Volvo penta 2003 raw water pump – easy fix?

[redbeard1]

Hello all,

Yesterday, during our weekly engine maintenance, we noticed water dripping (a drop each five seconds) from the weep hole on our water pump">raw water pump.

We are leaving for a ten day cruise around Lake Michigan in 7 days. Our time before we leave is limited and we cannot find a replacement pump that would arrive in time (not to mention they are pricey).

We read in another posting that on some Volvo Penta raw water pumps, the water seal can be pushed out by hand via the opening for the impeller by pushing through the weep hole.

1) To anyone with a Volvo penta 2003 OEM water pump – Have you ever pulled the water seal on your pump without removing the water pump? Is it doable in the 12 hours we can dedicate to this before our trip? I have replaced timing belts on cars so I feel comfortable around tools and engines.

Looking at the design of our pump, it seems to me that water cannot make its way into the bearings. The weep hole seems to divide the water side from the oil/bearings/engine side.

1) To all – Would you all agree that my bearings are isolated from the water?

2) To all – How long before the leak becomes a stream? It has not escaped our attention that this seal is all that separates our bilge from the raw water intake.

Thanks to all

[Diesel Bill]

Do you feel lucky? Well do you? No really, A pump seal can leak like that for years or it could let go and become a torrent in the next 5 minutes. Depending on access you could have the pump off and on the work bench in under 30 mins. Changing out the seal should be straight forward.

[Mundinho]

To pull pump, pull impeller and renew both shaft seals + renew o-ring on shaft will take approx. 1 hour work. You need to have the shaft seals (2x) on board. Best is to have overhaul kit o/b, which contains also shaft.

Dripping is no problem, even severely dripping you should be able to keep bilge empty. The problem with severe leakage however is that this can cause seawater to bypass both shaft seals and enter engine side, causing water contamination of your engine oil. We just had this happen to us this year.

[redbeard1]

Diesel Bill, thanks for replying. While i don't feel too lucky, a man's gotto know his limitations. Right now, mine are no access to a work bench, vice etc. I have read some pumps require use of bench and other tools to pop out inside pieces of pump. I'm hoping i can swap out water seal with pick or push it out via weep hole. Otherwise, I may need to wait until I get back.

Muldinho, thanks. That time estimate, is it for a volvo penta raw water pump? I saw a video for a another brand water pump and it looked like it might take a while to fabricate the doodads needed to pop out the innards.

[Mundinho]

Yes, that is same VP pump, I recognize the drawing. It is straight forward. Remove two nuts. Remove pump. Pumps comes off easily. Open cover. Remove impeller by inserting into impeller two screw drivers, be careful not to damage seal face for cover. Tap with hammer to remove shaft. Remove bearings ( stay in housing) with pipe end (if you intend to replace bearings, if bearings ok, no need to replace. Place new bearings in freezer for 1 hour before tapping them in place. Place shaft in freezer before tapping in place. Replace seals prior shaft. Don't forget o ring between both seals. The o ring functions to prevent water from entering engine if water seals fails. It is straight forward and is self explaining once you get started. But you need to have the seals on board and preferable bearings + shafts as well. I waited too long with s dripping seal, which turned into a pouring seal while still 5 days offshore. Me thinking no problem, water cannot get into engine. Wrong, water did end up passing the oil seal causing water contamination in LO.

[redbeard1]

Mundinho - Thanks for that great explanation. Mostly clear to me but I have two follow-up questions.

After I pull off the pump, which end of the shaft do I tap with the hammer? The impeller end or the engine-side end of the shaft?

Also, how hard am I supposed to hit the shaft? I don't want to damage the shaft so I imagine I should put a wood block between the shaft and the hammer.

Thanks.

[Lepke]

The bearings and seals should be available at a good bearing supply. Take the seals and bearings. Another option might be to have a marine or pump dealer rebuild it if it fits your time frame. Dripping seal can go fast or last days. Usually a dripping seal is because of the bearings wearing out. So a new seal with old bearings...
Raw water pumps are not hard to rebuild, I've been doing it since I was 13.
Depco pump should have all the parts and could ship air for your deadline.

[jamesdavis]

If raw water is leaking past the seal (#9, 15), your bearings are susceptible and will eventually corrode -- if they haven't already.

Sea water leaking into the inner bearings will sooner or later cause those bearings to fail, falling apart and seizing up on the shaft.

[jamhass]

All above info is just fine.

In the event you cannot source seals with SS springs (the spring ensures the lip has enough preload to effect a good seal, and most seals use a spring steel) you can remove the steel spring and replace it with an appropriately sized o-ring.

A couple of additional notes:

Use a soft hammer (lead, brass, plastic) or put a soft drift between the hammer and shaft.

On reassembly, an appropriately sized socket makes a very nice drift to (carefully) drive the bearing and seal onto the shaft or into the body of the pump, possibly needing a deep socket. In many cases, a bit of PVC pipe can work well also.

[Paul L]

Originally Posted by jamhass

All above info is just fine.

In the event you cannot source seals with SS springs (the spring ensures the lip has enough preload to effect a good seal, and most seals use a spring steel) you can remove the steel spring and replace it with an appropriately sized o-ring.

......

If you get the replacement seals that were meant for an oil environment with the standard steel spring, you can pop the stainless spring off the old seal and put it on to the new seal.

[redbeard1]

Thanks to all for the replies. I learn so much from this site every time something breaks on the boat.

I think we will try to just replace the water seal for now as suggested by belizesailor in the link below.

http://www.cruisersforum.com/forums/...nt-140210.html

It is a ten minute job and the 3 hour drive to/from the boat to somewhere with a bench/vice is too daunting. We do careful maintenance each week so I'm pretty sure the pump only began to leak in the last week.

After the cruise, we will pull the pump using the tips above and rebuild properly. Again, thanks to all.

For anyone else with this issue, I found the link below helpful in understanding how the pump works.

Rebuilding A Raw Water Pump Photo Gallery by Compass Marine How To at pbase.com

[redbeard1]

Thanks to all again. The repair went well. Two days of engine use and no leaks.

We were not able to push through the weep hole and used a pick to remove/destroy the old water seal.

Tip for anyone else who tries this repair. The screw that holds the cam plate in place had a crush washer (4mm ID 8MM OD). This crush washer was not in the volvo parts diagram. Make sure you have a spare on hand in case the old one does not seal.