84 Sea Ray Monaco - Bent Prop Shaft.

[84Monaco]

I know there are a lot of posts about this topic, but I haven't found any exactly like mine.

I have an 84 Sea Ray Monaco I/O with a 280HP 350CI V8 and mercruiser Alpha One (I think). I've had it for a couple of years, and it has a bent prop shaft - I think it was this way when I bought it but I didn't realize right away. It's just far enough out that you can see it when you spin it by hand - not too bad, but undeniable.

The thing is in great shape otherwise and runs well. Gear lube looks good - changed it twice (seasonally). Doesn't seem to be leaking. I've been running it for two seasons this way, and while it does vibe a bit at certain low RPMs, it seems to run just fine.

If I don't want to put the money into a rebuild or a new lower unit, should I be worried that I'm going to ruin more things? Like I said, its been running like this for some time, and while I would like to fix it I don't want to drop the $$ into it right now.

Thanks for your advice!

 

[JustJason]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

If I don't want to put the money into a rebuild or a new lower unit, should I be worried that I'm going to ruin more things?

Yes.

Acceptable runout is something like .010. In other words... if you can see it with your eye, then it's bad.

Thanks for your advice!

What advice are you looking to hear? You already know the part is bad.... so i'm ASSUMING ya know that your running on borrowed time.... correct?

 

[Don S]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

If I don't want to put the money into a rebuild or a new lower unit, should I be worried that I'm going to ruin more things?

Nothing more than the price of a new outdrive.

 

[84Monaco]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

Has anyone out there had a similar situation? What more would be damaged then the outdrive?

As far as I can tell it would probably just wear the bearings faster than normal and eventually start to get play and leak.

Does anyone out there think it would be cheaper to rebuild with a new shaft than to simply replace the lower unit?

 

[Bondo]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

Does anyone out there think it would be cheaper to rebuild with a new shaft than to simply replace the lower unit?

Ayuh,..

The Cheapest way out is to tear it down, have the shaft Straightened,+ reinstall everything....

 

[jaxnjil]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

realy you need to take the prop off and then put a dial indicater on it and see what your true run out is
with out that any thing else is a guessing game

 

[84Monaco]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

Not looking for step-by-step or anything, but how much work is this? I've done a lower end engine rebuild and have set up a new ring and pinion gear on a Jeep rear end. I'm not a master mechanic, but I'm not afraid of getting into it.

How many hours would I end up putting into this and what manuals/supplies/special tools would there be to buy?

Thanks!

 

[jaxnjil]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

when you put the price of SEI stuff + there 3 year no fault warranty it makes it hard to spend much on labor for this type of job.
price both and you will get the answer that fits you best



here is the link for i-boat it is 695

http://www.boatmotors.com/motorparts/index.cgi?pid=7528&flag=2&year=1984&state=fl

 

[achris]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

Just fixed one for a friend. Acceptable limit is 6 thou. His was 60 thou! Removed the prop shaft and using a pair of vee blocks, a dial gauge and a press we got it to 5 thou.... Re-installed the prop shaft and all is well....

DON'T keep running with this problem. It'll cost you about $50 to fix now, or about $700 later.... Your choice.

Chris........

 

[jaxnjil]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

don has provided the manuals to you free of charge but you still need the speical tool and parts.
if your not paying someone then you might come out a head.
off hand i think they get 600 to 650 or so here on i-boats for a SEI new lower replacement

 

[abj87]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

If you can set up rear end gears you can do this. Just follow the manual, tells you every thing you need to know.

 

[84Monaco]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

don has provided the manuals to you free of charge but you still need the speical tool and parts.

Where can I get the manuals?

 

[jaxnjil]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

they are in the adults only sticky that don put at the top of this forum

i made a spanner and puller to get mine apart so i didnt have to buy. just went and looked to take a pic for yu but cant find them now.

 

[84Monaco]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

Jaxnil - any luck finding that picture? I'm thinking about getting started on this.

 

[84Monaco]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

Thanks for the help so far! I'm trying to figure out exactly how to approach this. Let me know if I'm on the right track.

After a little research I believe I have a Mercruiser 260R with a transom SN of 6693455. On the drive itself it says 1.50R and 6693357.

On a related issue, I know it is good to replace the impeller - I don't know when it was last done and I've had the boat for 2 seasons. If I'm reading things correctly, the impeller is accessed pretty quickly once you start disassembling the lower unit.

Is there a place I can get all of the supplies I need as far as new O-rings, the impeller itself etc. for the lower unit? I know on auto pumpkins you can get a "master installation kit" with all the shims/seals etc. that you need when you're changing gear ratios.

Can anyone point me to a source for a kit like this?

At the risk of broadening the thread, it sounds like as part of routine maint. I need to drop the outdrive completely to inspect and lube the shaft splines and gimbal bearing, alignment.

Do you think it would be best to pull the lower unit first and do the upper stuff without the additional weight or should I pull the whole thing off and then separate upper from lower?

Another somewhat related but different thing: I've never owned one of these so it's all new to me. Is it normal that the sound of the drive gets louder and harsher when turning sharply under load? Once I get it all open is there something specific I should be looking for or is it normal?

Thanks in advance for all your help!

 

[84Monaco]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

Any thoughts? I'm thinking I'll start by pulling the lower unit and tearing into it...

 

[Fishermark]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

Pull the whole outdrive off as a unit and then take it apart in halves.

The water pump impeller is a simple job while you are there.

The harsh sound when turning could be your u-joints or gimbal bearing. Check the gimbal bearing for smoothness and if there is any question on the u joints I would suggest changing them out while you have it out

You will also need to check the engine alignment with the outdrive off so you will need to buy an alignment tool. Don't worry - you will need to use it more than once, so it will pay for itself.

 

[84Monaco]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

I don't have the press, etc. to try to straighten the shaft. Would you guys recommend that I just see if a local machine shop will try it?

I talked with a local marine service center and they said it would probably be sketchy to try to straighten it, and that even if they could it would probably cost a couple hundred bucks.

I can see how this could get pretty quickly more expensive than just putting a new lower unit on - at least at the $695 price...

I think I'll see what luck I have finding a machine shop willing to give the straightening a try before pulling things apart...

 

[84Monaco]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

So I pulled the lower unit and got the water pump out. At which point I realized I needed some specialized tools...

Have you guys had luck getting the bearing carrier retainer out without the special wrench? Did you just drill and chisel it out like the manual suggests or is there another way?

Then what about the drive shaft nut wrench and the pinion nut adaptor? Special tools for cars seem fairly easy to come by or borrow, but looks like these boat ones are pretty steep!

Do any of you have tips for fabricating tools or any other tips for a poor man's way to get the drive/prop shafts out of the lower unit?

Thanks!

 

[84Monaco]

Re: 84 Sea Ray Monaco - Bent Prop Shaft.

Well I found a local shop that was willing to pull the shaft and straighten it if it is inside the specs they consider safe for straightening.

I asked them about checking engine alignment as well and they said that if I pull the upper unit, they'll go ahead and check the alignment and reinstall everything on the boat for the same price, which seemed like a good deal.

So...I pulled the upper unit tonight and found fresh green gear lube in the bellows - I've read about it on the forum...

It's making this look more and more attractive.

http://www.sterndrive.cc/Merchant2/...plete&Category_Code=MercruiserAlphaSterndrive

Have any of you had experience with these? Would you recommend? What would you do in my situation?