lewmar 140 tt thruster shear pins

[grahamdouglass]

Has any one replaced the shear pins on the 140 or 185 Lewmar bowthrusters?
I went to test my thrusters for the first time since last fall and it sounds like I broke my shear pins. There was a wierd high pitched sound then just the motor running with no movement on both port and starboard thrust.

On the Vetus the shear pins are replaced while in the water by lifting the motor off of the drive assembly. On the Lewmar the maintenance manual is not that clear.

 

[PMF1984]

Same as a Vetus, but the Vetus is easier to change out the pin once you get the unit off.

See and download the Lewar manual at: https://www.lewmar.com/sites/default/files/110TT-300TT Gen 2 Issue 4.pdf

I had to use PB Blaster and heat to get the bolts out. Heat was applied by a heat gun, no open flame allowed

 

[grahamdouglass]

Shear pins fine on bow thruster

So I picked up some shear pins and lifted the motor. The shear pin was fine.
$20 and an hour and a half of my time did not do the trick.

The motor turns on both port and starboard. There is absolutely no thrust action. When it broke, it happened quickly. I gave the thruster a quick test, the first time since last September. There was a what sounded like a "loud thruster sound", not that unusual, and then only for a second before the thruster mottor had a racing sound of a motor with no load on it.

Is there an other shear pin located in the propellor housing or is it something really serious like a damaged V drive gear assembly.

Any thoughts out there in trawler forum land before I pay the big bucks to have the boat hauled and get the boat dollar meter churning?

 

[PMF1984]

Graham,

The trouble section of the Lewmar manual implies its either a broken shear pin or broken prop blades.

can you have someone dive on the unit to inspect the lower end? ...But sounds like a haul-out either way. Change the zincs while you are at it.

John