V-Drive damage – manufacturing defect




August 2nd 2011
RE: Insured: Mr. xxxxx
Claim #: Removed for Privacy
Date of loss: July 4th 2011
Vessel: 1987 Removed for Privacy Sportfisher
Our file #: 11-12133

Dear Mr. xxxxx:

Thank you for the above captioned assignment, received on July 11th 2011.

V-drive Inspection

We were contacted by the insured on Friday, July 29th 2011. He stated that the V-drive had been delivered to rmp’s Marine and partially disassembled. We spoke with Mr. Removed for Privacy of Removed for Privacy’s Marine Engines. He stated that the V-drive had been disassembled to a point that would allow a determination of the cause of loss.

Mr. Removed for Privacy stated that he wanted to attend the inspection of the machinery. Mr. Removed for Privacy is an engineer and he wanted to see how the V-drive functioned and why it failed. We met with Mr. Removed for Privacy at Removed for Privacy’s Marine Engines on August 1st 2011. The V-drive and transmission were partially disassembled.

The failure was the loosening of the keeper nut on the output shaft for the V-drive. The keeper nut is designed to be held in place with a tab bent over on a locking washer. The tabs on the lock washer appear homogenous, and none indicate any damage or visible difference.

Mr. Removed for Privacy stated that the V-drive unit appears original, with no indication of significant work. Mr. Removed for Privacy stated that the top cover has likely been removed for cleaning but the rear gasket appears original. Mr. Removed for Privacy stated that Walter, the manufacturer of the Vdrive, only sells parts when provided with a serial number. Walter has no record of ever selling parts for this V-drive.

Mr. Removed for Privacy stated that the lock washer comes into play when the transmission is shifted into reverse, as this is the direction that would pressure the nut to loosen. The nut is kept in place when the transmission is engaged in forward.

Cause of Loss

Based on all of the details available, it is our opinion that the lock washer tab was never bent over and engaged in the nut serving to retain the output shaft in the V-drive assembly. The cause of loss was a manufacturing defect. The nut gradually loosened and eventually came off the shaft, allowing the shaft to become dislodged from the Vdrive when the insured engaged the transmission in reverse. Conversely the bent tab on the washer became unbent, returned to an angle of all the other tabs and did so without exhibiting any sign it had ever been bent, this is highly unlikely.

V-drive Repair Estimate

Mr. Removed for Privacy provided a copy of the repair estimate to the insured. A photograph of the estimate is attached. The repair estimate is claim related, fair and reasonable. The repair estimate from rmp’s supplements the repair estimate from Sunset Aquatic Shipyard.


1. Photographs (including repair estimate)

Thank you for the opportunity to be of service. Please contact the undersigned with any questions or if there is anything further we can do to further assist with this claim.


Kells Christian
Christian and Company
Marine Surveyors, Inc.