311 SR1 TRS Failure
#1
311 SR1 TRS Failure
Had a pretty big failure - threw a driveshaft on one of the engines/drives (420/TRS). I wasn't on the boat at the time but I think operator may have mistakenly trimmed up into trailer mode and tried to plane out. They reported hearing a loud sound the the engine stalled. Came back and found water leaking in from a cracked inner transom plate. U-joint separated. Engine took on water and hydro locked but I was able to free it up and compression is good. Will need to replace driveshaft and inner plate at a minimum. Stock 420 w/ TRS never abused, hardly run over 4200RPM w 28P 3 blades. Surprised as TRS drive is solid when left stock, guessing had to be operator error?
Might as well do gimbal while in there - any other suggestions/comments?
Thx
Might as well do gimbal while in there - any other suggestions/comments?
Thx
#2
Registered
There is no gimbal bearing on a TRS, they have two sealed bearings inside the tail stock of the transmission. You will likely have to pull transmission and tailstock to replace those.
#3
That makes this make more sense to me. This is my first experience with TRS drive work, and I was having a hard time seeing how the hell the inner transom plate got cracked. The tail shaft of the velvet drive is about an inch or so long right? So there must be another shaft that connects the transmission to the outdrive input shaft with the U-Joint on it correct? If that does even exist, could it have broken apart and cracked the inner transom plate? Trying to find some diagrams or photos online, but I might just start pulling it apart and figure it out.
#4
Registered
lol "velvet drive" - sounds like the name of actor in a bad 80s adult film.
#6
How did the engine get water in it? Separate issue?
Did the drive seize up causing this or is it ok?
I had water come in throuh a ripped bellows. The input shaft rusted to the tailstock bearing allowing no shaft movement. This took out the ujoints which destroyed the transom assembly
Did the drive seize up causing this or is it ok?
I had water come in throuh a ripped bellows. The input shaft rusted to the tailstock bearing allowing no shaft movement. This took out the ujoints which destroyed the transom assembly
#7
How did the engine get water in it? Separate issue?
Did the drive seize up causing this or is it ok?
I had water come in throuh a ripped bellows. The input shaft rusted to the tailstock bearing allowing no shaft movement. This took out the ujoints which destroyed the transom assembly
Did the drive seize up causing this or is it ok?
I had water come in throuh a ripped bellows. The input shaft rusted to the tailstock bearing allowing no shaft movement. This took out the ujoints which destroyed the transom assembly
Drive itself seems OK aside from driveshaft.
I think the water intrusion is from the engine being stalled from 4000RPM at probably 30-35MPH, I'm guessing it came up the exhaust. Engine runs fine now and compression on all cylinders is good so hopefully it didn't hydrolock, but got water in after it turned off and just couldn't be cranked afterwards.
Ugh. This ones gonna be BOAT dollars.
Last edited by 311SR1; 10-05-2020 at 12:45 PM.
#8
Registered
I guess this is where trim limit switches come in handy.
#9
Do the trim limit switches do anything when you press the “trailer out” switch? Because that’s what she hit. The limit switches work when you press the trim up buttons, stops the drives from coming up any higher than they should, way lower than trailer mode while will raise them almost to the point the prop is out the water.
The boats on a slip. I’m probably going to disconnect the trailer out switch just so it doesn’t happen again. I’m the only one who puts it in the trailer anyway.
I wish there was something to alert or not allow power to be applied if the drives are raised past the trim limits.
The boats on a slip. I’m probably going to disconnect the trailer out switch just so it doesn’t happen again. I’m the only one who puts it in the trailer anyway.
I wish there was something to alert or not allow power to be applied if the drives are raised past the trim limits.