Replacing Impeller 99 90 hp Force

shurt

Seaman Apprentice
Joined
Aug 27, 2007
Messages
41
1999 90 H.P.
Serial # 0e 355074
Model # H090412VT


Trying to figure out how to disengage "shifter rod" to drop lower unit to replace impeller. I cant find anything on this. I've seen them with the nuts (Mid section)that come apart as well as the pin that can be removed up top. Cant find either on mine. Is it possible that I can just drop it without disconnecting "shift rod/unsure of part name"? Thanks in advance for any help.
 

roscoe

Supreme Mariner
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Oct 30, 2002
Messages
21,657
Re: Replacing Impeller 99 90 hp Force

Is it possible that I can just drop it without disconnecting "shift rod/unsure of part name"? Thanks in advance for any help.

Yes. The later model years used the Mercury rotating shift rod. It is a splined connection, just like the driveshaft.
 

shurt

Seaman Apprentice
Joined
Aug 27, 2007
Messages
41
Re: Replacing Impeller 99 90 hp Force

Thank you Sir for the prompt reply. I see some sort of sealant around the exhaust "port" ...Any preference on sealant? Last Question for this task, It also appears that four bolts holding on Impeller housing had some type of thread lock or Loctite on them. Is this also something I should do? Thank you again
 
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jerryjerry05

Supreme Mariner
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May 7, 2008
Messages
17,923
Re: Replacing Impeller 99 90 hp Force

Yup just drop it,make sure it's in forward gear.You shouldn't need any more sealant unless you remove what's there.
Yes anything on the screws.I use marine grease. Locktite,no.
When reinstalling the drive,if you have turned the prop at all it will slip out of gear.
From the rear,right hand,pull up on the right prop blade,it should make the driveshaft turn.
If not then turn the shift rod to the left,all the time pulling up on the blade untill it connects.
 

shurt

Seaman Apprentice
Joined
Aug 27, 2007
Messages
41
Re: Replacing Impeller 99 90 hp Force

O.K guys thank you for your time. Here is where we are now, Ive been trying to post a pic for last hour :grumpy:...
Noticed I have Oil leaking out lower unit from a small hole on right side of lower unit. I'm assuming I have a blown seal somewhere in the lower unit. I will continue to try and add a pic of area of leakage ASAP.

http://www5.snapfish.com/snapfish/s...otsc=SHR/otsi=SPIClink/COBRAND_NAME=snapfish/
 
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shurt

Seaman Apprentice
Joined
Aug 27, 2007
Messages
41
Re: Replacing Impeller 99 90 hp Force

UPDATE: Below is a picture or where the oil was pooled and leaked thru "weeping hole??" in lower unit.

http://www5.snapfish.com/snapfish/s...otsc=SHR/otsi=SPIClink/COBRAND_NAME=snapfish/

This is picture of where that chamber would connect to mid section when lower is attached.

http://www5.snapfish.com/snapfish/s...otsc=SHR/otsi=SPIClink/COBRAND_NAME=snapfish/

That said, I am assuming my leak is a seal from upper part as opposed to lower...The Oil leaked down thru the Port directly behind the Exhaust Port. I will also add that Engine was stored raised in garage and was lowered prior to removing lower unit. I'm pretty sure thats when the oil escaped from that weep hole. Is this normal? If Gasket below faceplate was bad, would that allow oil leakage/ I did replace same with impeller.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
Re: Replacing Impeller 99 90 hp Force

That's probably just unburned gas/oil.
Just to make sure,drain it and pressure test it.
 

shurt

Seaman Apprentice
Joined
Aug 27, 2007
Messages
41
Re: Replacing Impeller 99 90 hp Force

Thank you for the reply. For clarification purposes, I drain lower unit fluids and then pressure test (No more then 8-10 PSI??) I'm worried about blowing seals. If I have a leak i should hear it or I can spray some soapy water onto seals etc. I did not smell any gas in leaked fluid, nor was there any burned smell of oil that had leaked out. Actually had very little smell.
 

brnschoneck

Petty Officer 1st Class
Joined
Feb 22, 2013
Messages
337
Re: Replacing Impeller 99 90 hp Force

y exactly no more than 10 psi ...and ull here air coming out if u have a bad seal ..u shouldnt need to use soapy water but u can ..
 
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