Slickcraft sterndrive quit

[Jerome Lowery]

My grandson has a 1972 19' Slickcraft boat with a 188 hp 302 Ford engine. Had it on the lake running smooth then it just quit. The engine runs fine but the prop quit turning. Now out of the water, checking finds starting the engine and moving shift/throttle fwd engine revs but no shaft turning. Shift to neutral, engine stalls every time. On the transom inside, there is some type of looks like a hydraulic tank with solenoid and wiring (marked use engine oil). No idea what it's for. I would really like info on this problems, especially the one on the sterndrive not engaging at all. The prop just spins freely. I really don't think there is mechanical problems with the sterndrive. THANK YOU. Jerome....

 

[thumpar]

What drive?

 

[Jerome Lowery]

Mercruiser is all I know.

 

[thumpar]

It is probably either a spun coupler or broken vertical shaft. Don't run it like that because the impeller isn't turning. The tank and pump if for the trim/tilt.

 

[Jerome Lowery]

Thank you for the response. I guess this means a disassembly to try to find the problem....

 

[H20Rat]

Pull the outdrive off first, it is really easy to do, just follow the videos for it. once you have that off, spin the driveshaft by hand and see if the drive turns.

 

[Jerome Lowery]

Thank you.

 

[Bondo]

Ayuh,.... Welcome Aboard,.... Movin' this to the Merc I/O forum for ya,....

 

[Jerome Lowery]

I'm an old gearhead from the 60's. All I am trying to do is to help my grandson's boat going. No one seems to want to work on this old boat. I am not a boat mechanic. I have turned many wrenches in my day, still do on occasion. I have destroyed a few standard transmission and differentials. When something broke, there was NO doubt in anyone's mind that something broke. Now how can people say that this or that is broken in the sterndrive unit, when the thing just sits there. No movement at all, no noise, no gears growling or shafts banging around. NOTHING.... Just sits there, doesn't even try to move. I don't mind taking it apparent, but I sure would like to hear a logical reason as to why something is broken inside the unit. Thank you. Jerome

 

[thumpar]

The coupler is not on the inside of the unit. It is on the back of the engine. If it strips the drive doesn't turn. Normally everything in the drive is spinning except for the very bottom where the clutch dogs engage for reverse or forward. If you have access you could look at the shaft that goes from the engine to the drive and see if it spins as the engine is spinning. If it is not spinning the coupler is bad.

You have to understand that the people here have done it for years. What sounds logical with a car has nothing to do with boats other that the basic way an engine runs.

 

[Jerome Lowery]

I understand about cars/boat difference. Thank you the response. I will check it out.

 

[Grub54891]

If you just take the top off the drive, remove the 4- 3/8 12 point bolts, and take the cover off, you might find the top gear set stripped out. Usually from low oil in the drive. I have 3 units in the shop right now with the same issue. No, not mine....lol

 

[Pete104]

Don't tear it apart until you have to.
Jreome, take a "sharpie" and mark a line on the prop install hardware and on the hub of the prop itself. You may see 3/8"-1/2" material that a silver sharpie will mark. Put control handle in forward gear. Full throttle, don't matter, just atleast fwd gear. Turn the prop counter-clockwise.
Report back, please.

 

[thumpar]

A spun prop hub would still turn the prop shaft and make noise going into gear.

 

[Pete104]

Thumper, I really think that they are not out of panic mode yet! Gramps wants to help the grandson out! Are you suggesting pulling the the drive now?

 

[Grub54891]

I agree with thumper, I still think the upper is shot. It's just 4 simple bolts, no need to take the drive off either. If you find the gears are good, just make Shure the o-ring is good, and put it back on. Torque to 30 lbs and investigate further later if need be.

 

[thumpar]

Thumper, I really think that they are not out of panic mode yet! Gramps wants to help the grandson out! Are you suggesting pulling the the drive now?

Yes. It would only take 10 minutes. It is not just a spin prop hub. There are other things that need to be checked out with the drive off too.

 

[Pete104]

Well, Gramps should have been there to check the gear oil then.
I was blind sided by 1 of these old prop units ONCE! It won't happen again!!!

Good luck Jerome! & family

 

[Jerome Lowery]

I really appreciate the the recommendations. I will show my grandson the suggestions. Will try them when I can tie him down. He's one heck of a worker. Will report back. Thank you. Jerome....

 

[Jerome Lowery]

No Title

His boat