stern drives...

[Blue_Heron]

Since the subject came up recently, I've got a question for the experienced stern drive guys. I disassembled my Bravo transom assembly this evening. It was apparent that the seal on the upper swivel pin was bad. The steering arm and swivel pin were pretty badly rusted. I intend to replace both.

So my question is whether I should go with the stock swivel pin or get a stainless one. I'm concerned that using stainless could shift the point of corrosion from the pin to the aluminum gimble ring. If that's the case, next time around I would be replacing a gimble ring instead of a swivel pin.But what do I know? The lower swivel pin is stainless, so maybe it's a non-issue. Anyone got experience using the stainless upper swivel pin on a salt water transom assembly?

Thanks,
Dave

[pelican]

Originally Posted by abl1111

Agreed. On a new drive - and I HATED to paint it the first time, I would use a Green scotch scrubber. But, once you have painted it, you can use either or. Either way, I'm not talking aggressive sanding - light with 120 or so - I want to remove the oxidized paint. Where metal shows, I sand it to bright aluminum so the primer has a better chance to stick.

When you paint a never before painted drive with antifouling - no matter how you prep it, there will be areas that will come off in 'sheets' - 1/2" or so after a season... These need to be feathered and a scotch pad ain't gonna cut it. Whenever possible, don't use sandpaper, but at some point, it will be needed.

that's not true - the antifouling paint,it will come off - as far as the paint on the drive it self - it will not - granted,it will "wear",in the skeg area,from hitting the sand,but that's it - the drive in the pictures i posted - that's the original drive,the paint has never peeled on that drive,or any other drive i service - again,the paint i'm referring to,is the paint,on the drive,from the factory.and again,pressure washing,is definatley the way to go,followed by scotch brite pad - granted,a few barnacles may cling,especially,if the boat hasn't moved for a while - most of the time,these can be pressure washed off...

it's best not to "disturb",the original paint on the drive,the trim cylinders and the transom assembly - this can and will allow corrosion to get a "foothold",it also leads to the original paint popping off - which will lead to the entire drive needing to be stripped,chemically etch primed and refinished - the only way to repair that situation permenantly...

[pelican]

Originally Posted by Blue_Heron

Since the subject came up recently, I've got a question for the experienced stern drive guys. I disassembled my Bravo transom assembly this evening. It was apparent that the seal on the upper swivel pin was bad. The steering arm and swivel pin were pretty badly rusted. I intend to replace both.

So my question is whether I should go with the stock swivel pin or get a stainless one. I'm concerned that using stainless could shift the point of corrosion from the pin to the aluminum gimble ring. If that's the case, next time around I would be replacing a gimble ring instead of a swivel pin.But what do I know? The lower swivel pin is stainless, so maybe it's a non-issue. Anyone got experience using the stainless upper swivel pin on a salt water transom assembly?

Thanks,
Dave

only ones i've ever used,are the standard pins from merc...

[abl1111]

Pelican,

I will defer to your judgement - you definitely seem to have a lot more experience with mercruiser I/O's.

I am very happy with the condition of my set-up... Just not the work each spring to get it there...

Wish I had a boat lift !

[hiliner222]

Originally Posted by pelican

i think you might wanna check that cooling system again - i don't think merc manifolds are freshwater cooled.

the cooling passages will erode - the gasket surfaces erode too - mercs are not as prone to this,later model mercs - they use a "dry joint" system...

those MPI'S with the horizon package - like the one you have,is it new as in 2011 ? if so,it would be equipped with catalytic converters - to pass the emissions standard ...your engine cat equipped ?

There is a closed cooling system and a half system. The half system flows fresh water through the engine only the full system does the manifolds also with block off gaskets at the risers. On a full system salt or raw water only passes through the risers and out the exhaust. You can plmb the mercruisers either way.

[jnamowitz]

I have a question in regards to the alpha one gen 2... I have changed my ujoints and Gimbal bearing due to a knocking. It doesn't happen at full trim or at any turn angles, just when it's in gear. The previous owner said it has been that way for a couple years. It's not a severe banging, just a clicking when the boat is placed in gear. Any ideas?
Thank you in advance.

[Fr. Frank]

71 Seafari, Mercruiser 140. Current motor block indicates it was manufactured in 1986/7, but has all 1971 electrical and ignition stuff. Original transom group and original M/R outdrive. Installed all new seals last fall, all new bellows, new lower cable, new hoses, new manifold and new exhaust riser/elbow.
We live in Florida, so "winterizing" is unnecessary. HOWEVER, after many years in the marine industry, I have an annual "maintenance list" for a sterndrive.

JANUARY 1
Remove drive
Change water pump impeller, inspect pump housing and wear plate.
Remove propeller
Inspect seals, bellows, u-joint, drive shaft
Lubricate, lubricate, lubricate
New outdrive gaskets and o-rings (never re-use)
Change Lower unit oil.
Clean and re-grease prop shaft

I would say that with proper flushing, raw water cooled manifold, risers/elbows, and t-stat housings are good for 6-7 years. But ya' gotta flush the motor for a period of time AFTER it gets to full operating temperature. Salt-away isn't enough, nor is 5 minutes running at idle with a cool motor. But eventually, these pieces WILL need to be replaced