I am stuck with this project and looking for advice.
1983 Formula Thunderbird 23ft with the Mercruiser 260 and PRE-Alpha One drive. It is the one with fins on the top sides and a lifting hook on the top cap.
The back story is a few years ago I was at Jackson lake with the family, the 9 year old fell of the tube, and in my haste to go back for him I pulled a hard left turn. After that the boat lost forward and reverse. I turned the engine off, jumped in the water and checked to see if maybe it spun the prop hub. I had someone put the lever in forward, then reverse and both ways the prop just spun.
I did some research and expected a coupling and parked the boat, since the prop shaft turned with the prop.
Fast forward to this weekend. I pulled the drive after putting it in forward, hung the drive from my lift and drained the oil.
Here is the cliff notes of where I am at.
The shift cable feels firm at the throttle lever and moves back and forth on the bracket behind the motor.
Pulled the prop, pulled the drive, and hung it from my lift to drain the oil.
Oil that came out was dark, but no water or metal.
I pulled the top cap before I drained it, it had oil up top. Gears looked fine.
The shift rod moves, in one direction I can turn the prop one way, but it feels like a racheting is going on when I spin the other way.
Move the shift rod the other way and the prop rachets the other direction but is firm the other way. If I grab the prop and turn it the input shaft and CV joint turns. This works both ways.
I looked through the gimbal with a flashlight at the coupler. It's intact, rubber is solid and there wasn't any rubber dust around the back of the motor.
When it happened at the lake I don't remember if it got hot or not. It was the first time I have had an issue on the water,
So at this point I have a few questions.
I do plan on pulling the lower and replacing the impeller since I am this far into it, but am not sure where to go next to make sure it's all good. I don't have a lake close by to drag it to for a test run just to find out it has other problems.
I do have muffs, but I want to drain the fuel and possibly rebuild the carb before I fire it back up.
How do I make sure the lower shift linkage is working?
Is it possible the shift cable appears to work fine but doesn't, and can that problem suddenly happen or is it gradual?
Should I replace the impeller, put the drive back on, put new fuel in it and start it with the muffs on and see what happens?
I do have another stainless prop I could put on even though the hub looks ok.
One of the things I am confused by is how the shift mechanism works in the drive. Not internally, but the part on the end of the cable that comes through the gimbal.
The lower has a rod that turns at the top for forward, neutral and reverse, but it doesn't make sense how the metal part on the end of the cable moves it.
What should I do next?
1983 Formula Thunderbird 23ft with the Mercruiser 260 and PRE-Alpha One drive. It is the one with fins on the top sides and a lifting hook on the top cap.
The back story is a few years ago I was at Jackson lake with the family, the 9 year old fell of the tube, and in my haste to go back for him I pulled a hard left turn. After that the boat lost forward and reverse. I turned the engine off, jumped in the water and checked to see if maybe it spun the prop hub. I had someone put the lever in forward, then reverse and both ways the prop just spun.
I did some research and expected a coupling and parked the boat, since the prop shaft turned with the prop.
Fast forward to this weekend. I pulled the drive after putting it in forward, hung the drive from my lift and drained the oil.
Here is the cliff notes of where I am at.
The shift cable feels firm at the throttle lever and moves back and forth on the bracket behind the motor.
Pulled the prop, pulled the drive, and hung it from my lift to drain the oil.
Oil that came out was dark, but no water or metal.
I pulled the top cap before I drained it, it had oil up top. Gears looked fine.
The shift rod moves, in one direction I can turn the prop one way, but it feels like a racheting is going on when I spin the other way.
Move the shift rod the other way and the prop rachets the other direction but is firm the other way. If I grab the prop and turn it the input shaft and CV joint turns. This works both ways.
I looked through the gimbal with a flashlight at the coupler. It's intact, rubber is solid and there wasn't any rubber dust around the back of the motor.
When it happened at the lake I don't remember if it got hot or not. It was the first time I have had an issue on the water,
So at this point I have a few questions.
I do plan on pulling the lower and replacing the impeller since I am this far into it, but am not sure where to go next to make sure it's all good. I don't have a lake close by to drag it to for a test run just to find out it has other problems.
I do have muffs, but I want to drain the fuel and possibly rebuild the carb before I fire it back up.
How do I make sure the lower shift linkage is working?
Is it possible the shift cable appears to work fine but doesn't, and can that problem suddenly happen or is it gradual?
Should I replace the impeller, put the drive back on, put new fuel in it and start it with the muffs on and see what happens?
I do have another stainless prop I could put on even though the hub looks ok.
One of the things I am confused by is how the shift mechanism works in the drive. Not internally, but the part on the end of the cable that comes through the gimbal.
The lower has a rod that turns at the top for forward, neutral and reverse, but it doesn't make sense how the metal part on the end of the cable moves it.
What should I do next?
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