Problem with my lower unit?

[Zim]

Hey everyone, I have an 89 mercruiser with the alpha one on it... bought the boat used so I dont know exactly what happened, but the previous owner told me theres a problem with the outdrive or possibly prop hub. The symptoms are these:

Out of gear the prop just spins freely (this is normal right?)

When I put the boat into forward gear I can spin the the prop in the forward motion by hand, but I feel a slight resistance on every revolution. The prop will not turn the opposite way though, so I cant spin it both ways.

In reverse its the opposite as forward where I can spin the prop by hand in the reverse motion, but it wont budge if I try spinning it in the forward motion.

This doesnt seem like a prop hub to me because it wont spin both ways while in gear. Whats it sound like to you all?

 

[Haut Medoc]

Re: Problem with my lower unit?

The prop hub has nothing to do with the lower unit other than is is bolted to it.....
That said, with the boat in gear, engine off of course!, you should not to be able to turn the prop counter -clockwise ......
It will turn clockwise while in FWD .....
The reverse is true for, well, reverse....
You should not be able to turn the prop clockwise while in reverse, once it initially catches.....
It should spin free either way in neutral....
You cannot tell if the prop hub is spun visually or by hand.....
Pray it is the prop hub, they can be fixed rather easily....
I would pull the prop, run the engine on muffs & see if it shifts correctly.....
Welcome to iboats, btw........JK

 

[Zim]

Re: Problem with my lower unit?

Ok, well I already pulled the prop off, then tried spinning that shaft with just a wrench and I can do the same thing with the wrench as I can with the prop on there, and everything feels the same. Sounds like I have some bigger problems. I can feel the resistance, its like the gear teeth just arent quite all the way matched up. This snow needs to melt so I can get the thing started. And it does engage in gear, Ive got a gut feeling that I need to replace the lower unit of the outdrive.

 

[Haut Medoc]

Re: Problem with my lower unit?

Nope..... that clicking is normal....
Did you read & follow what I posted above?
When in gear, (either fwd or rev), the shaft will not turn one way & will turn the other way & click slightly...
Swich gears & it will be the exact opposite....
This is normal!
Like I said, run it on muffs & shift it into gear & see what happens....
Beware of freezing weather, if you do not know how to winterize & you should wait.....
I think you are worrying to much....
From what I am hearing, you are OK.....
The prop?
Well, one thing at a time.....
Here is something for you to read while waiting for the spring thaw.......http://www.boatfix.com/merc/Servmanl/6/6covr3.pdf

Post your engine serial # , it sounds like you need a manual for that, too.............JK

 

[Zim]

Re: Problem with my lower unit?

Thanks for your help, yeah thats exactly what it was doing when I put it in gear, it would click but not turn the opposite way of the gear I was in (i.e. wouldnt turn counter-clockwise when in FWD). Im glad this is a normal thing I need to find a heated garage so I dont have to re-winterize it. Im trying to get it fixed up for a trip down to arizona here in a month, thats why Im sort of pressed on time. Once the weather stops getting to freezing temps at night ill probably hook the muffs up and see what I can find out. If that kind of stuff seems normal what might I be looking at for a repair?

When I bought it he said that there was some sort of problem. Said he was crusing and all of a sudden the boat just started slowing down until it was stopped. Said he'd put it in gear and it would rev up, but not go anywhere. Any thoughts?

 

[ziggy]

Re: Problem with my lower unit?

generally, the first thing that comes to my mind if it revs and goes nowhere is either the spun prop hub. or a coupler.......
to check for the prop hub ya can paint the prop and the hub with something. run it. if the lines are still lined up, it aint the prop hub. i'm no pro so the way i'd think ya could check for the coupler would be to pull the drive and look at the splines where the enter the coupler. and look inside the coupler witha light to see how thems splines are. if it goes nowhere. and it aint the prop. you might not have any splines though. hope that aint the case.......that's my 'guess'.....

out of courisity, what engine goes with yer alpha1?

man. it's gonna be -8* here in a couple of nights here in lincoln. you aint that far away...pretty cold for workin on boats. hope yer garge works out.....

 

[Zim]

Re: Problem with my lower unit?

Thanks for the reply, the alpha one is attached to the 4.3L mercruiser in a 19' monterey bowrider. I picked the thing up for $650 bucks with a tandem axle trailer and everything. The seller claimed the motor starts up and runs fine, all the guages work, lights work, trailer had surge brakes, all that good stuff. The only things wrong with it are what I've been describing and it needs a little cosmetic work on some of the seats and panels in the boat. I'd like to see if it is a spun hub before I start tearing anything apart if possible. Also, being new to this whole boating thing, I'm not even really sure what the prop hub is on the thing lol. Ive just done some searching and found it to be a common problem. Can you shed some light on what the prop hub is and what I actually need to mark on to test and see whether or not it is a prop hub? Here's a picture for any reference you can give me... This is what I've taken off the boat when removing the prop, this is everything:


First picture is exactly how it came apart. Last piece to come off on the left, first piece to come off on the far right of the photo:

Heres some other pictures:

Everything at least LOOK normal?

 

[ziggy]

Re: Problem with my lower unit?

i think the blue line is the prop hub. the red line is the prop. if when it's in the water and ya throttle up. and the slip occures. if themz lines aint still together. then the hub is spun...
prop looks normal to me. a little dinged up perhaps. i think you have the thrust washer still in the prop also. unless it's still on the propshaft. just went and looked at my alum. prop. with the thrust washer removed you can see the splined sleeve better from the front side of it.

sounds like yer gettin ready to start workin on boats to me. you should get yerself an oem service manual for yer rig....it's a real big help.....

 

[andy1canada]

Re: Problem with my lower unit?

"Problem with my lower unit?"

Actually Zim, I think you got this problem posted in the wrong section; if ya scroll down a little further on the forum menu page you'll see the heading 'Erectile- disfunction'... ya' otta' find help for yer' unit there...

Good Luck!

Terry

Victoria,BC
Canada

 

[Haut Medoc]

Re: Problem with my lower unit?

He should visit the "Marble Arch".....
That would fix it!.....

 

[HT32BSX115]

Re: Problem with my lower unit?

Terry may be mistaken.....


Unless you find something obvious, you'll have to put it in the water to properly load the drive system to check it. You cannot check it properly on "muffs"

get a manual, ensure that the drive oil is properly serviced and not got water in it...You may find that the coupler is indeed "spun" Sometimes there will be a black rubber "powder" in the bilge.....(or chunks).....the result of "spinning" the rubber part of the coupler.

When it happened to my older Mercruiser 150 it wasn't the rubber part at all. The internal (metal) splines actually stripped.

It didn't happen all at once either. It was ok at slow speed but would initially "slip" at high speed and during acceleration.

After a short period of that it stripped out completely. It was ok at idle but only idle.....after a few min at idle it would not turn the drive at all. When I removed the coupler there were NO splines at all in the coupler.

The coupler was only 40+ years old (1966 model boat)......I suppose it lasted many years longer than it should have!


You'll have to remove the engine to check/replace the coupler



Cheers,



Rick







.

 

[Haut Medoc]

Re: Problem with my lower unit?

I doubt if your coupler is shot on an '89...
Start where I asked & proceed from there...
Read the link....
When you have some more questions.....
Post....
As Reel Poor says.....
"Only the Wise "............
Don't worry, be happy!

 

[Zim]

Re: Problem with my lower unit?

"Problem with my lower unit?"

Actually Zim, I think you got this problem posted in the wrong section; if ya scroll down a little further on the forum menu page you'll see the heading 'Erectile- disfunction'... ya' otta' find help for yer' unit there...

Good Luck!

Terry

Victoria,BC
Canada

Hey, I'm only 23... I dont quite have those problems yet ya crazy Canuck! d

 

[Haut Medoc]

Re: Problem with my lower unit?

8) Think before ya post...
Us old guys will help ya!d

 

[Zim]

Re: Problem with my lower unit?

8) Think before ya post...
Us old guys will help ya!d

Yeah I appreciate it very much. Im one of those people that are pretty mechanically inclined, Im just new to this whole drive system. I have a built up Mustang that has taken most of my free cash before I fell upon this boat, so Im happy to have another hobby. You guys have been great so far, its nice having forums that have helpful people on them out there 8)

 

[Haut Medoc]

Re: Problem with my lower unit?

8) If yer lucky, your boat will be fine.....
Patience....:"Gashogger"....'Err...."Grasshopper."...

 

[andy1canada]

Re: Problem with my lower unit?

Hey Zim!

Forgive my transgression; no harm intended.
The title of your post just brought out the goof in me.

Best wishes with your new boat!

Cheers,
Terry

 

[rebars1]

Re: Problem with my lower unit?

Hey! If you thought the Mustang took your free cash, wait until you really dig into the boat!

 

[Zim]

Re: Problem with my lower unit?

Hey Zim!

Forgive my transgression; no harm intended.
The title of your post just brought out the goof in me.

Best wishes with your new boat!

Cheers,
Terry

No worries, I could tell you were joking.

 

[CaptRon66]

Re: Problem with my lower unit?

In addition to marking the prop/hub you may have access the drive shaft and engine coupler. You could mark them too. My brother spun a engine coupler on his Mercruiser 165. That engine is now in my boat. The rubber melted on his. Smoke ,burnt rubber smell and noise. After i took the boat off his hands I could see the drive shaft turning at a slower rate that the engine. I had a spun prop last summer that would slip while turned hard by hand. It got me home keeping the rpm's under 1200 to prevent slip. It must be much harder to check for slip by hand if the problem occurred at higher rpm.