Alpha One Stern Drive

[Mc14tider]

I have a 1998 3.0L merc cruiser. I changed the stern drive oil and topped off the reservior. While out on the lake today when we stopped to swim I saw a small oil slick around the back of the boat. Looked at the reservior and noticed it was almost empty. I filled it, went back to the lunch and it was down below the lower level line. Chaeck the stern drive while in the water and out can’t see any leaks. Any help would be appreciated.

 

[simonfraser]

if you're losing fluid you got a leak
if you can't see it with the boat in the water take it out

 

[dpb]

How did you fill the stern drive with the new oil?

 

[MapisM]

It's been a while since my last Merc outdrive boats, but I would have sweared that the Alpha has no reservoir, only the Bravo does.
Can you post a pic of that reservoir?

 

[mlines]

Did you fill the drive from the top or bottom (bottom is correct). If the top then it is full of air, hence the dropping oil level.

 

[rafiki_]

I had a pair of Alfa 1 Gen 2’s on a previous boat, and like MapisM I don’t recall a reservoir. Generally Merc Alfa’s are very reliable.

 

[KDee]

I had a pair of Alfa 1 Gen 2’s on a previous boat, and like MapisM I don’t recall a reservoir. Generally Merc Alfa’s are very reliable.

Bought an Alpha1 Gen 2 in 2014....definitely had an oil reservoir.

 

[spannerman]

As a Mercruiser engineer I can confirm Alpha have had reservoirs for many years, my 97 model Alpha has one since it was new. If its leaking oil in the water it can be either a fill or drain plug loose, or the hose from the shield to the gimbal housing is cracked/ loose.

 

[benchmark]

After owning one myself up until 3 years ago, I can confirm that the Alpha 1 gen II has a reservoir.
After servicing and filling the gear oil it is not uncommon for the level in the reservoir to drop after a few days of shaking as the air locks get filled.
I won’t panic, just make sure that your gear oil drain screw and washer on the drive leg are not leaking, fill up the reservoir again and keep an eye on it. You may be lucky that the oil slick you sat in was not from you own boat . Keep us updated.

 

[QBhoy]

Hi

probably what’s going on here...if you are lucky and what usually happens...is if you have been patient enough like you, to let the whole system drain down including the reservoir, then after you have filled the gearbox from the bottom up, then filled the reservoir again, there is always an air gap there between the top vent level of oil in the drive and the header tank. It can take a good while for the level to settle and the void space taken up. It will then show the true level. It often can take a few outings for this to settle and a few top ups along the way.
hopefully the sign of oil you initially saw in the water is just from the usual mess made with oil running down the side of the leg after it comes out the vent. Or grease excess from when you greased the leg or prop shaft. That would be perfectly normal.