Hi all, I intended asking Catalina 28 owners what speed I should get under power with a Yanmar 3ym 20 but read old posts about the 28ts pulling to port. Mine has a bad pull to port under power. I recently completed an 800mile delivery trip in it and with light winds had to motor sail for long periods. The pull to port made the trip very tiring, especially on overcast days with no visible landmarks and worse at night, it meant 100% concentration compass and gps or in a few seconds she would veer off course 20 to 30 degrees. This lead me to believe that I had a bent rudder shaft or alignment problem. When I slipped the yacht I discovered that the rudder shaft appeared to be straight but when sighting along the face of the rudder on each side to the centre of the keel the rudder appears to offline to port by at least 20mm. With several other owners reporting the same problem, but no one seemed to have a solution, and these posts were 8 years old I was wondering if a way to correct the alignment has been found. I have owned many boats, yachts and cruisers, and never had this problem before, there must be a solution. Any help would be much appreciated. With the 3ym 20 yanmar my top cruising speed at 2800 is 5.2knts, is this normal?
Catalina 28 Cruising speed under motor Hard pull to port
- Thread starter William Weeks
- Start date
Have you contacted Catalina Yachts for their input? It it's an ongoing issue then they would have most likely been made aware and may have a fix already in place. Worth a try in my opinion. Their parts and tech support number at the factory in Florida is 727-544-6681 See the bottom of the opening page of their website.. www.catalinayachts.com
Prop walk = a pull to port is a normal consequence of the way our propulsion systems are aligned.
I have used two solutions while motor sailing:
1. Rig a shock cord to the tiller to balance the prop walk. Varying the tension of the shock cord adjusts its force on the tiller.
2. Then I bought a tiller pilot. It's a complete solution while motoring, and does not run down the battery because the engine and alternator are running.
I have used two solutions while motor sailing:
1. Rig a shock cord to the tiller to balance the prop walk. Varying the tension of the shock cord adjusts its force on the tiller.
2. Then I bought a tiller pilot. It's a complete solution while motoring, and does not run down the battery because the engine and alternator are running.
Hi Joe, thanks for your input, yes I contacted Catalina about the problem and they wouldn't admit that there was an issue, they sent me detailed plans of the rudder construction so I could determine the canter of the shaft but I have come to the conclusion that it's an alignment problem. I had the yacht out for antifouling recently and ran string lines down each side of the keel and all I could find was the top of the rudder shaft was about 15mm. off center to port. But it's very obvious that the rudder doesn't line up equally with the keel on ede siach s
Sorry about the previous message, had a computer glitch, was supposed to read line up equally on each side. Regarding the prop walk comment, as I mentioned previously, I have sailed many yachts and never encountered this extreme amount of port helm, If I let the wheel go the boat immediately goes hard to port, but in a large following sea the affect overpowers the wheel pilot and she rounds up to port. I know that Binks 30s and other yachts with offset props encounter this helm when under power, the Catalina 28 has an in-line shaft so I think it's more an alignment matter. I was hoping someone has come up with solution because it appears that a lot or 28s have this problem. It is a shame that this happens as under sail she balances nicely
I can't imagine there is a simple solution to the rudder shaft alignment. It seems you will just have to live with it. Do you not have a wheel pilot? Is the pull strong enough to override a wheel pilot? If it is only an issue when motoring, I would rely on the wheel pilot as long as it can do the job for you.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 23,009
If the pull to port dissipates when you are coasting then the pull to port could be induced by the prop. You might consider changing the prop pitch, or getting a more efficient prop design.
I had a prop that caused strong pull to port and pulled the stern end of the boat down as much as 0.4 meters when running at near WOT.
I changed to a much improved design, the Campbell Sailor. I got more efficient thrust. Less prop wash pull and no more sinking stern.
It might be an area to explore on your boat.
William, as some one stated it is a prop walk issue, however your description sounds excessive. If the pressure stops when throttled down and put in neutral this confirms it. Many thoughts for you. I have had a C-28 for over 20 years and understand the issues, you also probably have the walk to port in reverse, both are not uncommon in sailboats in general but like I said yours sounds excessive. I would ask what prop you have and how many blades. Your 2800 rpm at 5.2 knots throws up a red flag to me. Perhaps some one has re propped and it made it worse, not wanting to throw a lot of money at it probably sold the boat. To me it sounds like a re-prop will make it better but to be honest it will never totally go away. I would invite you to the Catalina 28 group on Yahoo, it's been around a long time, is free and we have some great guys and documentation there. Some have re-propped in various configurations and improved things. You can see what people have done and the results they have gotten. You can use the search engine on there to research years of discussion and attempted solutions. Also you state you have a Yanmar, are you sure it is not a Universal? I see also that it is a MKI, what hull number? Catalina also publishes a magazine called Mainsheet it has a section on all of the Catalina models including the 28. I am actually the technical editor for it. Search out the Yahoo group I promise it will be helpful for you as well.
Hi KC, thanks for your thoughts, as I mentioned in earlier posts, the pull to Port when motoring is so pronounced when motor sailing in rough conditions that it is near impossible to steer a straight course. the autopilot will handle most conditions but with 2.5m following swell, the pilot will correct to Stbd ok but when correcting to Port the helm is sometimes overpowered and the boat will round up. This is not the best situation in rough conditions. On one occasion during a 180-mile leg of my delivery trip my auto pilot failed and I had to hand steer for the last 5hrs in the dark, without landmarks or stars due to rainy conditions, and found that I was veering off course in a matter of seconds if I took my eyes off the compass. I appreciate that prop wash can cause port helm, I have owned 3 similar sized yachts, and 5 inboard cruisers and never before encountered a helm like this. I have a 3 blade Feather Stream feathering prop which was sized to suit the yacht and the engine will rev out to 3,600 RPM under full load, full throttle, which should mean that it is the right size. I can make 6knots just, @ 3,000 rpm, but I prefer to motor at 2,500 rpm = 5.2 knots. The engine is a Yanmar 3YM20 with 700 hrs, it replaced the original motor 2 years ago. The 28 sails perfectly and is well balanced under sail, but on a couple of occasions, one when bashing to windward against 25-30 Knts and 2Knts tide and motor sailing to try and make the anchorage before dark, I found that though the pilot was steering better than I could, it was really overworked and eventually failed a few days later. The main drive Pully was broken in 4 places and only held together by the belt. Though I love the 28, I have to consider whether I can continue doing long passages if I can't correct the rudder alignment. With the yacht out of the water, the alignment problem is obvious but how to correct is not, without major surgery to the rudder stock. I still live with the hope that someone will come up with a solution, Regards Bill.
