Help with trailer rehab and axle placement

[Decker83]

I have a 1983 Deckboat 18.5' on a unknow trailer.. When I bought the boat there was little to no tounge weight so I moved the
boat forward about 5"..

When I towed the boat home I could not get above 55 mph or the boat would start a real bad fishtale.. From other pics I
have seen of this boat it looks like the axle is to far forward.. The trailer has pre drilled holes to move the axle back but the first holes or about 6"..

Need to know what you guys think about this.. Here are a few pics of the boat on the trailer and some with it off the trailer.







Some pics of the axle..

 

[Decker83]

Re: Help with trailer rehab and axle placement

Also the leaf springs have 8 leafs.. I could not find a weight load on the axle.. Would anyone have a ideal on this..

In the pic you can see where the ubolts have hit the upper part of the frame.. Is this a sign of bad springs..

 

[sphelps]

Re: Help with trailer rehab and axle placement

Do you think they would have hit if the bolts were cut off flush with the nut ? Most axles from what I have seen sit on top of the springs. But I guess that would make the clearance issue even worse .

 

[Decker83]

Re: Help with trailer rehab and axle placement

Do you think they would have hit if the bolts were cut off flush with the nut ? Most axles from what I have seen sit on top of the springs. But I guess that would make the clearance issue even worse .

I don't know that much about how the trailer pulls.. Only pulled it 1 time and it was not good..

Both sides have some pretty good gouches from the ubolts.. I am going to replace the ubolts and will cut them off shorter..

Just don't know if the springs or still good or what to replace them with..

The boat is suppost to weight about 2200 empty without motor..

Northern Tool has some springs for sale here local so maybe I'll check with them if I don't get any response here..

 

[sphelps]

Re: Help with trailer rehab and axle placement

Decker do you think it may need another axle ? Dual axles ? That might spread the load out some and keep the u-bolt from hitting ..

 

[sublauxation]

Re: Help with trailer rehab and axle placement

Moving the axle back at least a foot and sliding the boat back flush to the bunks should cure your tongue weight and fishtailing problems. You should take the boat to a scale and have it weighted.

 

[Decker83]

Re: Help with trailer rehab and axle placement

Decker do you think it may need another axle ? Dual axles ? That might spread the load out some and keep the u-bolt from hitting ..

I have thought about adding a second axle but all the Deck Boats I have seen like mine only have 1 axle..

Moving the axle back at least a foot and sliding the boat back flush to the bunks should cure your tongue weight and fishtailing problems. You should take the boat to a scale and have it weighted.

Thanks sublauxation.. I agree with you about moving the axle back.. Nearly all of the ones I have seen online seem to have the axle back futher.. I don't think the PO had to tow the boat very far when he used it.. I could lift the tounge up and rest the motor on the ground with one hand and no effort..

I will take it to the scales but at the moment the hull is upside down on the cradle I built..

See the link below..

 

[kjsAZ]

Re: Help with trailer rehab and axle placement

as longer the distance between the coupler and the axle as better the trailer will track. US designed single axle trailers usually require a tongue load of 8-10% of the total trailer weight. If you want your trailer really run a lot better move the axle back until you have the 8-10% and then extend the tongue by 3ft without changing the location of the boat any more. Will give you lower tongue weight (good for the tow vehicle) and stability. The 8-10% have to be at the design point of the trailer and if you extend the tongue it's still there. Just as a reference:European trailers have to be designed for <4% tongue weight = much longer tongue.

The bolts hitting the frame won't be changed by the above. Looks like you are in for a new set of leaf springs which are rated for the weight. The other thing you could do as a temporary fix is to cut the U-bolts a bit shorter or to use shorter ones. They are REALLY long! The ones on my trailer (different type) only extend the nuts by 1/2".

Can you measure the tubing of your axle? That would give an indication of the weight capacity. Not accurate but at least a ball park.

 

[Decker83]

Re: Help with trailer rehab and axle placement

Thanks kjsAZ.
This is the kind of information I was looking for..
I am taking the axle lose from the trailer this weekend and will remove the wheels and measure the spindle..
I should get a good ideal of the weight capacity by the spindle and bearing size..


Thanks again for all your input..
Have a great Memorial Day weekend..

 

[colbyt]

Re: Help with trailer rehab and axle placement

Also not definitive but how many lug nuts and the spacing. That combined with the axle dimensions will narrow down the trailer capacity.

 

[kjsAZ]

Re: Help with trailer rehab and axle placement

from the picture(s) it looks like 5 on 4.5. That comes from 1500lbs to 5000lbs axles....

Good luck with restoring the trailer and boat! You will have some work ahead of you.
One tip: if you want to have the longer tongue you can use one of these folding tongue hinges and install them where the coupler is mounted today. Anything in front of it will make your tongue longer and you can fold it away when you store it.

I am currently looking for a new hinge as the one I have only allows 4ft of extension and I want to go up to 6ft. So far no luck.

 

[BobGinCO]

Re: Help with trailer rehab and axle placement

Do you know what your tongue weight is right now?
It SHOULD be about 10% of the weight of the trailer plus the boat.

So if the trailer and boat weigh 3,000 pounds, your tongue weight should be 300. If it's still too light (which appears to be true because of the fishtailing), then yes, move the axles back 6 inches and measure the tongue weight again.

 

[colbyt]

Re: Help with trailer rehab and axle placement

I am currently looking for a new hinge as the one I have only allows 4ft of extension and I want to go up to 6ft. So far no luck.

48" is the max for all tongue sizes with the Fulton Hinge and I am fairly sure they still have patent protection of the hinge so that make them the only game in town.

 

[hungupthespikes]

Re: Help with trailer rehab and axle placement

The marks on the frame could have been a one time bottoming out. An overloaded boat or even the trailer was used for hauling something else that was way over the limits of the trailer.

Without knowing the history of the trailer I wouldn't be too concerned about the bottoming out until you know a lot more.

Like any used trailer, it's time to go over it with both eyes wide open.

A swag, that the boat was used commercially and the PO had a good day/s checking the lines.

It sounds like you have a good handle on the situation and are going about it the right way. :thumb:

huts

 

[RobWise64]

Re: Help with trailer rehab and axle placement

Yes 10% tongue weight vs the loaded weight of the trailer and boat at a minimum, and if you can get 15% that's even better. If that boat weighs 2k, figure another 700# or more for the trailer. Eight leaf springs are uncommon, typically a 4 leaf rated at #1750 each would be plenty for that axle. And the leaves would be thicker than your current ones so the stack height of all the leaves together won't vary much. Measure that spring center eye to opposite center eye so you can see which ones are available. 25 1/4" - 27" are common lengths.

From the photo it looks like the plies are separating and the main (top) ply is doing all of the work. That's probably why you're bottoming out and I would replace it. A hard shock, like a road hazard, could cause it to break suddenly and finding a trailer spring in stock anywhere nearby while you're on the side of the road is no fun at all.

Rob

 

[RobWise64]

Re: Help with trailer rehab and axle placement

One more thing: That axle should have a #3500 rating. When you remove your hubs, your spindle is likely 1 3/8" for the inner bearing and 1 1/16" for the outer bearing. Those bearing numbers are L68149 (inner) and L44649 (outer). It is very common and finding parts for it is easy.

Rob