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Tidbart
05-08-2011, 01:16 PM
Went out for a cruise yesterday. Everything went well, did 75 miles.
Until........Let Lulu drive for a bit, just cruised across the lake at varying speeds from 30-60 mph, just to give her her first lesson in driving. Went well.

We stopped about 1000 yards from the entrance to the inlet that leads to the ramp. I took over and idle most of the way in. I decided to speed up some and when I put the throttle down, the boat started to move and then some kind slippage occurred and the boat would not go faster regardless of rpms. Slowed back to idle and tried it again, and again. Nothing.

Fortunately, the boat still moved forward in gear and I idled back to the dock.

Things look for?? Check the rubber hub on the prop. If that is OK, pull the drain plug and check the fluid for filings???

Sound like the correct first steps??? Suggestions appreciated.

Bob

silverghost
05-08-2011, 01:29 PM
Prop rubber hubs often shrink & slip as the props get old.
Swap props & re-test
Also~
Check the outdrive's shift cable for proper adjustment & It's proper shifting and drive clutch operaton.

Carl C
05-08-2011, 01:43 PM
Does sound like a spun hub. Try another prop or mark yours and see if alignment changes.

silverghost
05-08-2011, 02:20 PM
Usually when these prop hubs start to slip~~~
They start to slip at the same engine RPM.
This is the torque where the rubber will break-loose.

If you continue to use that slipping prop the rubber will melt and he maximum RPM where the prop will slip will slowly drop.

Look for stickey & gummy rubber inside the prop's hub.

Don't just toss-out your old prop~
A good prop repair shop can usually press-in a new rubber center hub.
The old Volvo 270-280 replacment hubs are getting hard to find~ If any here have an older Volvo drive ?
The new replacment Bravo hubs are a very easy & cheap repair job.

mrfixxall
05-08-2011, 02:25 PM
Seaweed?? could be one cause..next time out try putting it in reverse then forward,,could have been a little slop in the shift cable..

like said already..pull prop off and inspect the hub,,it you have a flotorqur hub pull the guts out in the prop and inspect..

Tidbart
05-08-2011, 02:41 PM
Got some time this afternoon. Will pull the hub and see what she look like and go from there.

B

Tidbart
05-08-2011, 03:42 PM
Here are a couple of photos.

The center black section tapped out rather easy. I would think this is supposed to be bonded to metal hub?

Does the metal part have to pressed in/out?

B

Tidbart
05-08-2011, 03:45 PM
Now that I think about it, I was going about 40 and hit a gator about 20 minutes prior to this problem starting. This might have started to break the hub loose.

No, I am not kidding.:anchor:

B

silverghost
05-08-2011, 04:37 PM
The rubber hub in that prop is designed to absorb vibrations & act as a sheer device .
Similar to an old fashoned sheer-pins.
When you hit that gator that hub probably saved your outdrive & engine by sheering & breaking loose..

I wonder how well that ol gator survived that propeller strike ?

Poor Gator~~~
I was not his day !

Carl C
05-08-2011, 04:58 PM
I spun one hub in my lifetime and it was on a Merc 200 OB. It didn't hit anything. It let go with no warning and the boat would only move at idle speed. There was also no visual indication of any problem with the hub. I knew what it was because that is the only thing that can slip without making noise. I had it repaired. On an outdrive I think the only other possibility would be the coupler.

Whoa, just saw the gator post! Mark the prop and hub and see if the marks move. The problem is not always visible.

MOP
05-08-2011, 05:00 PM
The insert is suppose to come out easy it is just an adapter, try another prop see what happens if all is well just get that one re-hubbed.

Ghost
05-08-2011, 05:04 PM
Now that I think about it, I was going about 40 and hit a gator about 20 minutes prior to this problem starting. This might have started to break the hub loose.

No, I am not kidding.:anchor:

B

Adding "have you hit any gators recently?" to standard diagnostic questions...

silverghost
05-08-2011, 06:09 PM
In Philly here we don't have to worry about hitting any gators on the Deleware river~~~
Just floating telephone pole sized logs, , dead mobsters & ex- street gang members.
They are called "Floaters" around here .
Every spring ~~~When the water warms-up just after the spring rains~~~
they come floating up to the surface .

gcarter
05-08-2011, 07:19 PM
I suppose a coupler would be noisy, I remember mine was.
But the outcome was similar as it wluld pull no faster than 2100 RPM.

mrfixxall
05-08-2011, 08:21 PM
Here are a couple of photos.

The center black section tapped out rather easy. I would think this is supposed to be bonded to metal hub?

Does the metal part have to pressed in/out?

B


post a pic of the piece that goes in before the prop nut..it should lock in the 4 slots and and have splines in the middle of it..im wondering if the piece in the center whoich may still have splines in the middle may have broke..if its a solid hub then that piece that slid out may just be a spacer..

http://www.go2marine.com/go2_structure/9/1/8/2/91822F-f.jpg (http://www.go2marine.com/go2_structure/9/1/8/2/91822F-f.jpg)

Buddyc
05-08-2011, 09:06 PM
In Philly here we don't have to worry about hitting any gators on the Deleware river~~~
Just floating telephone pole sized logs, , dead mobsters & ex- street gang members.
They are called "Floaters" around here .
Every spring ~~~When the water warms-up just after the spring rains~~~
they come floating up to the surface .
wow you put your boat in that river... I wouldn't put my mother inlaw in there.

Tidbart
05-08-2011, 10:56 PM
post a pic of the piece that goes in before the prop nut..it should lock in the 4 slots and and have splines in the middle of it..im wondering if the piece in the center whoich may still have splines in the middle may have broke..if its a solid hub then that piece that slid out may just be a spacer..

http://www.go2marine.com/go2_structure/9/1/8/2/91822F-f.jpg (http://www.go2marine.com/go2_structure/9/1/8/2/91822F-f.jpg)

It appears to be a solid hub. Looks like I have to go further.:frown:

B

Tidbart
05-09-2011, 07:50 PM
Went a did some checks today. Visually, can find no issues with the prop, prop shaft, splines. Put it in gear, turned with breaker bar and engine turns.

Pulled the drive oil drain plug, no metal on the magnet.

Got a look from above at the coupler area. No metal shavings nor rubber strewn about, at least on the outside where the shaft enters the rear of the coupler.

Next......

gcarter
05-09-2011, 08:25 PM
Went a did some checks today. Visually, can find no issues with the prop, prop shaft, splines. Put it in gear, turned with breaker bar and engine turns.

Pulled the drive oil drain plug, no metal on the magnet.

Got a look from above at the coupler area. No metal shavings nor rubber strewn about, at least on the outside where the shaft enters the rear of the coupler.

Next......

Bob, my one coupler experience produced no shavings or fur balls of rubber. It just made a horrible juddering sound and feel when the torque exceeded the sheer limit.

MOP
05-09-2011, 09:32 PM
It does not look like a solid hub to me, the rubber is between the outer and the square. It also does not appear to have let go, you usually can see a bit black gooey of rubber in the grove. Most any prop shop can torque test it, it should hold over 600 lbs.

Phil

VetteLT193
05-12-2011, 01:47 PM
It appears to be a solid hub. Looks like I have to go further.:frown:

B

Bob, does your setup match what is above? Mainly the brass end part is long and slides into your prop?

I'd also check the brass piece. That part is the single thing that holds the whole setup together. All of the torque runs through it, and I could see where it might have gotten messed up with a hit. See if when you slide it on the shaft that it bites well and nothing is sheared. Normally the plastic insert should blow first but it's only a 2 second check.

I've also seen a forgotten washer (the big brass one) cause some interesting results.

if all that checks out, put the prop on, put it in gear, and try to turn the prop. the plastic insert might look ok but still be slipping around in there.

Tidbart
05-12-2011, 02:16 PM
Hi Bob,

If you look at the middle photo that I put in post #7, you can see the part of the hub that is removable. I did eventually knock it out.

Unlike the one that Fixx posted, I had the high hp version that has 4 thin round strips of rubber that are in between that removable piece and the permanent hub. The thing about this type of hub is that although it has rubber strips, it is considered a solid hub. The square piece and the rubber are just for minor shock absorption like when you put it in gear.

Anyways, yesterday I took it to a prop shop along with some other props that needed cleaning. Spoke for some time with the owner, very knowledgeable. Result being, it is not the prop and hub. No signs of rotation and in essence it can rotate anyway. The plastic insert is just a spacer to fill between the smooth part of the prop shaft and the prop. I performs nothing else.

So, after some more conversation he said if the clutch pack went, I would not have been able to move. He points to the coupler. On one side, the coupler is probably 3-4 hundred and a lot of my labor. On the other side, the clutch and gears are about 1400 plus someone else's labor. Let's hope it is the coupler.

Mike, prop guy showed me another replacement hub that I can put in that prop. See photo.

My guess is the coupler.:crossfing: Will probably start taking it apart next week after my drive stand shows up. New toy.:yes:

B

gcarter
05-12-2011, 03:57 PM
You'll love the drive stand.
Everyone should have one.

mrfixxall
05-12-2011, 05:30 PM
before you take anything apart, drop the boat in the water again,drop it in gear and see if you can duplicate the problem..if its the coupler it will make smoke in the engine compartment and that would be a dead give away,when they slip it creates heat and will melt the rubber back together so you will have to try and make it smoke on the water..also if your shift fork is worn in the drive it will take about 5-1o seconds to drop into gear after putting the drive in gear,this is also a common ware item on a bravo drive..check all the bolts on the back cap to see if they are loose,snug them to 20 ft lbs of tq.

Tidbart
05-12-2011, 05:38 PM
before you take anything apart, drop the boat in the water again,drop it in gear and see if you can duplicate the problem..if its the coupler it will make smoke in the engine compartment and that would be a dead give away,when they slip it creates heat and will melt the rubber back together so you will have to try and make it smoke on the water..also if your shift fork is worn in the drive it will take about 5-1o seconds to drop into gear after putting the drive in gear,this is also a common ware item on a bravo drive..check all the bolts on the back cap to see if they are loose,snug them to 20 ft lbs of tq.

That was going to be my next step after I get the props back. I will most likely strap it down well to the trailer, back it in and run it. I will not have a tow boat with me, if needed.
As far as shifting, there was no hesitation, but I will double check it.
After that, I am considering going to talk with a Merc drive expert in St. Cloud and see if it is worth bringing in the drive and have him go through it. At the very least, see what he has to say. Obviously, if that is good to go, it has to be the coupler.

B

VetteLT193
05-12-2011, 10:18 PM
if you need props, hubs, whatever just let me know and I'll drop it in the mail. I have a 25, 23 Mirage + with hub... both the rubber style you have and the new delrin style hubs.

i also have 24, 26 bravo props...

The way you keep your stuff it would blow my mind if your drive needed going through.

my guess at this point is with most others... coupler. knowing the engine has been out I'd yank one more time, do the coupler, align it to the hilt (as only an engineer could) and rock on... and no more gayterds! :anchor:

Tidbart
05-13-2011, 08:08 AM
Anyone know the difference between the hub that I show in post #22 and and the Delrin style (Flo-torq II)?

They must have some max HP rating, I would think.

B

Tidbart
05-13-2011, 08:16 AM
if you need props, hubs, whatever just let me know and I'll drop it in the mail. I have a 25, 23 Mirage + with hub... both the rubber style you have and the new delrin style hubs.

i also have 24, 26 bravo props...

The way you keep your stuff it would blow my mind if your drive needed going through.

my guess at this point is with most others... coupler. knowing the engine has been out I'd yank one more time, do the coupler, align it to the hilt (as only an engineer could) and rock on... and no more gayterds! :anchor:

Thanks Bob, I will keep it in mind about the props. Should be good to go for a while on those.
I am not going to go through the drive necessarily. Would just like to pick the brain of Craig Colabella. From what I understand, he was the Lake X drive guru for Merc and he has a shop in St. Cloud. Good to know.
B

CHACHI
05-15-2011, 01:41 PM
Bob, when my engine coupler went a few years back, no smoke, no noise.

I was in gear idling, pushed the stick forward a bit, not hard, boat started to rise and then fell back down. Took all the splines out of the coupler.

Motor was out of alignment. Further investigation showed that the engine mount/stringer bolts were too long from Donzi, (it is a '99).

The nut would bottom on the threads before you could get the bolts tight enough.


Ken

mrfixxall
05-15-2011, 02:38 PM
If it turns out to be the coupler get the HP one with steel splines..They last about twice as long as the aluminum spline one..

Tidbart
05-16-2011, 08:06 AM
Bob, when my engine coupler went a few years back, no smoke, no noise.

I was in gear idling, pushed the stick forward a bit, not hard, boat started to rise and then fell back down. Took all the splines out of the coupler.

Motor was out of alignment. Further investigation showed that the engine mount/stringer bolts were too long from Donzi, (it is a '99).

The nut would bottom on the threads before you could get the bolts tight enough.


Ken

Ken,

Sounds exactly like what happened to me. I will most likely start the removal this week after the drive stand gets here.

B

Tidbart
05-16-2011, 08:12 AM
If it turns out to be the coupler get the HP one with steel splines..They last about twice as long as the aluminum spline one..

Planned on the HP one after learning of the Al. splines. Steel all the way.

Turns out, through some correspondence and research that the Merc couplers are made by Lord Corporation. I will be talking to a boat guy who sell them today. If all is well, I can save a few bucks and get the same unit, just not pay for the name.

Bob

Tidbart
08-13-2011, 10:33 AM
Well, it has been a while since this issue came. I have forgotten to give an update, so here it is.

I pulled the motor and replaced the coupler. The old one really had no sign of wear visible from the outside. See photo.

While I had the engine out, I decided to freshen up the transom assembly and drive which was the next step in my refreshing of the boat. The transom assembly and drive are a whole other story.:wink:

Anyways, as far as the coupler goes, I eventually got the transom back together and reinstalled the motor, aligned it, got the drive back on. Took it for a test drive and found it was the coupler after all. :yes:

I couldn't be happier with that result... it was not the drive.