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Jason, Marine Mechanic
Category: Boat
Satisfied Customers: 18750
Experience:  Degree in Marine Technology. Gas and diesel marine mechanic.
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I can't remove the driveshaft. I need to replace the shaft

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I can't remove the driveshaft. I need to replace the shaft bearings. 2005 mercury 25 hp 2 stroke
JA: Sometimes things that you think will be really complicated end up being easy to fix. The Marine Mechanic I'm going to connect you with knows all the tricks and shortcuts. Tell me a bit more about what's going on so the Marine Mechanic can help you best.
Customer: The shaft will slide up and down put will not come out of the housing. I have removed the bolt and egar on the bottom
JA: Is there anything else the Marine Mechanic should be aware of?
Customer: I found roller bearings inside the housing. But everything looked good on the propeller shaft. so, a roller bearing came apart on the drive shaft

Good morning, my name is ***** ***** am I speaking with/ I read what you wrote. Mercury outboard are cataloged by serial number, and not by year. Can I get the serial number on your outboard so I can ID it.

Customer: replied 5 months ago.
I am at work but I know the first numbers are OT98 series.

Okay got it. I know what you have. Do you have the propeller shaft portion of it out? If yes, do you have the pinion gear off? How far along are you in the process? Are you working with the service manual for the engine?

Customer: replied 5 months ago.
I removed the nut and took the pinion gear off at the bottom of the shaft. The drive shaft will slide up about 8" and comes to a sudden stop. I did see roller bearings fall out of the shoot the drive shaft is in. They fell into the lower casing. So, I assume the roller bearing in there for the drive shaft came apart. I am not sure if what is left is stuck on the shaft and is preventing me from sliding it out? Or should it have came off? I do not see the casing or race for the roller bearing.

Hi Scott. It should pull right out. Is the shaft bent at all, does not look bent if you try and spin it? Can you push it back down into place?

Customer: replied 5 months ago.
Not bent. Everything looks good. The shaft will push back down. I even tried putting a pair of vice-grips on it and tapping with a hammer. The lower unit did get hot the last time out on the water due to no oil. I am wondering if maybe part of the bearing that came apart that needs replaced got welded to the shaft from the heat? Is that what I am getting stuck on?

Yeah that is very possible. I've seen that on propshafts where they weld themselves to the gear. Do you have a heavy duty 5 or 10 slide hammer?

Customer: replied 5 months ago.
I do not but was considering getting one. How would I attach it to the shaft?

So what you would need to do is lock the lower unit down tight in a holding fixture. Then, take something like a heavy duty propeller thrust washer, or a couple of heavy duty washers, and slide them on the drive shaft. Next, just below the splines on the top of the driveshaft, clamp on 1 or 2 pairs of vice grips, as tight as you can make them, to the top of the shaft. After that, slide the washers up the shaft, holding tight against those vice grips. Tighten up the jaws on the slide hammer to that washer. Then pound away, and it will come out. It is okay if you chew up the shaft a little bit with the vice grips as long as you do not chew up the splines itself. Does that all make sense to you. I think that should do it but I work for tips so I do want to make sure you are happy with my service before you go. If you had a further question on the issue by all means feel free to ask. If not, Just in case you do not understand the way the website works (and some folks do not). You do have to put forth a positive rating in order for it to credit me for helping you. When ratings are not done, the website simply keeps your deposit and they will not credit me. The ratings box is located at the top of the screen. To rate, you must select the star you wish and also confirm it. Please let me know if you run into any problems or errors when trying to do it. If you do have a problem, or if you can not see the ratings box which is at the top of the screen. Please reply back "I rate Jason's service _______" and fill in the blank.

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Thanks in advance, and good luck

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