Sturdy Throttle Controller Issues

Throttle Controller Issues - having problems getting the engines to exceed 1,500 RPMs with Sturdy controls on 2002 50 ft Hatteras sportfisher, CAT 3412e engtines. Sturdy corporate and independent mechanics have been unable to solve the problem. The engines have been thoroughly serviced and in great condition. From what I understand, this is not a new issue for Hatteras owners. We're now considering replacing with Glendinning controls. Anyone have experience in this area? Appreciate the feedback!

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