View Full Version : scotts donzi

06-06-2012, 05:45 AM
looking for an owners manual for a 1988 25' ragazza, or info on somewhere i can download one. Thanks in advance...

06-06-2012, 07:29 AM
Don't waste your time. There really weren't any manuals that were worth anything. The boat manuals were nothing like a car's manual. The ones they issued with boats had generic boat handling and safety information.

Your best best would be to buy service manuals for the engine and drive that you have. They come from Merc or Clymers or others. They will give you information you can use.


06-06-2012, 01:26 PM
+1 on Tidbart's comment. I got my 28 brand new from the factory and the manual is worthless... it covers the entire ZR and ZX product lines as an all in one manual and it's thinner than a magazine. Some manufacturers to a better job than others. Donzi builds a great boat but have horrible documentation. Formula, Viking, and Ocean Yachts I can vouch for their excellent documentation so it does vary.

06-17-2012, 05:49 AM
Sure appreciate the heads up, I've used Chilton, etc. with automotive so I'm familiar with going that route... You both saved me some time. Thank You...

06-17-2012, 05:56 AM
Ok, next question, 3rd time out on my "new" old 1988 25' ragazza, I have some outdrive experiance, while throttling up I had the drive more or less slip out of gear, as I throttled back it caught and away I went, seems as long as I gently throttle up there is no problem, How hard is it to adjust the clutch? or is this the wrong forum.....

06-17-2012, 08:32 AM
The coupler is shot and needs replaced. The rubber doughnut inside the coupler has broken loose from the steel casing and is slipping.
The engine and drive have to be removed. The coupler is bolted to the flywheel, and the input shaft is splined into the coupler.
A suggestion......replace the Alpha coupler w/a Bravo coupler. They are completely interchangeable except for the older flywheel cover. After about '90 or so, all the flywheel covers are identical and include a larger hole in the rear surface to give clearance for the larger Bravo coupler.

Good luck w/the new boat.

06-18-2012, 03:36 AM
If the coupler is shot wouldn't it slip all the time? Thats why i thought the clutch just might be slipping because of an adjustment, Or is it wishful thinking on my part....who wants to pull an engine....ever.

06-18-2012, 06:49 AM
No, not necessarily. The rubber doughnut either shears through the rubber itself, or at the joint of the rubber and the steel housing. It may hold up to 2500 RPM or so, I've had that experience.

Alphas use a dog cluth, which are ratcheting metal to metal devices. They don't slip in the sense you're speaking of.

06-18-2012, 10:25 AM
Here is some reading for you.



Not the same as your setup, but the same principles apply.

Good luck. Bob

06-18-2012, 12:50 PM
George Carter is most likely correct about your engine/drive coupler slipping~~~
This is the typical failure mode you described.

Also if your propeller has a rubber splined shaft hub almost the very same thing can happen.
I have seen dozens of rubber splined shaft hubs in propellers slip as the prop hub gets older or is over torqued..
The rubber will have torn loose in the hub.
Usually you will see a black stickey rubber substance oozing from behind the prop's mounting washer & lock nut.
If your prop does have a rubber shaft hub I would first try pulling & replacing your prop with another known good spare.
That would be the first easiest thing to try~~~
If you still have the very same slipping problem it's sadly then time to pull the engine & outdrive and replace that worn-out engine/drive coupler as George Carter suggests.
George sure knows his boats, drives, & engines !

06-20-2012, 07:11 AM
Well I can't thank you guys enough, I have a plan of attack now, I have spun 2 props in my time and this is now looking like the damn coupler.... Boat = B ring, O out A another T thousand...right....I get back out to the marina this thurs. I'll do a little testing and let you know what happens, thanks again, I think, hahahahaha
Oh, one more question, looks like the coupler is connected to the engine only, why do you have to pull the outdrive? I've never been in that far before... Thank you.

06-20-2012, 08:08 AM
The drive shaft, which is attached to the outdrive, goes into the coupler, which is attached to the engine. So, you have to remove the drive in order to remove the engine.


06-20-2012, 11:10 AM
As others have already mentioned~~~
A failed & slipping outdrive coupler will usually smell like burning rubber in your engine comparment while it is actually slipping.

A slipping rubber propeller hub will not produce any smell since it is running under water.

Did you smell any burning rubber smell while the slipping was actually happening ?
This would give you a good clue if it is in fact the drive coupler; or instead the prop hub that is actually slipping.

06-23-2012, 12:56 AM
silverghost, I did not smell any burning rubber, Do you agree GCARTER? Could it be good news???

I went out to the boat Last Thursday, while in the work rack I put the drive in gear with the full forward motion on the Throttle/gearshifter... jumped down and tried to rotate the prop...I could not budge it.
While turning the prop CCW I had the clicking sound which Gcarter was talking about with it being a "dog clutch" that was obiviously the the dog clicking on the gear teeth.

The guy I bought it from gave me the original prop so I'm going to try that first, (it has a stainless steel on it now)

06-23-2012, 08:19 AM
When mine failed, there was no smell, but then I thought I knew what it was, so I didn't abuse it.
Like I previously mentioned, it would drive up to a little over 2000 RPM before starting to slip and I was able to get home.
If you find it is the coupler, I'd encourage you to replace it w/a Bravo coupler.
You'll likely never replace it again.

06-23-2012, 08:45 AM
I would agree with GC on the coupler maybe something in the drive. a slipped hub on a prop can't be babied or finesed to work as normal, once a hub is gone the problem only gets worse idle speeds are the best that can be done . I had quite a few hubs go and I never had one I could get on plane.
good luck getting the issue resolved.

joseph m. hahnl
06-23-2012, 09:18 AM
Are you sure it's not just cavitating out of the hole? Tuck the drive all the way in when throttling up. Prop hub is the easiest to check. The Hub assembly should be interchangable if they are Mercruiser props.Note the stainless prop will not flex like an aluminum prop,they are unforgiving to rubber parts.There is no possible way for you to determine whether it's a coupler or a prop hub ,turning it by hand.Think about it, your turning 200+ horses before it slips.The prop or coupler would have to be completly played to turn it.Also the engine would most likley spin before either. You would need at least, a extremely long lever ,and a piston stop.

06-23-2012, 10:19 AM
Joe, yes cavitation would fit with the babied or finesed throttle work

06-23-2012, 11:13 AM
I went out to the boat Last Thursday, while in the work rack I put the drive in gear with the full forward motion on the Throttle/gearshifter... jumped down and tried to rotate the prop...I could not budge it.
While turning the prop CCW I had the clicking sound which Gcarter was talking about with it being a "dog clutch" that was obiviously the the dog clicking on the gear teeth. I believe this above is a key clue, I don't think it's the prop or coupler, I believe your shift cable is kaput or out of adjustment... with the gearshift in fwd., you should have no CCW rotation.. just my .02 and i've been wrong before...

06-26-2012, 05:55 AM
Tried that other prop... ran w/no problem but only two of us in the boat, had it wide open, about 35 mph. @4000 rpms seemed to be ok??? spun prop??? G Carter... you seem to know where the bear **** in the buckwheat, what do you think? My next move is more people in the boat(weight) and another try...I'll let you know.

06-26-2012, 07:38 AM
It seems you may have a poor prop selection to work with.
If you were able to go to full throttle, then it's unlikely the coupler.
I had a number of props on my Minx that wouldn't work at all. They would blow out when the throttle was advanced, and required you to come to a complete stop to restart.
The two props that worked best on THAT boat were a Turbo I tried, and the prop I ended up with, a Hydro Q4 which was a 21" x 15.5" which never, never blew out.
Your boat is larger and heavier than my former boat and there're many variables to consider for proper prop selection.
There was a former member here that had a twin of your boat w/a very healthy SBC that would actually hit 60 MPH.
Maybe some here could make suggestions as to a shop that can give guidance and maybe some props to try.

06-27-2012, 04:21 AM
I'll def. try that Mr. Fixx, G Carter these posts are making me feel better and better all the time, Now with the cavitation train of thought, I do have the trim tabs, and I did work on getting my trim guage calibrated a little better so I do know where my prop is. Also. G your right on another note, the stainless was a faster prop. but the original (alum.) put the boat on a plane quicker.
Buizilla, that was my first thought when the problem started, I was thinking slipping clutch. Gcarter had explained about the dog style clutch. I'm really thinking , With all of you guys help of course!, I have a combination prop and cable adjust problem. Gcarter , I will research what is the right prop and write down the pitches I do have on these two. I will also try to learn something about the cavitation issue....
God Bless you all, I will keep going till I getter done!

07-10-2012, 12:34 AM
Had to be cavitation... the stainless was a 14.5 X 17, the previous owner told me he had just put it on, only ran it once or twice with no real throttling done, I put the michigan wheel on it and it runs a little slower but it sure seems A-ok, the only numbers I could find on it were 2010 16.... But the pitch and dia. were way different. went to a prop shop, they looked up and found the all around prop for that should be something like a 15 X 19??? any thoughts? Thnx again

07-10-2012, 02:16 AM
I only skimmed, so apologies in advance if I misread this.

But if you're looking for a Michigan Wheel 15 x 19 stainless, I think I have two of them for sale. (Came off my alphas during my current Cig 24 repower.) Feel free to PM if interested. No worries if not, and/or if I misread something and have this hopelessly wrong. :)