Alpha 1 gen 2 bellows service

MBAKER · Saturday at 10:22 AM

What is recommended service interval for this? Safe to assume it would be longer For a boat trailered and stored inside year round? When these do fail is it a slow leak where you start to notice water and bilge running or is it going straight down if not caught.

JustJason · Monday at 1:42 PM

There is nothing in print other than "inspect yearly".

The rule of thumb is that if they are OEM bellows and not aftermarket, 5 years is the expected life span.

When they fail, it will start as a slow leak that will get exponentially worse as the tears grow in size.

Scott06 · Monday at 2:13 PM

X2 I inspect yearly. My 2004 boat the OEM ones lasted 18 years and still were not leaking- fresh water lift kept boat.

Given that lifespan of the OEM parts doesnt make sense to use aftermarket unless you are selling it

Lou C · Monday at 3:36 PM

I tilt it up and use a bright flashlight to check for cracks in the folds, as soon as you see that, the rubber has gotten oxidized and hard and is now due for replacement. I get at least 10 years out of OEM Cobra bellows.

cyclops222 · Monday at 5:32 PM

I always store all OB and sterndrives in the full down position. All are original.

Lou C · Tuesday at 5:09 AM

The bellows should definitely last longer if the drive is stored down. I'd use OEM for the bellows for sure, and for impellers as well.

drewm3i · Tuesday at 5:13 AM

In my experience, the OEM ones last for at least 15-20 years if stored properly. My 30 year old boat is on its second set that were replaced in 2018.

Scott06 · Tuesday at 10:27 AM

Lou C said:
The bellows should definitely last longer if the drive is stored down. I'd use OEM for the bellows for sure, and for impellers as well.

Due to where I use and store my boat the drive is 3/4 to all the way up almost all the time and I got 18 years out of them…

Lou C · Tuesday at 12:50 PM

It’s good to know that because for some that’s the only option.

Scott06 · Tuesday at 2:11 PM

Lou C said:
It’s good to know that because for some that’s the only option.

yep I'm in that group. Have a holist but its in 25-27" of water. I leave the boat on a trailer, when I used to leave it in an old barn you parked it outside and the owner moved them in at his convenience. For $12/month storage who cares... My father built a 3 bay garage where it winters now but he may need to pull it out for one reason or another and I take the battery out so its full up all winter.

Bt Doctur · Tuesday at 9:04 PM

when you decide to replace the bellows CUT the oil line before removing the hinge pins and remove the hoses using a razor knife gently on the transom side
You DO NOT want to break the plastic fitting for the oil fitting on the transom side.

drewm3i · 2025-08-27T03:43:06-0600

Bt Doctur said:
when you decide to replace the bellows CUT the oil line before removing the hinge pins and remove the hoses using a razor knife gently on the transom side
You DO NOT want to break the plastic fitting for the oil fitting on the transom side.

I have done that once lol! I was able to replace it without removing the engine but it was a *****! I was like 21 or 22 at the time and was made of rubber.

Alpha 1 gen 2 bellows service

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