Hi everyone. long time listener, first time caller. I feel like I have searched as many threads as I can and I’m feeling pretty stumped. This is my first boat and I'm soaking in all the knowledge I can.
I recently bought a 1977 Glastron with an OMC 235 HP I/O. I checked all the fluids and took her to the lake. She fired up easily and we cruised for about three hours with no issues aside from listing starboard a little when not at cruising plane. Near the end of the evening we were moving along at about 2200 RPM when we heard a loud whine and immediately lost thrust with the engine revs out of control along with a bit of smoke and rubber smell….. I throttled back and tried several times to engage forward or reverse and neither had any thrust and neither gave the standard “thud” when engaging. Shortly thereafter the engine began to overheat and spit coolant out… it seemed obvious that the impeller was no longer working either. We got a tow back to the dock and made it home, pulled the plug and a good amount water and antifreeze drained out.
I’ve read that this is quite common so I’ve gone through the following steps and I’m hoping someone can point out what I’m missing. Thanks!
1. I read forums for days…… then
2. Downloaded the manual….
3. Looked for rubber beneath the engine and could not find any but there’s all kinds of gunk and liquid still there.
4. Inspected ball gears which appeared mildly worn but not damaged.
5. With battery on and outdrive fully down-
Engaged full forward and turned the prop CCW which I was able to do with medium pressure. Prop turned freely CW.
Engaged full reverse and turned the prop CW which I was able to do with medium pressure. Prop turned freely CCW.
6. Removed the prop and repeated step four with the same results.
7. Opened the upper gearcase to find milky oil (it wasn’t milky before the trip). I couldn’t immediately identify anything out of the norm otherwise.
8. Removed and inspected lower gear case at a basic level. Fluids and components looked good.
9. With it reassembled I put the outdrive down into a container of water and started the engine and could not get any action out of the outdrive just like at the lake.
10. Removed the outdrive per the manual but I left the shift wires connected and kept the outdrive grounded to the intermediate.
11. With the battery on and gear all the way forward I secured the outdrive ball gear and tried to spin the prop shaft CCW and I could not. This makes me think everything in the outdrive is good aside from the seal letting in water to the upper gearcase.
12. Trained intermediate though almost nothing came out until I pulled the driveshaft out and then maybe a cup or two of fluid.
13. Removed and inspected driveshaft. Bearings all appear good and the spline teeth are covered in rust but the teeth are still intact.
14. Flash light and tool probing of coupling through the intermediate and I can see lots of rust powder and the teeth appear to be worn in the middle but look good on each end. I can feel the teeth with the wire probe.
15. I re-insert the driveshaft, battery on, and try both forward and reverse as I turn the driveshaft in both directions using a wrench. The teeth grip without issue and I can hear the engine compressing the air through the carb.
16…… come here and post this.
What am I missing… I don’t want to pull the engine to inspect the coupling if its strong enough to turn the crankshaft then what has gone wrong? Thanks for your time!
I recently bought a 1977 Glastron with an OMC 235 HP I/O. I checked all the fluids and took her to the lake. She fired up easily and we cruised for about three hours with no issues aside from listing starboard a little when not at cruising plane. Near the end of the evening we were moving along at about 2200 RPM when we heard a loud whine and immediately lost thrust with the engine revs out of control along with a bit of smoke and rubber smell….. I throttled back and tried several times to engage forward or reverse and neither had any thrust and neither gave the standard “thud” when engaging. Shortly thereafter the engine began to overheat and spit coolant out… it seemed obvious that the impeller was no longer working either. We got a tow back to the dock and made it home, pulled the plug and a good amount water and antifreeze drained out.
I’ve read that this is quite common so I’ve gone through the following steps and I’m hoping someone can point out what I’m missing. Thanks!
1. I read forums for days…… then
2. Downloaded the manual….
3. Looked for rubber beneath the engine and could not find any but there’s all kinds of gunk and liquid still there.
4. Inspected ball gears which appeared mildly worn but not damaged.
5. With battery on and outdrive fully down-
Engaged full forward and turned the prop CCW which I was able to do with medium pressure. Prop turned freely CW.
Engaged full reverse and turned the prop CW which I was able to do with medium pressure. Prop turned freely CCW.
6. Removed the prop and repeated step four with the same results.
7. Opened the upper gearcase to find milky oil (it wasn’t milky before the trip). I couldn’t immediately identify anything out of the norm otherwise.
8. Removed and inspected lower gear case at a basic level. Fluids and components looked good.
9. With it reassembled I put the outdrive down into a container of water and started the engine and could not get any action out of the outdrive just like at the lake.
10. Removed the outdrive per the manual but I left the shift wires connected and kept the outdrive grounded to the intermediate.
11. With the battery on and gear all the way forward I secured the outdrive ball gear and tried to spin the prop shaft CCW and I could not. This makes me think everything in the outdrive is good aside from the seal letting in water to the upper gearcase.
12. Trained intermediate though almost nothing came out until I pulled the driveshaft out and then maybe a cup or two of fluid.
13. Removed and inspected driveshaft. Bearings all appear good and the spline teeth are covered in rust but the teeth are still intact.
14. Flash light and tool probing of coupling through the intermediate and I can see lots of rust powder and the teeth appear to be worn in the middle but look good on each end. I can feel the teeth with the wire probe.
15. I re-insert the driveshaft, battery on, and try both forward and reverse as I turn the driveshaft in both directions using a wrench. The teeth grip without issue and I can hear the engine compressing the air through the carb.
16…… come here and post this.
What am I missing… I don’t want to pull the engine to inspect the coupling if its strong enough to turn the crankshaft then what has gone wrong? Thanks for your time!
