Alpha one swivel shaft seal

[shibbs]

I’ve discovered that I am suffering from a slight weap from the swivel shaft seal on the Alpha one ( gen 1 ) drive leg. Coupled to a 5.7 merc V8.
Anyone on hear any experience with replacing this part?
I understand from some
Guidance on US forum that it can be done with engine in ( more challenging but no cost of removing an engine tht has only just gone in) or engine out.
I’d rather leave the engine in for a number of reasons but at present, don’t have a lot of know how on how this job is done.
Absolute Sod’s law thT a job arises that needs the engine out after it has only just been out!!

[Cap'n Jack]

Hi Shibbs

I had this done by a marine engineer , there was a dribble of water from it and it was identified as the Swivel Shaft. It definitely can be done without removing the engine as Mecruiser/Quicksilver make a kit for it. It's a bit ugly as there are two large plugs in the transom assembly but after a while they pale into insignificance. Sadly I don't have details of how to or the kit, however if I remember it right, the kit explains how to do it.

This is from an Alpha One PDF Manual

Gimbal Housing Access plug.pdf

(547.55 KiB) Downloaded 354 times

[Ianfs]

I've been trying to remember why it's either engine out or drill large holes in the Gimbal housing. I think its because there is no access to the shaft nut from inside the boat. Mercruiser obviously knew this was a problem so provided a kit. It's called a Gimbal Housing Access Kit. There are loads available in the States or Aus but I cant find one in the UK. This is what you need. Mercruiser part no 22-88847A1

https://www.crowleymarine.com/parts/301034.cfm?gclid=EAIaIQobChMIjZLkw_2e8QIVF853Ch0_RgJVEAQYASABEgIk5fD_BwE

You get two plugs and a new nut. I found an old post on the YBW forum where I posted this instruction from Mercstuff, someone had asked the same question on the Sportsboat & Rib forum as well. This talks about a Gimbal Ring repair kit but they are mega bucks and you don't need these bit in the kit apart from the bungs and nut. You can buy new swivel shafts so I would go with that as well.

http://www.mercstuff.com/gimbalringinst.htm

If I remember anything else I'll let you know. But no 100% you do not have to remove the engine

[shibbs]

That’s great info, really useful, thanks very much.
Not sure if I’m going to tackle this myself or get a ‘professional’ in.
Trouble is, I have no idea who / which marine engineer will be able to do the job.

[Ianfs]

I've now found out why you cannot access the nut on top of the Swivel Pin from inside the boat. It's because the Transom is in the way.

When the hole is cut in the Transom for the Transom Shield (inner housing) to be bolted to the Gimbal Housing (outer housing) it has to be a certain size, but it's not big enough so that the Swivel Pin nut is accessible from inside the boat. You would think you could cut a small bit out to get to it , but not so sadly.

Taking off the leg and the bell housing reveals the Gimbal Ring attached to the Gimbal Housing. The Swivel pin is the top pin to which the Gimbal Ring is attached to the Gimbal Housing. It's nut attaching the Swivel Pin is inside the top of the Gimbal Housing so getting at it means cutting a 1 1/8" hole either side of the top of the Gimbal Housing.

Some say you have to undo the nut by using a screw driver on the edge of the nut flanges with gently encouragement from a hammer, but others say yo can just get a spanner in there.

Either way, once you have cut the holes, have access to the Swivel Pin and managed to undo the nut, the pin will drop out.

Employing someone to do it, for me would be ringing round the Marine Engineers in your area and asking them if they had done one previously. If no, move on to the next one. Some of them do invoice more than the actual hours worked, which includes chatting to the wife or taking other bookings on the phone and then of course there is the working out what to do next if they haven't done this sort of thing previously.

There are some really good caring engineers out there though but it's finding them and they are usually very busy.

[shibbs]

Thanks for that info and detail Ian, kind of you to take the time.
I think I will monitor it for now, she will be coming out in about 6 weeks anyway due to work commitments.
It’s very very slight at present so should be ok for a few more weeks.
I mY make a start to it myself over the winter, see what I can do..
the theory behind it sounds fairly simple.. famous last words!
At least it means tht while it’s apart the rest of the drive and housing can have a full service with new bellows, bearings etc

[Ianfs]

Sounds good to me Stu, good call.