Suzuki DT75 '85 lower unit removal

stevek123

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I am trying to remove the lower unit so I can replace the water pump. I have removed all of the bolts, four on each size plue the one in the back center. I removed the shift linkage from the top. I have read all of the other posts about how simple this procedure is.

It is a saltwater boat (Hawaii). The lower unit does not budge. It's as if I haven't removed the bolts. I have repeatedly verified that all of the lower bolts are off. I have gone through the forums which confirm the number of bolts I have removed and sometime mention the shift linkage needing to be disconnected. I have a Suzukie service manual which sucks when it comes to removing the lower unit. I have a Clymer manual on order.

Any help would be appreciated. Thaks.
 

JUSTINTIME

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Re: Suzuki DT75 '85 lower unit removal

put a block of wood on the lower unit and hit the wood
 

James R

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Re: Suzuki DT75 '85 lower unit removal

Put the brakes on.
Have to remove the couple to the clutch shaft.
Go to www.brownspoint .com,click on parts,click on DT75.Select 1985 model and go to Clutch drawing.
Back off nut #5,do not remove. Push shaft #7 to dissengage from the clutch shaft #8.
Go to Gear Case drawing. Bolt #15 needs to be removed also.
Once this has all been done that lower should pull right off.
You can easily break the aluminum casing or fins etc. Dont hammer on the fins. Try using a rubber mallet alternately on each side of the lower case.

Remember as with all outboards, if it doesn't come apart easily chances are that you forgot a bolt.
 

stevek123

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Re: Suzuki DT75 '85 lower unit removal

James R. Thanks for the very detailed and easy to follow instructions. Unfortunately, I have already done both of those steps.

Not to distract from the main problem but I have taken nut #5 all of the way off. Is this going to be a problem later?

Anyway, it won't matter if I can't get the lower assembly off. I sprayed Liquid Wrench on it overnight and have gotten frustrated and pounded it with a rubber mallet. It doesn't move. Next option is a sledgehammer and the junk yard.

What else could I be missing or what is the best way to release the lower unit if it is frozen from corrosion? Thanks.
 

stevek123

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Re: Suzuki DT75 '85 lower unit removal

I got the #5 nut back on loose. Will this be a problem down the road?

I hit the spot where it looks lile the lower unit starts with hammer using a piece of wood. No luck.

What will unfreeze corrosion if that is what's holding it together? What are alternative diagnoses? Thanks.
 

James R

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Re: Suzuki DT75 '85 lower unit removal

Have you removed the seven bolts and two nuts securing the lower?
One of the problems encountered, when used in salt water, is the studs and the casings corode and weld together. People and the manufacturers fail to coat the studs and bolts with a sealer.
If all bolts and nuts are removed and hopefully the drive shaft has not coroded in the powerhead splines, the casing of the lower unit at the studs will have to be heated to break the corosion around the studs. This requires great care and a lot of heat. Remember too much heat in one spot will destroy the aluminum. You may be well advised to take it to a marine shop that is familiar with this procedure.
 

stevek123

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Nov 5, 2008
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Re: Suzuki DT75 '85 lower unit removal

All the bolts and nuts are definitely off. I don?t think the drive shaft is corroded because the motor runs and the propeller is spinning. The lower unit is locked onto the rest of the motor.
 

James R

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2,660
Re: Suzuki DT75 '85 lower unit removal

The motor can be running normally and the drive will work fine but the drive shaft can be locked up in the crankshaft due to corosion. This can prevent the lower removal. Go to heating the casing at the studs to break the corosion around the studs.
 
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