A Note About Single Axle Trailers

[HideAway]

I was working on HideAway yesterday - trying to get the teak done before the hot weather hits - I noticed my neighbor across the way was hooking up to his empty single axle trailer to go retrieve his Catalina 22.  The wind was in the high 20s gusting well over 30 - shaking HideAway so much on her trailer  it was difficult to walk on deck.

I needed a break anyway so I watched him recover his boat and after it was in his dry slip I walked over to check on his sanity.   He had the car unhitched and had just stepped into the cockpit when the boat suddenly tipped backwards with a thunderous crash and the sound of an out board hitting pavement.  He was unhurt but the Catalina s stern was hard aground and the trailer tongue was over my head.   It took three of us - we are not small - to pull down the the trailer while he reset the concrete block at the end of the trailer.   He said he had placed the block correctly and the boat was in its usual place on the trailer.  Further inspection showed no leaks - no water in the bilge.  I pointed out the bow was maybe three inches back from the chock but he said he never had a problem before.  After we had the boat mostly horizontal the front trailer wheel was still off the ground.   He said he will reconfigure the trailer - move the boat forward to get more tongue weight.   I ll not be complaining about my double axle trailer so much anymore

[skip1930]

That sums up the reasons I moved the single axle back wards on my CP-19 trailer. To provide more tongue weight for better towing and to prevent the hitch from going skyward when skippy goes astern when the boat and trailer is sitting on the hard.

Additionally the factory had assembled the the trailer in this fashion: The hitch. The jack. The vertical holding the vee block and winch. I changed it to: The hitch. The vertical holding the vee block and winch. The jack. This moves the boat forward on the trailer. More tongue weight.

Before I moved the axle I made a simple jack that I drop AFTER the tow vehicle is un hooked BUT before I climb up on the boat.

skip.

Here is the jack.


Here is the new rearward position of the single axle. The black line with the arrow on it is the factory position. To do this one needs to hump the axle around the most rearward 2" x 2" vertical for the hull bunk. Left is fwd. Right is stern. And once your happy with the location, then jack up the trailer, take off the wheel and tire, drill for a 9/16 nut and bolt and pull that angle iron up tight against the trailer channel. That pulls the bow out of the center of the axle.


The new set up for the trailer to move boat foward. 

[Salty19]

I would be HIGHLY cautious to do what you've done Skip.   What is your tongue weight?  The aft jack is a great idea, but moving the axle to solve a problem that the jack fixes looks kind of dangerous to me.  Again, what is your tongue weight??

Hideaway...wowzers, that must have been quite the site.  Hope his boat is OK.  Scary stuff.

[skip1930]

The tongue weight is not enough to depress the back end of my 1997 Ford Expedition. Tows like a dream and one can twirl the jack handle with one arm and not with too much strain. I don't know the tongue weight. You don't really feel the trailer behind the Expedition at 60 mph.

I know the truck, boat and all it's gear, plus trailer on the scale at Sturgeon Bay Metal scrap yard weigh in at 7634 lb with 1/2 tank of gas. There scale is always on, even when they are closed.

skip.

[HideAway]

Tongue weight is critical when towing.  A friend of mine had a Mariner - a small cabin boat - maybe 18 feet long or so - behind his Ford Ranger as  motored down the interstate headed for Sarasota.  We were just past the Misner bridge when the boat went started Zigging while the truck was zagging.  He was just able to stay in control long enough to pull off at a rest stop at the foot of the Sunshine Skyway - it was scary.  We were able to move the trailer winch forward and use it to crank the boat further up the trailer.   Never tow a boat or anything else without your tool kit  - Anyway that did the trick - If that would have happened on the big bridge I don t know if it would have turned out so well.   That Mariner was a great beach boat and we had many adventures in it.   

[Joseph]

It happens... even if the tongue weight is ok (approx. 10% of the Gross weight), the lever momenta in most short single axle trailers can be such as to cause it to tilt when the weight of a heavy person is added aft in the cockpit. My impression is that most trailers are designed with the axle attempting to coincide with the centre of mass of the boat when the boat is empty and that the weight at the tongue is mainly provided then by the forward part of the trailer and the tongue itself. 10% of the total weight in the case of a Suncat (i.e., my boat) on its trailer would be abt. 200 lbs, which makes it possible for a heavy person (plus perhaps an outboard, etc.) to tilt the loaded trailer if positioned well aft in the boat. Worst scenario: in the Suncat if the rudder has not been lifted up, it will take the extra weight against the ground. When in the dry my solution has been to never move aft in the cockpit unless the trailer is attached to the vehicle, but Skip's idea of a simple jack holding up the rear bar of the trailer is an excellent one. 

J.

[HideAway]

Most folks use concrete blocks not realizing that the blocks are not designed for side pressure and will break.   I m not sure if that is what happened to the Catalina.   I like the jack idea much better 

[skip1930]

Every trailer that is light on the hitch will shash~shay behind to tow.
When a lot of weight is on the hitch then load equalizers help out a bit.

Once coming back from a job in Mt. Sterling, Ky. with a six man crew, we had our Chevy crew cab one ton diesel P-up pulling a goose neck 6-horse trailer, over loaded, pulling a ball hitch 20 foot double axle trailer, also over loaded, coming out of Kentucky pulling uphill in Indiana heading for Toledo, Ohio, against the wind on the toll road. We could barley hold 45 mph, the automatic kept dropping into passing gear, and we were smoking like a chimney. Good thing diesels like to work hard.

The Indiana State Trooper slowly closed rank, trailer by trailer and when he got to my driver's window, he looked at me and slowly shook his smoke-the-bear hat side to side and drove on by grinning.

skip.