with the new pump. He ordered it on line and it was from a Japanese manufacturer.

It's not too hard, just be ready to take up the art of Contorsionism :grin:

 

[Hampton]

I visited the site, but didn't see how you got those discounts and free shipping. Could you let us know since I'm looking at ordering a few replacement items. Sounds like a great deal!

code word: internetonly

293.83 normal price. 10% off with that coupon code - 29.38. Free shipping over $250. Total actually 264.45.

 

[Hampton]

John, I helped my buddy on his 380 change his (he's a big guy and can't squeeze into every spot in the bilge) port pump and housing. His bearings were shot. If I remember correctly, I think he paid about $230.00 for his replacement and on top of that he got a billet looking pulley with the new pump. He ordered it on line and it was from a Japanese manufacturer.

It's not too hard, just be ready to take up the art of Contorsionism :grin:

I've actually done the impellers twice each. The last time, I removed the port side exhaust system to make that job 1000% easier. I got that gouge from a SR mechanic.

 

[Skuza]

One of our pumps started leaking grease so we replaced the whole assembly. Bought it at the dealer and remember it being expensive. If I recall it did come with the pulley installed. May be a totally different model though since you have 8.1's. Good luck!

 

[Hampton]

One of our pumps started leaking grease so we replaced the whole assembly. Bought it at the dealer and remember it being expensive. If I recall it did come with the pulley installed. May be a totally different model though since you have 8.1's. Good luck!

Could've would've should've. Ended up having the pulley bent while having it pulled. Took it to another, highly experienced guy in town who straightened it well enough for a 1/2 week trip. Then, bought another pulley, pulled the pump again, took it to the experienced guy to have that one installed, and put the pump back.

I can now remove and re-install one of these raw water pumps on an 8.1 in well less than an hour. 3 1/2 hours, what was I thinking (3 years ago)?

 

[mawyatt]

John,

Need you to come down to Clearwater and show me how to change the impellers on my 8.1L V drives in 1 hour! Local MarineMax is great dealer and competitive pricewise, at least as boats go, but I may try myself to replace the impellers on the 8.1L and generator (I need to save some $ for gas!). Both are nearing 200hrs. I know you posted a great tutorial on this, but not sure if I can get all contorted enough. I am somewhat old (62) and have a really bad back (I know I know, everyone has a bad back!!).

Guess I'll give it a try and if I get stuck I can always get MM to complete the job and take my gas money!!

 

[Hampton]

Good luck. It's really not that bad, once you've done it a couple of times.

 

[M Prod]

Very useful (old) thread I know, but today as we were just about to pull into an anchorage not too far from home, alarm bells for port engine started going off and the temp started rising. We shut off both engines and popped the hatch ..saw a good bit of water coming in from behind port water pump pulley. Closed seacock and he water stopped. At first I thought I might have a bad hose but that did t appear to be the case on visual inspection. I then pulled on the pulley itself, and way too much play on it. Belt was extremely loose as a result. So it appears the bearings on the pulley have gone kaput. I guess I’ll order the parts Jimmy Buoy suggested here and get to rebuilding seeing as I just replaced the housing 2 months ago. We’ll be limping home at 6knots on Sunday. Thanks guys

 

[Jimmy Buoy]

Very useful (old) thread I know, but today as we were just about to pull into an anchorage not too far from home, alarm bells for port engine started going off and the temp started rising. We shut off both engines and popped the hatch ..saw a good bit of water coming in from behind port water pump pulley. Closed seacock and he water stopped. At first I thought I might have a bad hose but that did t appear to be the case on visual inspection. I then pulled on the pulley itself, and way too much play on it. Belt was extremely loose as a result. So it appears the bearings on the pulley have gone kaput. I guess I’ll order the parts Jimmy Buoy suggested here and get to rebuilding seeing as I just replaced the housing 2 months ago. We’ll be limping home at 6knots on Sunday. Thanks guys

http://www.amarket.com/im496creb.htm

Check out this site. For $190 + shipping you get the bearings/seal/shaft that you need PLUS their wear plate kit for our pumps. I got this kit due to the wear issue with our OEM brass units and the low water pressure resulting from impeller scoring on the housing. Now there's a stainless wear plate on each running end of my pump which still uses the same pump body and end - just their custom impeller that is a bit shorter than stock to account for the wear plate thickness. It's a great mod for these PITA stock pumps. Thought you'd like to know!

 

[M Prod]

http://www.amarket.com/im496creb.htm

Check out this site. For $190 + shipping you get the bearings/seal/shaft that you need PLUS their wear plate kit for our pumps. I got this kit due to the wear issue with our OEM brass units and the low water pressure resulting from impeller scoring on the housing. Now there's a stainless wear plate on each running end of my pump which still uses the same pump body and end - just their custom impeller that is a bit shorter than stock to account for the wear plate thickness. It's a great mod for these PITA stock pumps. Thought you'd like to know!

Thanks Jimmy. Great link and brilliant idea. Why they don't just make these pumps out of SS in the first place is beyond me. I'm guessing they need them to fail so they can make $$ selling new ones. I'm going to replace both pump assemblies in the meantime since I want to get out this weekend and can't wait for parts (Friend has the new pumps already), return the old pumps still under warranty (replaced in March this year), and do the SS plate mod over the winter.

Thanks again!