2013 Mercury 125 Optimax, stuck 5" Expansion on Lower Unit

[jonnorris1000]

I am in the process of replacing my impeller in my Merc 125 Optimax long shaft. I took the lower unit off and all was well until I noticed that I have a 5" extension housing section on the lower unit to make it a long shaft and have to take that off before being able to take the water pump housing off to replace the impeller. And it would appear to be stuck on there from the factory since this is the first time the impeller has been changed.

​Problem is I can't get the extension section off the lower unit, from what I can see there are no more bolts holding it on it seems stuck. Any ideas on how to get this apart, my guess there is gasket material still holding it on usually bad things happen when I try forcing it, but perhaps I am missing something. Appreciate the help in advance.

 

[Dukedog]

tha 5" drive shaft extension?

 

[jonnorris1000]

The 5' Extension that makes the lower unit longer (housing extension section) I attached a picture with my original post. Appreciate the help, it will save me a trip to the repair shop. Figure there is a trick to it other than brute force which usually ends badly.

 

[Dukedog]

picture is to big... is it tha piece on top of tha drive shaft or tha piece between tha down housing and tha gear case?

 

[jonnorris1000]

Its the housing on top of the gear case, 5" section of housing between the gear case and down housing. Its the actual housing not the shaft extension. In order to get the water pump housing off the lower unit 5 " housing extension should come off but it is stuck on there.

 

[Dukedog]

gottcha... pb blaster (or something similar) with a tad bit of heat and a lotta patience!!!

 

[GA_Boater]

Welcome aboard.

Back up a little and take a couple of more pics. Some from the lower unit side would be nice.

BTW - This is the extension or similar, stuck to the LU.

 

[jonnorris1000]

Here is another picture, correct that is a similar section shown above. The housing is stuck on there. You can see the line where the extension meets the lower unit. I may try to apply some heat where the manifold / exaust travels perhaps this will help loosen the gasket sealer they use. I am assuming there is nothing else holding it together. The only remaining bolts I see are for the water pump and gear shaft seal on the lower unit itself.

 

[GA_Boater]

Looking at Boatinfo, the lower unit installation instructions say to use some silicone sealer on the top of the divider block, whatever that is. But the silicone may be what's holding the lower onto extension along with the two fore/aft guide pins. Gentle tapping should loosen the two sections as long as you are sure all bolts and nuts are removed.

 

[jonnorris1000]

Unfortunately I have done all the gentle tapping with a rubber mallet that I can do, may have to try heat. Next step will be to load it up and take to a mechanic. Was hoping to be able to do basic maint myself but perhaps not the first time in this case. I think it is silicon hopefully light heat will loosen it up. Otherwise will make it someone elses issue. Let me know if you can think of anything else I can try.

 

[jonnorris1000]

No luck with the heat method, its on there solid. Will PB Blaster dissolve silicon?

 

[jonnorris1000]

Took it to a mechanic and he was able to pry it off, bigger hammer is the answer for once.