Reseal Lower Unit & Replace Water Pump

cheremmi said:

I need to have the lower unit on my 2005 250HP Yamaha resealed ad the water pumped replaced. How big of a job is this and what should i expect to pay tho have the local G/W dealer do the work? Any help would be great.

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Hard to say since rates vary by region. I am not sure what you mean by reseal though. There are prop shaft seals, shift shaft seals, and drive shaft seals. The later are easier to get to. The prop shaft seals are a bit tougher and more labor intensive. For the water pump rebuild, that can be easy or painful depending on whether the woodruff key comes out easily and if the drive shaft cap seal slides off without having to be cut or torched'.

To determine if you need resealing, a pressure/vacuum test needs to be done with the lower oil drained. Of course, you can just tell them to change all seals. Just make sure that it is clear what seals will be replaced.
In one area where I have a boat, the Grady service shop charges $145 an hour. I would think that if everything goes as planned with no snags, removing the LU, replacing seals and the water pump as well as reinstalling should take 2 to 3 hours. To that you have to add parts and fluids. Note that the pump rebuild can be just the impeller and a few gaskets or the entire housing, wear plate etc. The later parts kit is more expensive. Sometimes the drive/shift shafts won't slide off and that can add to the labor times

Sorry I can't be more specific.

Resealed? do you have water in the gear oil?
When was the last time the lower unit was removed?

Replacing the impeller kit can be done by your average mechanically inclined person. dropping out the lower unit requires 2 people because you don't want to be there with the shaft stuck halfway out, yelling for help....
I would suggest that any boat owner who can turn a wrench should learn to do this and they should do it every season....Along with lower unit gear oil and engine oil & filter on four strokes.

Replacing shaft seals is generally not something you are going to be able to do if you are someone who is asking about it.

We just had an f225 lower unit re-sealed and pressure tested, and ended up all-in somewhere between $500 and $650, I think. But that's without a water-pump service, and I had already removed the lower unit from the boat, and removed the thrust bearing from the propeller shaft.

I think your quote is reasonable assuming they're going re:re from/to the boat, pulling the bearing carrier to properly remove and replace the seals, pressure/vacuum test prior to re-filling, and installing a full new water pump kit.

I think it is on the higher end but I usually do this work in conjunction with other work, so probably don't have a good compare. You could talk with a local mechanic that provides services as it is a pretty defined job and get input. The opportunity is probably $100-200 so might not be worth the time.

cheremmi said:

Thank you both for the replies. The quote I was given to do the job was $771.70; $540.00 for labor $180.00 for parts and remainder for taxes and shop supplies. I have worked on smaller older engines and was surprised by the costs. This job does involve (2) O rings, (2) Yamaha oil seals, (1) Yamaha Driveshaft o-ring, (1) oil seal DD type, (2) Yamaha drive shaft seals, (1) Yamaha o-ring lower casing, (1) water pump repair kit($65.80), and (1) castle nut. Based on the two to three hour estimate at $145./hr. $290. to $435; the $540. I was quoted is high, but perhaps not as far out of line as I had originally thought.

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Costly, but not unreasonable. We need to do the port LU due to a little water intrusion. Local mechanic brought his skiff over, dropped the LU while boat on lift, rebuilt completely, i.e. ALL the seals, and pressure tested, then returned and reinstalled it. With new water pump kit as well. A bit less than your quote, but the dealers are always at the upper end.

I would be a little skeptical of the time estimate, as they can easily have "issues" getting everything apart. At least get informed what their policy is about what percent they can exceed a written quote.

I have found that often the longer the time since the last service, the more likely that something won't go as hoped. The frozen drive shaft is one example that can add significant extra labor.
If mechanically inclined, you could do the job assuming you have suitable tools to remove the bearing carrier retainer and a tool to pull the seals. Yo also need some sort of tool to press the new seals into place.
One piece of advice: Note, take pictures, shetch the order AND orientation of every part. Seals install in specific directions as do the spacers and flex washers on the pump. Buy the whole pump rebuild kit, not just the impeller kit. Be prepared to have to go back to the parts store to get parts that are not in the kit but had to be trashed getting them off.

I did one of my 2006 250 last year. The prop shaft seal takes a special puller and can be very tough if corroded at all. The drive shaft seal is pretty easy, but I had to cut away the crescent key holding the impeller to get the seal cover and seal out. Parts cost about $100 from SimYamaha, but it took me all day, including about two hours to cut the key out. I changed the driveshaft seal and did a pressure check to see if the prop shaft seal was good and found it was. I was quoted about $450 by our local dealer to do both if I brought the lower unit to them and if everything came apart easily. It would have required more labor and I think $650 is not unreasonable. Disassembly is the challenge.

wspitler said:

I did one of my 2006 250 last year. The prop shaft seal takes a special puller and can be very tough if corroded at all. The drive shaft seal is pretty easy, but I had to cut away the crescent key holding the impeller to get the seal cover and seal out. Parts cost about $100 from SimYamaha, but it took me all day, including about two hours to cut the key out. I changed the driveshaft seal and did a pressure check to see if the prop shaft seal was good and found it was. I was quoted about $450 by our local dealer to do both if I brought the lower unit to them and if everything came apart easily. It would have required more labor and I think $650 is not unreasonable. Disassembly is the challenge.

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Removing the woodruff key can be challenging but there is a trick I discovered. Use a Dremel tool with a cutoff abrasive disk and grind a slit lengthwise into the outside flat side of the key, Grind as deep as you can without cutting into the shaft on the ends. Now using a vicegrip, squeeze the sides of the key to cause it to 'shrink' width wise. You probably won't be able to see it deform but it does. You may be able to remove the key then with the vicegrip but if you can't get a good hold, tap out the key with a dull chisel or drift. The key should come out easily. Try to ignore the urge to use a torch to heat the key or shaft. If you do need to heat anything, use propane or MAP but not acetyline.

Disassembly is the challenge! Well said!

If you have a great relationship with a great mechanic they may be inclined to offer up what they feel you are capable or incapable of DIY. Then of course you buy the parts from them! Agreed with an above poster, its good to know that basic seasonal stuff and the schedules. If you use the boat as much as some of us you save a lot of time and $$ if you need to do a 100 hour service in July. Basic to me is knowing how to change or swap, (four stroke) engine oil, engine oil filter, the primary fuel filter, block zincs, how to drain the vst, how to drain and replace lower gear oil, spin on water / fuel filters, engine zincs and spark plugs. Anyone with a basic tool set and nominal skills can handle these tasks. Knowing how to do the above you can "winterize" the engine yourself too. Its just one more step.

When it gets to something like a water pump replacement, we have done the work but they can be real time consuming and if you run into disassembly issues a real knucklebuster. Back to having a great relationship, I drop my lowers and BRING THEM, to my mechanic for the pump service. That alone is a savings and I know the job is done right. When you put 150 - 200 hours on the engines (rec fishing), this becomes and annual job. I don't want to even think about a one engine issue 75 miles offshore.

As for bigger jobs, this is where he has told me what I can and cant do, something like a low pressure fuel pump was easy for us to do. 1,000 hour service, not my job to tackle. Tearing down stuff to find the thermastats on my engines, no thanks, (they are buried), I think you get my point? Develop a great relationship with a mechanic and it will pay off long term. Treat them well and with respect and it will go a long way. You guys are dropping off a case or beer and some coffee gift cards to the shop over the holidays, right? Bringing them some tuna loins or tog fillets? Little things go a long way - just saying!

EPPE

As seasick said, that's exactly how I removed the woodruff key. When I changed the water pump in my other engine (didn't need seals) the woodruff key simply tapped out with a drift. You never know! Not a quick process though.