My Wheel steering on the Catalina 30 tends to shake especially at the higher RPM setting while motoring. At 1500 there is relatively no shake or viberation of the wheel. At 2000 to 2500 there is a modest shake and a turning tendency, and I am assuming that it is coming from turbulance off the the prop. I recently adjusted - tightened my steering and there seems to be no help. While under sail the wheel is very steady. Just wondering if the rest of you Catalina 30 owners experienced the same tendency. Also, was wondering if the Catalina 34 had the same feeling.
- Status
Prop Trubulance
That is normal for the rudder to shake when the boat is motoring. Nothing wrong there.
That is normal for the rudder to shake when the boat is motoring. Nothing wrong there.
John, it would help if you shared the year and
engine you have in your boat. We have an M25, 3 cylinder, 21 HP Universal. Couple of things to check, in addition to the prop: coupling bolts (some of mine have fallen out over time - you need fine thread replacement bolts and Locktite, I haven't found room behind to make a lock washer fit - result of a "thrown" bolt is a very unsettling rumble as you describe); engine mounts - are the four of them in tight at the base? - sometimes the lag bolt back out. What you describe as the wheel pulling is the result of prop walk, which happens in BOTH directions. Just keep the wheel turned slightly to starboard to go straight when motoring. Let's start here and see where it takes you.
engine you have in your boat. We have an M25, 3 cylinder, 21 HP Universal. Couple of things to check, in addition to the prop: coupling bolts (some of mine have fallen out over time - you need fine thread replacement bolts and Locktite, I haven't found room behind to make a lock washer fit - result of a "thrown" bolt is a very unsettling rumble as you describe); engine mounts - are the four of them in tight at the base? - sometimes the lag bolt back out. What you describe as the wheel pulling is the result of prop walk, which happens in BOTH directions. Just keep the wheel turned slightly to starboard to go straight when motoring. Let's start here and see where it takes you.
Engine/Shaft Coupling Alignment, Cutlass Bearing
John, I have a Universal M-18 two cylinder engine with two blade prop in my 1988 Mark II model and have gone through the same problem last year. In fact their was a good thread running on the engine alignment process. Many things can cause the cavitation at varying rpms your experiencing. A damaged prop, worn cutlass bearing, mis-alignment of the engine and the prop shaft, engine mounts loose, sloppy rudder post, etc, etc. I do not know the age or engine type you have nor when the cutlass bearing was inspected when last out of the water. The cutlass bearing being rubber will wear over time and allow the shaft to wobble. If you do a search on engine alignment you will note that the proper alignment between the engine and shaft is determined by the measured in the engine/shaft coupling. That gap between those bolts (4 or 5) that hold the coupler together is where the measurement is made all around the unit to determine if the engine is slightly off alignment. Adjustments are made by through engine mount bolt adjustment. If your abit sensitive about trying this, your not alone!! If you tried to re-tighten and loosen engine mount bolts you can cause more problems then you already had if you did not know what your doing! Take it from me!! Its best to bring in an expert to check the alignment and make the adjustment for you. Its not a lengthy process. Once the proper alignment has been established and the cavitation still occurs, its highly likely its aft of the engine/shaft coupler and in the shaft, cutlass bearing, prop or sloppy rudder. You would not know anything until the boat was hauled and everything inspected after the engine alignment was done. Bob
John, I have a Universal M-18 two cylinder engine with two blade prop in my 1988 Mark II model and have gone through the same problem last year. In fact their was a good thread running on the engine alignment process. Many things can cause the cavitation at varying rpms your experiencing. A damaged prop, worn cutlass bearing, mis-alignment of the engine and the prop shaft, engine mounts loose, sloppy rudder post, etc, etc. I do not know the age or engine type you have nor when the cutlass bearing was inspected when last out of the water. The cutlass bearing being rubber will wear over time and allow the shaft to wobble. If you do a search on engine alignment you will note that the proper alignment between the engine and shaft is determined by the measured in the engine/shaft coupling. That gap between those bolts (4 or 5) that hold the coupler together is where the measurement is made all around the unit to determine if the engine is slightly off alignment. Adjustments are made by through engine mount bolt adjustment. If your abit sensitive about trying this, your not alone!! If you tried to re-tighten and loosen engine mount bolts you can cause more problems then you already had if you did not know what your doing! Take it from me!! Its best to bring in an expert to check the alignment and make the adjustment for you. Its not a lengthy process. Once the proper alignment has been established and the cavitation still occurs, its highly likely its aft of the engine/shaft coupler and in the shaft, cutlass bearing, prop or sloppy rudder. You would not know anything until the boat was hauled and everything inspected after the engine alignment was done. Bob
Engine Type
All good information. I have an 89 Catalina 30 with a Universal 25. I have the bottom, prop and shaft cleaned every 60 days. I had the Cutless bearing replaced the last time it was hauled. I have yet to check, but will take a look at the engine mounts and shaft coupling. Seems some thing the shimi is normal given the proximity of the prop to the rudder.
All good information. I have an 89 Catalina 30 with a Universal 25. I have the bottom, prop and shaft cleaned every 60 days. I had the Cutless bearing replaced the last time it was hauled. I have yet to check, but will take a look at the engine mounts and shaft coupling. Seems some thing the shimi is normal given the proximity of the prop to the rudder.
- Status