Posted by Dave on Oct 23rd 2023
Trouble shooting chain and cable sailboat steering
As harbors begin to thin out with the cooler seasons coming in, it’s a great time to evaluate whether your boat’s steering system lived up to its potential or if there are some things that could be improved. This article will help you identify the root causes of most steering irregularities and fix them. Many require only adjustment of existing parts. These tips are relevant to any chain and cable steering system, whether by Edson or another brand.
Slop or in the steering wheel: Slop or lag is most often caused by insufficient cable tension. Without enough cable tension, the rudder is able to move through a few degrees without any steering input, and the cable will need to “catch up” to steering inputs from the wheel. To determine if your sloppy steering is caused by insufficient cable tension, have someone turn the wheel hard over while you observe the cables. If the slack cable visibly sags when the wheel is hard over, more tension is needed. Add tension symmetrically to each tension adjuster in small increments until the slack cable no longer droops, and then add ½ turn of tension to each tensioner. More tension that that can cause friction and premature bearing wear. Be sure to reinstall the second set of nuts to ensure the system stays put where you adjusted it.
If the cables are adequately tensioned and there’s still slop or lag, the next place to check is the wheel’s fit to the steerer. Apply firm tension to the wheel brake, and try to turn the wheel back and forth. If there’s movement at the wheel, apply some tension to the wheel nut. If there’s still play in the wheel, it’s likely that the steerer shaft key is worn and should be replaced.
The wheel moves fore and aft: Your steering wheel should essentially not move fore and aft. If there is any appreciable movement along the direction of the steerer shaft, this needs to be addressed as this can cause some bigger problems.
The almost certain culprit here is a broken snap ring, which is cheap and easy to replace. The steering system relies on snap rings to hold the steerer shaft in place fore and aft. Without functioning snap rings, the chain won’t be held in its proper alignment, causing wear on several moving parts and risking bigger problems. This is an easy and important one to fix before next season.
Excessive friction in the steering system: A sticky steering system can have many causes, from autopilot seal friction to worn rudder bearings to several potential causes within the steering system. The first step in troubleshooting system friction is to disconnect the steering cables from the quadrant, and remove the autopilot ram from the autopilot tiller arm. This isolates the major variables within the system.
With the steering cables and autopilot disconnected, turn the rudder back and forth by hand. A spade rudder on a race boat should turn easily with no appreciable friction, while a cruiser’s skeg-hung rudder will have a bit more resistance, but should move smoothly with no pronounced bumps or hard spots in the steering arc. If the wheel offers significant resistance in this test, one or more of the bearing surfaces is misaligned or damaged. Correcting that should provide a big improvement.
If the rudder turns smoothly without undue force, reconnect the autopilot ram to the autopilot tiller. Older autopilots can add significant resistance thanks to hydraulic seal drag, which doesn’t have an easy solution. Autopilot manufacturers have significantly decreased this seal drag in recent years, to the point where the pilot may not add any appreciable drag to the steering system.
Next, go up on deck and gently turn the wheel hard over to hard over. There may be some cable- or chain-slapping because the cables are loose, but the wheel should turn freely through its whole arc without any binding or grinding. If you feel roughness or play in turning the wheel, it’s likely that the needle bearings that the shaft rides on are worn out. Needle bearings typically have a 20 year service life if properly maintained, although hard use and a lack of regular greasing (using only Teflon-based grease) can dramatically shorten service life. Replacing needle bearings is relatively easy. If the plastic cage on a needle bearing breaks, the wheel can become jammed and cause you to lose control of the boat. Regularly grease the bearings and replace them at regular intervals and you should never have a problem.
Watch the chain roll over the sprocket as you turn the wheel. It should be smooth, without any jumping on the sprocket teeth or binding. A stiff link indicates an improperly lubricated chain, which means the chain is a good candidate for replacement.
Finally, check each sheave in the system. If you find bronze sheave pins anywhere, replace them. Bronze pins haven’t been regularly used in about 30 years, and if they are still in your boat they are now well past their service life and are likely dangerously worn. Stainless replacements are available and are much more durable. Check the sheave cheeks for wear, likely caused by either insufficient cable tension or cable misalignment. The cotter pins on the sheave pins should be held in place by nubs on the uprights, which prevent the sheave pins from turning. Sheave pins should be regularly lubed with a medium weight oil – 3-in-1 oil is great for this.
Steering should be the best part of owning a boat. Don’t let a bit of misalignment or improper adjustment stand in the way of enjoying your boat.