3.0 outdrive oil coming out of water intake where earmuffs go

[Racerjoe]

waa out lookkng over one of my pontoon boats this morning so I could take it and put in the lake as I need to use trailer for anothr boat. Noticed the outdrive oil resevoir wa empty so I filled it up. When walking around it later I noticed that the gear oil was coming out of the vents (water intake) where the ear muffs go to run on the water hose. Drive was left about 1/2 way up over the winter as it would not trim down at the end of the year. Coukd something have frozen and busted? What could cause the drive oil to leak out of this area??? 3.0 / Alpha one anout a 1998 model .

 

[Bt Doctur]

Coukd something have frozen and busted?
Unlikely
What could cause the drive oil to leak out of this area???
a leaking upper driveshaft seal or a lower water pump base seal

 

[Racerjoe]

Thank you for the input - I appreciate it man! I will order those parts tomorrow and get it done as I need that trailer to get my other pontoon home so I can stand on the ground and fix it!!!.. I think I jump to the freeze and crack too quickly as I had a 4.3 do that a couple of years ago in a SeaRay. I learned the hard way that there are no holes in the rear of the intake to let the water run out like there are on the Chevrolet 4.3. Everyone said the block is cracked - buy a short block... I did rebuild entire engine but found that the only think that froze and split was the bottom of the intake. Now I open all drains and put the boat down very far in the "bow down" position to let it drain... No problem since.

 

[Bondo]

as I had a 4.3 do that a couple of years ago in a SeaRay. I learned the hard way that there are no holes in the rear of the intake to let the water run out like there are on the Chevrolet 4.3.

Ayuh,.... Welcome Aboard,..... Those are the Exact Same motors,....

I will order those parts tomorrow and get it done as

You'll be wiser to tear it down, See what ya need,....
Then get the parts necessary,.....
Generallites are bein' spoken here, not specifics,....

 

[Racerjoe]

I may have misspoken..... small block chevys do not have the back two water ports blocked off and “everyone” has always told me that a 4.3 is simply a 350 with 2 cylinders chopped off therefore I dimply assumed that the 4.3 rear water jackets on the intake were open as will all SBC.... my point that I was kinda mentioning but did not make very clear was for folks not to jump on the “block is cracked - need a shortblock” bandwagon.

Im going to order tge parts as it has been over 5 years sincd a waterpump has been put in this drive... it is time anyway. And they are dirt cheap compaired to labor.

Thanks for the input.... you guys keep it coming (it is very much appreciated). I will report back what I find. Also if you get a chance I have a post on the Mercury forum asking what a part is..... i seriously need some help figuring that one out... it could be my entire running problem with that Merc 90 if not I did find a CDI troublshooting guide online kast night.

 

[Racerjoe]

Also.... point well taken on generalities... but I have found this to be a common problem after running coutless searches on it this morning.

 

[Bondo]

I may have misspoken..... small block chevys do not have the back two water ports blocked off

Ayuh,.... There are 2 water ports on the heads of both motors, so the heads can run on either side,......

On Chevy V-motors, the intake manifold has Only front ports,....
No water beyond the front 1/3rd of the manifold,.....
The heads, 'n intake drain down into the block,...

So, on All Chevy V-motors, the aft head water ports are blocked off, by the solid surface of the manifold,....

Lot ta learn, Quickly, eh,..??

 

[Scott Danforth]

I may have misspoken..... small block chevys do not have the back two water ports blocked off and “everyone” has always told me that a 4.3 is simply a 350 with 2 cylinders chopped off therefore I dimply assumed that the 4.3 rear water jackets on the intake were open as will all SBC.... my point that I was kinda mentioning but did not make very clear was for folks not to jump on the “block is cracked - need a shortblock” bandwagon.

you really dont know motors do you.

all GM V motors have water passages in the heads so they can be used on both sides like Bondo pointed out. None of them use a rear-cross-over in the intake manifold...... ever

putting your boat in a bow down position is a good way to a rotten hull.

 

[Racerjoe56]

Thank you for guys for the valuable (helpful and non condescending) input from BT Doctur and Bondo - very helpful info and that was my understanding of what forums were all about at least most of the other ones I am on are....

BUT a VERY special thank you goes out to the one ....the only... Scott Danforth! (Oh BTW many people think it is someone just wanting to hear their own jaws flap in the breeze when you just repeat what someone else just said... FYI)

"all GM V motors have water passages in the heads so they can be used on both sides like Bondo pointed out"

Have a nice day!

 

[porscheguy]

Check the shift shaft seal. I’ve got two alpha1 drives and they went bad on both and allowed the oil to leak out. Requires a special tool to change it, but the tool is usually available wherever the seal is sold.

you need to change your anodes.

 

[Racerjoe]

Check the shift shaft seal. I’ve got two alpha1 drives and they went bad on both and allowed the oil to leak out. Requires a special tool to change it, but the tool is usually available wherever the seal is sold.

you need to change your anodes.

Ok so I have this lower section of outdrive off and bought a new shift shaft bushing "housing" (it bolts to the lower section with 2 bolts just in front of the water pump.) The shift shaft runs through it then looks to go into a "shift crank". Can I simply lift the shift shaft out and replace this bushing or seal housing? It looks too easy and I have run a bunch of searches online and have found nothing. I am worried (I do not know exactly how it is made) that the shift shaft may not drop right back into the shift crank. Will / can the shift crank move thus make me take the entire lower section (prop shaft, drive shaft , ect...) out to get it back together? Or is it a simple lift out and set back in (nothing tends to be that easy on these things.) I am going to wait until I hear from one of you before I lift it out..... it seems like it is all but inviting me to simply lift it out then it will be a PITA to get back together. Any info? Thanks

 

[Racerjoe]

This is alpha 1 gen II

 

[porscheguy]

This is the part I was referring to.
http://www.marinepartshouse.com/mercruiser-alpha-one-shift-shaft-bushing-seal-p-759.html

And this is the special tool to install

https://m.overtons.com/modperl/prod...MI15_nk5Tq2QIVA0wNCh3sNwTLEAQYBCABEgLQhPD_BwE

 

[Racerjoe]

Thank you Sir!!!

I think those are from pre gen II as mine do not look like that. I was able to come across a Mercruiser factory manual on another site that said it could be done so I pulled it out and was able to get it back in after swapping the shift shaft bushing...

 

[Racerjoe56]

It turned out to be the shift shaft seal so I replaced the entire bushing/housing and did the water pump and the driveshaft seals under it. No more leaks....... Thanks you guys!!!!