Prop / prop shaft damage

Kwanza

Cadet
Joined
Mar 6, 2026
Messages
29
Hi, I had an unfortunate series of what I thought small incidents recently.
5.2 m Glastron MX175 runabout, with VP sterndrive.
1. Upon returning home with my boat and parking it, I manually pushed the trailer to back it up in my driveway and hit and scraped my timber fence with my stainless-steel prop. Snails pace, fence quite rickety as well. Used boat as expected after this, with no issues noticed.
2. At the boat ramp, I mucked up, and hit the bottom of the ramp (concrete), with my stainless-steel prop, barely above idle. I continued my trip, and upon return I had very minor chips/scrapes on 2 out of 4 blades. Minor, I would say, 1 mm. Attempted to fix it with very fine sandpaper. Used boat as expected after this, with no issues noticed.
3. And yes, I engaged in retrieving boat at the ramp without lifting drive. Stopped the car immediately when I heard the scraping, might have dragged it a meter or less. Bottom of the skegg scraped slightly, not broken, no bend I could notice. I checked prop, it was spinning both ways in neutral, don't know whether pre-incident was spinning easier or not.

Following this, during my next trip I completed an ~10 km journey after this incident. Everything seemed to work ok, had to engage both forward and reverse gears to leave the marina, and completed an ~12 km trip. Then engine cut out. Could not restart it. Would turn over very-very slowly, maybe one turn, struggling. No click from starter motor. Battery showing 12.4 V. All gauges (charge, oil, temperature) indicating correct values. Attempted start with a jump starter pack the Coast Guard had with them, and while it definitely had more juice than my battery, would only do the same. Turn over one or twice very sluggish, forced. Engine has oil, did not overheat, it was in the nominal range throughout.

Now home, I inspected my prop and tried to manually spin it.
In neutral, spins easily in the reverse direction, and I can barely turn it over in forward direction. I wobble it back and forth a bit, turns in forward direction with increasing resistance, no noise, but not a smooth turn. I can almost feel some sort of grinding, but no noise.
In reverse gear, it spins easily in reverse, and locked when I attempt forward spin.
In forward gear, locked when I attempt reverse spin, and the same seizing, hard forward turn.

Is it possible that a small damage done earlier now became a critical issue, and my engine would not start because it knows it can't run safely, as it can't spin the prop shaft?

I'll be taking it to the mechanic, unless there are any suggestions I could try.
My shifter cable is not the smoothest, but from the above it seems the shifting itself is working.

I just read about hydro lock now...possible.
Trying to rotate the engine by hand at the crank/flywheel - not budging. Or barely.
My engine oil (on the dip-stick) was clear yellow/amber color when I checked straight after stalling, it is the same now. Need to see what's in the bottom.

Thank you.
 
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Kwanza

Cadet
Joined
Mar 6, 2026
Messages
29
Removed spark plugs. All four dry. Tried turning the engine at the front, where the belts are, I can turn it over manually, quite hard but turns over.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
14,526
I suspect that the Gearcase is low on Oil and the Upper Gears/Bearings were starved. Most VPs have a Hexagonal Bolt/Screw a the top of the Outdrive housing. It will also be a Dipstick. Remove it and see if there is any Oil on it
1784786391593.png
 

Kwanza

Cadet
Joined
Mar 6, 2026
Messages
29
I suspect that the Gearcase is low on Oil and the Upper Gears/Bearings were starved. Most VPs have a Hexagonal Bolt/Screw a the top of the Outdrive housing. It will also be a Dipstick. Remove it and see if there is any Oil on it
View attachment 418221
Thank you.

Not only was it bone dry, I could hear the hiss of the air rushing in as I was opening the hexagonal bolt of the dipstick. I will next check the drainplugs for any residue/metal shavings. The boat was serviced in April, and I paid for Gearcase oil, gearcase O ring, and O ring top gearcase dipstick.
I presume the moral of the story is to really check all your fluids as per the manual. I did check engine oil twice lately, but no gear oil. After all, it was just replaced.....was my thinking. I don't think I'll try to do anything else with it until my mechanic has a look.

Removing the bottom drain plug, there were no residue stuck to the magnetic bolt, but some oil came out. Maybe ~25 ml, still seeping out when I put the screw back. Oil was clear, not milky, no residue or suspensions of any kind. Will eventually drain all to see how much is missing.
Thank you.
 
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