# Help- can't get the lower drive unit off of my yamaha 9.9 outboard



## peterchech (Sep 2, 2011)

I have my motor off the boat to fix a broken mounting shaft, it's a 1998 yamah 9.9 4-stroke. While I have it out and working on it, I wanted to check the impellor. So I removed the 4 bolts holding the lower drive unit onto the shaft (check the picture. These are the bolts located about 10 inches up from the center of the prop shaft, you can see them in the picture. Well I took off the bolts, and it will not come off. It appears to be corroded solidly in place. I have repeatedly tried penetrating oil and hammering, but this thing will NOT budge and if I take a bigger hammer I'm pretty sure I'll just break something. I can't be the only person to ever have this problem, HOW CAN I GET THIS THING OFF?










If I can't get it off I will just leave it and keep sailing, but eventually I will have to replace that impellor so unless there is some alternative way of getting at it, I have to get this shaft off or I have a useless motor!


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## Capt. Gary Randall (Jun 1, 2012)

your missing something? Bolt? look closer


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## chucklesR (Sep 17, 2007)

Taking the lower unit of my outboard involved cutting the paint seal (box cutter), and even then I needed wooden wedges and a hammer. 
Make sure you have all the bolts/nuts off - then tap around and round.


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## dabnis (Jul 29, 2007)

There is a shift shaft that goes from the power head inside the lower unit to the gear case. There may be an acess cover to disconnect it somewhere on the lower unit.

Used Cars, Pets, Jobs, & Real Estate | Classifieds on recycler.com

Part # 35

Paul T


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## chucklesR (Sep 17, 2007)

dabnis said:


> There is a shift shaft that goes from the power head inside the lower unit to the gear case. There may be an acess cover to disconnect it somewhere on the lower unit.
> 
> Used Cars, Pets, Jobs, & Real Estate | Classifieds on recycler.com
> 
> ...


Oh yeah, that too. All the bolts and nuts.


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## dabnis (Jul 29, 2007)

Done a number of impeller replacements. The hardest part for me was getting the water tube back into the powerhead. There was an O ring that kept falling out of the block. Finally put some sealer around the outside, let it dry a little then put it in the block. IIRC, on a smaller motor I just tipped it upside down in a corner. Much easier and could actually see what I was doing.

Paul T


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## KBuckley (Sep 17, 2008)

There is a service manual available online (https://docs.google.com/file/d/0B6B...Zjc5LTkzN2YtZWJmOWRkNzk2ODJk/edit?hl=en&pli=1) that shows the shift rod that needs to be disconnected but I do not see the access to the connection (at least in the few minutes I looked at the manual). Probably it will be obvious to you with the engine in front of you and the pictures in the manual.

Good luck.


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## MarkSF (Feb 21, 2011)

On my Yamaha 8, the shift rod is accessed from the outside of the o/b. If you place the outboard flat on a bench, with the prop downwards (so the throttle arm would be pointing straight up), you will be able to see the shift rod easily.

Note that there is also a small black plastic lever near to the shift attachment point, that is easy to break, this operates the reverse gear / tilt interlock.

On this diagram of the 9.9, it seems to be items 33 and 34 that attach the two halves of the shift rod :

1998 9.9MSHW Yamaha Outboard CONTROL Diagram and Parts

Put it down on the bench and see if you can see them.


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## peterchech (Sep 2, 2011)

Yeah the shift rod is bent had to be replaced. It is inside the shaft itself on the 9.9. 

There doesn't appear to be anything holding the bottom drive unit onto the rest of the motor except for a ton of corrosion at the point of the seal. I thought about hammering a chisel into it all around slowly, but I'm concerned it will come off and be pitted and scratched, so sealing it in the future might be impossible.

Chuckles u were able to use wooden wedges? I don't have more than 1/32 " of space to get anything in that gap on my motor...


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## gershel (Feb 4, 2001)

This is the best advice.
Marc

PDQ Forum • View topic - T9.9 lower end removal questions


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## Capt. Gary Randall (Jun 1, 2012)

Remove anode at front of lower unit, there should be a bolt that connects the lower gear housing to the upper housing. That is the way a lot of them are in my previous experience. CaptG


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## gershel (Feb 4, 2001)

Capt. Gary Randall said:


> Remove anode at front of lower unit, there should be a bolt that connects the lower gear housing to the upper housing. That is the way a lot of them are in my previous experience. CaptG


Not on the Yamaha 9.9 4-stroke.


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