T9.9 lower end removal questions

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Magic Time
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T9.9 lower end removal questions

Post by Magic Time »

I have a T9.9 exrw on a 32' .I would like to remove the lower end unit. I have disconected the shift linkage, I have removed the four nuts holding the unit to the upper casting. The unit will still not come away from the upper casing. I have soaked the studs with pb blaster and have heated the casting with a propain torch to try and loosen the bond. I can see movment between the two castings but not enought to insert a wedge or screwdriver.

I am looking for suggestions.

Any thoughts are appreciated.
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Re: T9.9 lower end removal questions

Post by Allezcat »

Magic Time,
I have posted on this a long time ago. Do not pound on the cavitation plate. It will break. It is likely the driveshaft splines are stuck in the powerhead. My only success in this was to construct a crude but effective puller. It consists of two 4 X4 wood pieces hollowed out to match the contour of the lower unit. this clamps to the lower unit using threaded rods. I then used two long rods from these pieces (about 3ft each) to another piece of 4X4. With all this in place and the engine on the floor, a couple good whacks with a sledge on the single 4X4 easily removed it. I have used the device on several engines. You have to be sure the shift rod is disconnected. I lent the device to a a neighbor that successfully removed the stuck unit but also pulled the shift linkage right out with it. I have a couple spare lower units if you ruin it. I would give up on the heat. I had a Yamaha dealer ruin a unit using that approach. I could take a photo if needed.
Good Luck
Chet
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Re: T9.9 lower end removal questions

Post by duetto »

based on what you've done, i agree with chet, it has to be the splines stuck in the bottom of the crankshaft.
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Re: T9.9 lower end removal questions

Post by thinwater »

I have used a simplified version of Chet's method 5 times on 9.9s in the past few years; worked every time with very little fuss.

Simply clamping the 4x4s and tapping on those (VERY hard tapping) around the edges did the trick. I even did it in the water once, though I don't recomend that if you havn't done it before.

http://sail-delmarva.blogspot.com/2011/ ... pumps.html

When you put it back together, lather it up with telflon paste. And be VERY careful with the shift; I twisted one off and it is a bas__rd to replace.
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"Rigging Modern Anchors,"Seaworthy Press, https://www.amazon.com/Rigging-Modern-A ... 1948494078
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Magic Time
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Re: T9.9 lower end removal questions

Post by Magic Time »

Thank You all for your responces. I have been unable to continue this repair project untill recently.
I have Questions
Allezcat, Would you please reply on to this post where or how to find your article. Did it have photos. I am not vary framiliar with how to us or navigate forums in general, so would a link placed on this post direct to your article. (I tryed searching using removing lower unit and removing lower end also lower end removal. Could not find your post on this subject.
If your original article did not have photos of this wonder tool ( the block ) I would apreciate it if you would post some.

A few fact about this motor.
It was emersed in salt water and therefore the power head is seized. I am sure you are right that the drive shaft splines are corroded into the crank shaft.
The Question is how badly.

Do you think the following procedure would work, perhaps with a little more contole.
Attach a lifting ring to the flywheel via a plate and 3 bolts into the flywheel puller holes. Tie this with a rope to an unmovable object ( fence post) then tie two short ropes around the lower unit in a way that there will be eaven pulling on each side of the lower unit .
Attach these ropes to a small come along which is conected to an other unmovable object ( another post ) Them apply pull using the comealong to pull the drive shaft from the power head. This should produce a very controled pulling power in alignment with the two shafts (crank and Drive).
My biggest consern with this posible technique is, that I am going to damage something in the lower end such as, breaking the bolt off that retains the pinion gear onto the end of the drive shaft and then pull the water pump apart in doing this.

What are your comments.

My alternative would be to dissasemble the power head to the point that I can access where the lower unit drive shaft splines go into the crank shaft then apply some heat, with a tourch to that coupling area. ( That is if I can reach that area) And then pull the two apart. I have removed many rusty nuts will a tourch.

for future refrence could you tell me the name of the manufactureer of Teflone paste that you use. I am unaware of teflon paste and I would contact them to find a supplyer near me.
Thanks again for the assistanc so far.
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Re: T9.9 lower end removal questions

Post by Allezcat »

Magic Time,

If this motor has been submerged in seawater it may not be salvageable. I think the problem with your approach is that a steady pull using ropes, etc. will normally not be sufficient to break loose the seized parts. It takes an impact.
I have attached a couple of photos. The first shows the apparatus with the threaded rods and blocks. The second shows the procedure which involves a sledge. Usually one or two whacks will be all it takes while someone steadies the motor on the floor. Be absolutely SURE that the shift rod is completely disconnected if you try this. I have never tried it on a submerged engine (disclaimer!)

Good luck,
Chet
Attachments
Removal Tool
Removal Tool
P1040646.JPG (134.24 KiB) Viewed 17356 times
Removing Lower Unit with Sledge
Removing Lower Unit with Sledge
P1040640.JPG (128.18 KiB) Viewed 17358 times
Magic Time
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Re: T9.9 lower end removal questions

Post by Magic Time »

Thank you Chet for posting those two photos. Seeing always is the best description.
I will try this on the weekend and let you know how it went. and yes the shift connector is definitly disconected.
MT
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Re: T9.9 lower end removal questions

Post by Magic Time »

Well thanks to the advice of fellow pdqers I now have another lower end as a spare.

The lower end unit did not come off in the first whack. As a matter off face it healed on until the castings were about an inch apart. There was a lot of sand and dirt packed around the water pump housing and this seamed to be what was holding the lower unit to the main casting. I turns out that there was no rust in the splines of the drive shaft.

I can not understand where the sand came from.
Can any one tell me the path that the water takes when it enters the lower end side intakes.
I find it hard to believe that the amount of sand that I found in the inside cavity above the water pump came all the way threw the engine and was deposited in the area around the top and down the sides of the pump housing.

Any insight to this ?

My next task is to replace the oil seals in the other lower end unit.
Attachments
Lower end b.jpg
Lower end b.jpg (167.03 KiB) Viewed 17214 times
Note the sand trail on the plywood
Note the sand trail on the plywood
Lower end a.jpg (191.23 KiB) Viewed 17213 times
Marc Gershel
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Re: T9.9 lower end removal questions

Post by Marc Gershel »

Probably ran into very soft silt, that didn't stop the engine. It just kept running and sucking in silt.
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Re: T9.9 lower end removal questions

Post by duetto »

after you get it running make sure it gets water circulation up thru the head. you should get water pouring out of the holes abobe the cavitation plate. if you got that much sand in the lower housing AND it came thru the water pump, it may have clogged some of the water passages in the head.
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Re: T9.9 lower end removal questions

Post by amytom »

Have you changed the gear oil on this lower unit yet? You may find it full of sand also.
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