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Mercruiser outdrive

Now I'm really confused, I was told that if there is a "A" stamped on the end of the prop shaft it is a alpha lower unit. Now you are saying that it is a bravo outdrive.
 
the "A" was to designate between the R and MR drives(I think)
Most of us can tell the drive just from looking, did you view that link in post 7, Alpha drives are the link in post 14
 
Hate to say it, but I think I need to take this in to a mercury service dealer. Have then go over the whole outdrive, and tell me what needs done. I'm pretty good at working on every other part of the boat, but the uncertainty of the outdrive tells me to have a pro work on it. Any idea what a dealer will charge to go over the outdrive, and replace the wear out items. Thanks to those that helped, but if I would have started with all original parts, I wouldn't hesitate to dive in and work on it. But I have no idea what has been stuck together here.
 
You have a Bravo drive that is almost bullet proof. there is no impeller to replace and unless its leaking oil there are only some O rings to replace.Not much for a dealer to do .
 
Now I'm really confused, I was told that if there is a "A" stamped on the end of the prop shaft it is a alpha lower unit. Now you are saying that it is a bravo outdrive.



Stop listening to whom ever you are listing to...........

There is no way you have an Alpha drive or part of one.

They absolutely positively do not mix and match..........

forget the letter A on the prop shaft............it is there for another reason.....for which I forget right now.


Again

You have a BRAVO outdrive.

Other than seal leaks about the only thing that goes wrong is the shift linkage in the upper gear case and the cone clutch wears out. This will be obvious when under power and it wont shift in to or out of gear (as long as the shift linkage is adjusted correctly)

Bravo's also DO NOT SHIFT when not running. So if you try to shift out of gear and sometimes into gear when parked at your house and it does not shift that is normal. Once you start the engine and the drive starts to spin it will shift.

Use ONLY high performance Merc gear lube!!!!!!
 
Thank you Jack. I fully believe what your telling me. But I very got questions, I have no gear drain hole in the bottom of the prop hub, which I read as a bravo 1. Mine is on the side like most that I've ever worked on in the past. Does that make it a bravo 2 lower? And I read that the water pump impeller is in the front of the motor (belt driven), and that should be changed yearly, correct? And is this something a normal plant maint. person like myself should be able to replace? It also has the oil reservoir mounted on the transom inside. It's currently empty. And there is a small amount of oil down in the bottom of the cavity going into the outdrive, something I can fix, or take it in?
 
drain hole can be in the carrier, left side or right side. where the drain is does not make it one type of drive or another. the drive is Bravo , most likely a Bravo 1.Having the larger impeller in the engine driven pump, you can go 2 years depending on certain factors.
As far as the mechanical factor, if you can change a spare tire, you can change an impeller.
A drive should never lose oil once properly filled. A pressure test is in order to check the drives integrity.You will have to remove the drive and check the main bellows for oil. oil in there is a input shaft seal or yoke issue.
The Bravo drive link will have the necessary info.
 
If the reservoir bottle is empty that could indicate a problem.


As said the only way to tell is to have it checked out.

first is to remove the drive from the gimbal housing,
then inspect the U joint bellows for gear oil.
if gear oil is present then most likely you have a upper carrier seal leak, (common with use and age)

The specific way to determine this is to empty the drive of oil, the pressure check the drive to ~ 15 psi. It should hold this pressure for 2 minutes. (drive must be off boat)

This actually should be done anyway as the boat is new to you. You want to be sure everything is in good condition.

I pressure check every outdrive I service regardless.

A side note, when a drive is emptied and refilled, if the reservoir is full to start, once the drive runs the reservoir will empty almost 3/4 of the way. This is the nature of the system. Once emptied refill to line. Then this should stay this way for ever unless there is a leak.

Running a outdrive with an empty reservoir is a NO NO........if the gear oil is leaking out past a seal then the UPPER gear case will be starving for gear oil and the bearings and gears will get ruined.

As this boat is new to you and you are unsure, I would either bring it to a trusted boat tech or if you have a mobile tech available see if he can come to you.
If a mobile guy can come to you then you can observe what he is doing and possibly ask some questions.
At least I never minded answering questions..............


We here can only answer so much. The real answers will be seen first hand if properly tested by someone who understands what they are doing.

Good luck!
 
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