Hello everyone!
I haven't posted here in a while because I have been pretty busy with my job. Occasionally I do get a chance to take the boat out though.
I have a 1992 Sunbird with the Cobra 4.3 I/O.
I noticed the other day that my cavitation plate on the port side was bent up. No other immediate damage noticed.
I figured the only way that could have happened was if a log got caught between the prop and the cavitation plate.
The last time I had it out with my brother we were cruising pretty slow probably about 5 mpg on the Missouri river and we both heard a "thump" from the rear.
It definitely must have been when it happened however I didn't see any logs in the vicinity of the boat at the time.
Well today while planning my attack of straightening the bent cavitation plate, I decided to check the prop and prop shaft. I can visually see that the prop shaft is off center by looking at the threaded prop nut and spinning the prop by hand.
The bearings feel ok. If I stop the shaft on the "high" spot that seems the most off center,...and check the prop blade opposite of it I can tell I have a blade bent back about a half inch.
So now I know for sure something got caught in there.
The shaft looks like it almost has about an 1/8" runout on the very end. Nothing is rubbing anywhere though.
I realize that running a bent prop shaft can cause vibration, which I have noticed, and early seal and bearing failure.
I am fully capable of replacing the shaft but I am wondering if I do so will I have to do any re-shimming of the drive gears in the back?
Also, there isn't much boating season left here in Omaha, NE and I was wondering if it might be OK to run it until winterization. Then pull the lower unit and do it over the winter season.
Here is a couple pictures.
Thanks for any input.
Chris.
I haven't posted here in a while because I have been pretty busy with my job. Occasionally I do get a chance to take the boat out though.
I have a 1992 Sunbird with the Cobra 4.3 I/O.
I noticed the other day that my cavitation plate on the port side was bent up. No other immediate damage noticed.
I figured the only way that could have happened was if a log got caught between the prop and the cavitation plate.
The last time I had it out with my brother we were cruising pretty slow probably about 5 mpg on the Missouri river and we both heard a "thump" from the rear.
It definitely must have been when it happened however I didn't see any logs in the vicinity of the boat at the time.
Well today while planning my attack of straightening the bent cavitation plate, I decided to check the prop and prop shaft. I can visually see that the prop shaft is off center by looking at the threaded prop nut and spinning the prop by hand.
The bearings feel ok. If I stop the shaft on the "high" spot that seems the most off center,...and check the prop blade opposite of it I can tell I have a blade bent back about a half inch.
So now I know for sure something got caught in there.
The shaft looks like it almost has about an 1/8" runout on the very end. Nothing is rubbing anywhere though.
I realize that running a bent prop shaft can cause vibration, which I have noticed, and early seal and bearing failure.
I am fully capable of replacing the shaft but I am wondering if I do so will I have to do any re-shimming of the drive gears in the back?
Also, there isn't much boating season left here in Omaha, NE and I was wondering if it might be OK to run it until winterization. Then pull the lower unit and do it over the winter season.
Here is a couple pictures.
Thanks for any input.
Chris.
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