The Taming of the Boat Trailer.
By Larry Nielsen

Last summer my spouse and I bought a used sailboat. It met the criteria that we had set for it. It had to be a beautiful boat that would sail well, be up to navigating the waters of the Apostle Islands with care, allow us some sleeping space, be affordable, and would be able to be moved by a trailer.


We looked carefully at the boat and had it assessed. We knew that an S-2 was well built and this 22 footer, in addition, was well maintained. It was a fairly affordable boat costing only twice what we had planned to pay. However, it is well known all sailors are delusional when it comes to cost.


We did not pay a lot of attention to the trailer. I did notice that its tires were not fully inflated and that there was evidence of a little rust on it here and there. The boat was what counted and, besides, the marina only moved the boat and trailer about 100 yards every spring and fall. It was sort of a cradle on wheels.


Then came the day when we decided we were going to take the wonderful boat and questionable trailer down the highway. I looked at the tires, now fully inflated, and found cracks in between the treads, on the side wall, and around the bulges where the boat had sat for at least a year while waiting to be sold. It survived the trip home from Duluth to our home near Minneapolis, MN so that my mechanic son, Ben, could look at it with me.


Ben looked at the tires and said, "They are toast, Dad, you need new ones. By the way you do not have a spare and you will need one. While we are at it we need to look those brakes and how are the bearings and lights?" Good son.


It was then that I began to think of all the dead boat trailers I had seen along our highways. Ones with blown tires, burned out bearings, motors bouncing up and down, or things flapping in the wind. I remembered the boat trailer with a broken spring that had passed me at more than 70 miles per hour on the interstate. It had received a temporary repair by lashing some firewood between the frame and axle. Then there was the boat, trailer and very small SUV lying in the median of an expressway. The large motor was still attached to the transom that was joined to the boat only by one of the gunwales, and was swinging in the breeze. The straps still held to boat to the trailer and the trailer still on the hitch. The owner sat at the edge of the road checking to see if all his body parts were there. The whole thing had flipped end over end.


So what do you do with your trailer? First, if you are not a good mechanic, find one who will spend a little time with you. One that will tell you that you do need the brakes because you will not be able to make a quick stop without them. The guys at a Tires Plus store were really helpful. There are many other tire and brake places that will give you a lot of assistance, that is their business.


They looked at my tires, asked how much the boat weighed and what kind of driving I was going to do with the unit. This will determine the "load range." They looked at the old tires and found that they were on an old system of classification, and had conversion tables that take care of that. The tires that were on the trailer were a load range of "C" and they recommended going up a grade to a load range of "D" which would handle another 500 pounds per tire. You will find the weight limit and air pressure for your tires printed on the sidewall of the tire-this is weight limit per tire.


Trailer tires are different than truck or automobile tires, they are designed to be towed. The rim we got for the spare was identical to the original and that was a surprise after 14 years! Ben suggested that I use radial tires as I had a single axle trailer. Bias ply tires are often preferred on multiple axle trailers as they have more side flex and will more easily allow a sharper turn. It was also suggested to block up the axles in the fall so that the tires would not bear the weight of the boat and trailer all winter. Protecting trailer tires from sun light is also a good idea. "Remember, Dad, keep these inflated to the 60 pounds they are supposed to have, check them every time," Ben reminded me.


Trailer brakes come in drums and discs, just as they do on cars. Two different mechanisms are used on either type to get them to apply when you stop. Mine were a type called "surge brakes" which are actuated by the trailer and load pushing against the towing vehicle and its hitch when its brakes are applied. There are also electric brakes that are engaged by a unit in the towing vehicle that reads the brake light circuit and applies the brakes electrically.
We looked at the brakes. Upon opening the brake fluid reservoir on the hitch, we found a combination of brake fluid, water, chunks of rubber and some strangely colored substance floating on top. The whole assembly was rusty with the breakaway lever firmly welded in place by rust. The brake lines were covered in rust and the wheel cylinders were frozen in place. The trailer had not had brakes for at least 12 of its 14 years of life! It was then that we concluded that the trailer had been in seawater at some time.


The brakes were a major concern to me. The average automotive parts store does not have a ready access to trailer parts. I found several places that sold trailer parts that were quite good. For the average consumer either Northern Tool and Equipment Company (formerly Northern Hydraulic) or Fleet Farm had a lot of things you might need. Northern had the master units for the surge brakes and electric brakes. They also sell many brake wheel units. You will find that individual parts such as a wheel cylinders or brake shoes are not readily available. The whole unit with backing plate and all the parts that will bolt onto the end of the axle very quickly and are your best bet. There is not a lot of variation among trailer hardware.


The problem I had was that the brakes on my trailer were heavier duty than most and the parts were now hard to find. If you encounter this, tell your marina, tire store or mechanic to try Pioneer Rim and Wheel who have warehouses not open to the general public in Minneapolis, MN, Madison, WI, and Fargo, ND. My son as a mechanic has an account with them, which gave me the chance to see their Minneapolis operation. We brought the parts to them and found to our delight that everything we needed was easily recognized by the staff, was in stock and was original manufacturers' equipment!


The parts assembled beautifully as they were exactly what we needed. We replaced everything, the hitch and master brake unit (all one piece), the lines, and the brake assembly at the axle ends. The original brake drums were able to be turned at a local brake and tire shop. The old brake lines were rusted through from the inside and broke in two places as we removed them. The instructions with the surge brake-a Titan (used to be DICO) model 60-were easy to follow and worked well. The braking is a success when are towing and you apply brakes on your towing vehicle and it feels normal. Ben said, "Check the brake fluid every time you use the trailer, Dad."


A note about backing up with trailer brakes. The electric ones can be turned on and off from the drivers seat and are no problem. If a standard brake assembly is used with a surge brake it is necessary to disarm the brake-usually with a pin-before backing. Most manufacturers sell a trailer brake that releases in reverse, even when the master unit is calling for braking. In either case, trailer brakes do not work well or at all in reverse.


While we were working on the brakes we inspected the bearings and replaced them-a very cheap insurance. The new bearings got new seals and marine grade grease-a good idea if you plan to immerse the trailer wheel. The packing with grease took about ˝ the 16 ounce can per side. We ended by filling the bearing cup with grease. We were not able to find a product like "Bearing Buddies" in the size we needed, however, they are a great idea. They allow adding grease with a gun and keep positive pressure in the bearing chamber. "Remember Dad, do not mix different kinds of grease! It is a good idea to change the grease about every other year."


The trailer lights were in need of replacement. There are a lot of various kits around for these and the best thing is to shop for them. Do not scrimp on connectors! It is often here that the water and road dirt will end the life of your electrical system at an early age. Be sure that you provide a ground return (the white wire) from trailer to towing vehicle. Many trailer light failures are caused by a poor ground.


If you are concerned about rust on the trailer frame, an old trick is to take a hammer and tap lightly. You should hear a ring. If you hear a thud it is heavily rusted then replace the trailer.


One last thing, take an adjustable wrench and screwdriver and walk around your trailer and give everything a twist. Before I moved the trailer the first time, I discovered that two of the six wheel nuts on each wheel of my trailer were only finger tight. It only takes a minute and gets rid of a rattle or two.
Like anything else, good maintenance before you leave home is the best insurance for a happy trip. Good sailing!

Larry Nielsen and his spouse, Mary Ellen have sailed for 15 years on Lake Superior in boats of many sizes and kinds. They have owned and sailed smaller craft such as a Chrysler Buccaneer, on inland lakes. Prior to this Larry lead more than 40 canoe trips in the Boundary Waters Canoe Area. Other boating for Larry includes powerboats, inboards and outboards on lakes around Detroit Lakes, Bemidji, Mille Lacs, and others. Larry and Mary Ellen are the proud owners of the Divino Blü, a 22 foot S-2, berthed at Barker’s Island in Superior. Ben Nielsen, Larry’s son, is a mechanic who prefers his 1972 Dart with a 340 cubic engine to boats.