I hired Your Boat Shop to replace the engine mounts on my motor vessel. What should have been a routine maintenance item ultimately resulted in a catastrophic port transmission failure and more than $25,000 in repairs. Prior to the engine mount replacement, a pre-purchase survey documented no shaft binding, drivetrain abnormalities, or transmission concerns. After the work was completed, the vessel was operated for several months before the port transmission failed while underway in May 2025. Following the failure, Harbor Marine, a ZF-authorized service facility, inspected the drivetrain and documented a constant 0.010" coupling misalignment through a full 360-degree rotation. Harbor Marine also found the port shaft seized in the cutlass bearing, replaced the cutlass bearing, realigned the strut, replaced the transmission, and performed a complete drivetrain realignment. The transmission was determined to be damaged beyond repair. Independent documentation of the repairs and findings was provided by Harbor Marine. An independent SAMS-accredited marine surveyor subsequently inspected the failed transmission and documented extensive internal damage, including fragmented intermediate shaft roller bearings, metallic debris contamination, gear damage, and a seized cutlass bearing. The surveyor reported that the transmission-to-shaft coupling was grossly out of alignment and concluded that the failure sequence was precipitated by shaft misalignment following the engine mount replacement. The survey also noted that proper alignment had not been achieved after the mounts were replaced. What concerns me most is that this does not appear to have been an isolated alignment issue. During the investigation of my claim, I reviewed documentation from CSR Marine involving another vessel serviced by the same shop. CSR Marine found engine alignment measurements of 0.016" on the port side and 0.023" on the starboard side, despite an accepted standard of 0.003" or less. CSR concluded that the shafts appeared to have been reinstalled without properly aligning the engines and recommended substantial corrective work, including disassembly, replacement of worn cutless bearings, and complete realignment. Equally disappointing was Your Boat Shop's response after the failure. The shop was notified immediately and was given the opportunity to participate in determining the cause of the transmission failure, but declined to become involved in the investigation. As a result, the burden of diagnosing the failure fell entirely on me. Although my insurance carrier could not provide coverage because the underlying work predated my policy, they did reimburse towing, haul-out, and discovery-related expenses and retained independent experts to document and evaluate the damage. The root cause investigation proceeded without any meaningful participation from Your Boat Shop. Mechanical failures can happen. What matters is the quality of the work performed and how a company responds when serious problems arise. In my case, a routine engine mount replacement was followed by documented drivetrain misalignment, a seized cutlass bearing, catastrophic transmission damage, extensive repairs, and a lengthy investigation that the shop chose not to participate in. Based on my experience, the findings of Harbor Marine, the conclusions of an independent SAMS-accredited marine surveyor, and the separate alignment findings documented by CSR Marine on another vessel, I have no confidence in the workmanship, quality control, or accountability demonstrated by Your Boat Shop or Chris Tomlinson Marine Services. There are many marine service providers in the Pacific Northwest. After this experience, I would not trust Your Boat Shop or Chris Tomlinson Marine Services with any work on my vessel.