My Bottom

[argonaut]

On my Alpha leg ... the bellows cam off mid season .......... as per Mercruiser Tech note, refitted and it was 'glued' in place (hull side) with a Mercruiser adhesive.

Never came off again.

[Bigplumbs]

Looking at the first pictures of your stern drive it looks as if you have mostly algae growth with a few smallish barnacles, so the anti foul must have done some good and if you had moored with your leg up, the sunlight would help the algae too. Glad to hear you got it off though.

I read in one of your "other" posts that someone thinks by having your exhaust bellows disconnected it will sink the boat, either he hasn't read your post properly or he's a numpty who wants to add to his post scores!

As Martin (alias Mike ) has said, Mercruiser do supply and fit a straight fit exhaust tube to Bravo Three but I don't think they have vented props similar to those fitted to the Bravo Ones and Alpha drives. Also I seem to remember they were made because quite a few exhaust bellows were coming off Bravo drives, like yours came off the Alpha. Ian read about anti cavitation gases going through the prop, but I think he is talking about the above, i.e. Mercury's Performance Venting System. Some props (I can't see them on yours, its ali not stainless) have vent holes enabling exhaust gases to be vented (not cavitated) through the holes at hole shot. This allows the props to spin up more quickly and doesn't allow the engine to baulk, but instead gets the prop revving and once there is sufficient water flow over the prop holes, the gases are directed through the prop. The production of 4 and 5 blade props seems to have taken its place except where a fast Bass boat owner wants a fast 3 blade propeller, although my Laser II has vent holes but they are a real pain at slow speeds.

Although you probably don't want the extra work Dennis, if your drive was worked on 2 yrs ago, don't you think it might be worth a look see inside it just to check for corrosion, leakages, gimbal bearings ok etc? The genuine gasket kit is only about £12-£15 so not dear and you could inspect the impeller whilst you are at it. You'll be all ready to go next season then without any worries.

Thanks for the info and all good advice. I may take the drive off later in the year but I tend to be a person who adds a year to things rather than subtracts one.

For example my friend always does his impellers every year. I tend to do mine every 2 or 3. He changes his oil and filter every year I sometime leave it 2 years etc.

I know this is the wrong direction for some but it is the way I am. I think it comes from having far too much stuff to maintain and I try my best to do it all my self. Currently I have:

6 or more boats to look after
1 Jet Ski
220 radio control planes (That is not a typo it is 220).............. Mad I know
5 cars
1 caravan
1 swimming pool
6 Sheds
4 Lawn mowers
3 Strimmers
8 Trailers
1 House
1 Pond
1 little dog
1 Black mental cat
2 Chain saws
and Her indoors who wants some chickens

All my fault I know but it is a lot to keep on top of....................

Dennis

[shibbs]

I think your over doing it... The cat needs to go!!

[Bigplumbs]

I think your over doing it... The cat needs to go!!

But she was here first and as Her indoors says all black cats are mad so she is a kindred spirit

[betty boop]

You're missing a camper van / motor home and there are no motorbikes either,

[mlines]

but I don't think they have vented props similar to those fitted to the Bravo Ones and Alpha drives.

They do, the exhaust vents through the props. The "trumpet" style bellows, whilst not glued, slides over the sterndrive tube when the drive is lowered. Whilst there is an escape of gasses around the tube, a reasonable amount still vents through the props,

[betty boop]

but I don't think they have vented props similar to those fitted to the Bravo Ones and Alpha drives.

They do, the exhaust vents through the props. The "trumpet" style bellows, whilst not glued, slides over the sterndrive tube when the drive is lowered. Whilst there is an escape of gasses around the tube, a reasonable amount still vents through the props,

what about mercathode continuity ? from what I just read voltage or earthing runs through the grounding tabs on the bellows

[betty boop]

but I don't think they have vented props similar to those fitted to the Bravo Ones and Alpha drives.

They do, the exhaust vents through the props. The "trumpet" style bellows, whilst not glued, slides over the sterndrive tube when the drive is lowered. Whilst there is an escape of gasses around the tube, a reasonable amount still vents through the props,

what about mercathode continuity ? from what I just read voltage or earthing runs through the grounding tabs on the bellows

[mlines]

I thought the grounding tabs on the bellows were purely to include the metal bellows clamp in the circuit, otherwise the clamp is isolated by the rubber of the bellows. I thought the main continuity was provided by wires connecting the major parts.

[Bigplumbs]

You're missing a camper van / motor home and there are no motorbikes either,

Ahhhh I forgot to list the motorbike. I have a Kawasaki GPZ1100