Axle Carriage

[Bayou Dave]

I have a 21' pontoon boat with a tandem axle. There is zero and maybe negative tongue weight. I believe I should move the axle carriage back to get some tongue weight. My question is, what is the safest way to do this?

 

[bruceb58]

Have a picture of your trailer?

 

[Bayou Dave]

Have a picture of your trailer?

This is just before I bought it a few weeks ago.

 

[bruceb58]

Looks like the current axle setup is welded?

Are there brakes on that trailer?

 

[Bondo]

Ayuh,... If the carriage is held in-place with U-bolts, loosen 'em, 'n slide it back,....

I like 10% minimum, to 15% of the weight on the tongue,.... good ride, 'n good control,....

 

[Bayou Dave]

Bruce. It is not welded The carriage has u-bolts holding it to the frame. No brakes. From what I can figure out the total weight is under 3000 lbs and brakes are not required, even though brakes are a good idea.

Bondo. I have read that a tandem axle % should be around 5% to 7% and single axles around 10% to 15%.

With the carriage movable what would be a good procedure for moving it? Remove the u-bolts completely, lower the tongue and put jack stands under the rear. Then jack up the tongue? Or jack the tongue first and put it onto jack stands. Then jack the rear onto jack stands? Or jack the axles,etc?

 

[mla2ofus]

The tlr appears to be made to fit a shorter 'toon. It should still be workable. Leave the tlr hitched to the tow vehicle and jack up each rear side 'til the tires just clear the concrete/asphalt. From what I can tell in the pic you may have to move it further back than needed so the rear U-bolt will clear the next to rear crossmember.
Mike

 

[bruceb58]

What I would do is this:

1) Weigh your entire setup as is so you can determine what weight you want on your tongue.
2) Measure your existing tongue weight with a bathroom scale and lever set up.
3 Jack up both sides of the trailer at the equalizer pivot and verify that the tongue weight stays the same or close to the same.
4) Jack up the trailer at various points further back equally on both sides of the trailer until you get your desired tongue weight. That is the new point where the equalizer will be.

 

[Bayou Dave]

Mike. The axle carriage is 2 1/2" from that crossmember u-bolt you mentioned. I probably will have to move the carriage past it.

Bruce. Part of my problem is that I have zero tongue weight now to measure. The tongue will not stay down without my standing on it. It is like the axles are right at the equalizer point. I am hoping that by moving the axles back a few inches I will have some tongue weight to measure and go from there.

Dave

 

[Bayou Dave]

The tlr appears to be made to fit a shorter 'toon. It should still be workable. Leave the tlr hitched to the tow vehicle and jack up each rear side 'til the tires just clear the concrete/asphalt. From what I can tell in the pic you may have to move it further back than needed so the rear U-bolt will clear the next to rear crossmember.
Mike

Mike. Wouldn't leaving it on the hitch put an awful lot of weight on my truck when I jack up the rear of the trailer? It seems like it would be a lot more than the 500 lbs max tongue weight my hitch can have.
Dave

 

[bruceb58]

Bruce. Part of my problem is that I have zero tongue weight now to measure.

No problem...skip test 2 and 3. Just set up a scale to measure the tongue weight.

 

[Scott Danforth]

if your at the ballance point now, you will most likely need to move the carriage 6" or more rearward.

 

[lckstckn2smknbrls]

Would the scum line on the pontoons lead anyone to think there is a lot of water in them?

 

[Bayou Dave]

Would the scum line on the pontoons lead anyone to think there is a lot of water in them?

I have had the boat out twice and there is no evidence of water in the toons. The scum ine is part scum line and part black paint that has worn off quite a bit.

 

[Scott Danforth]

Would the scum line on the pontoons lead anyone to think there is a lot of water in them?

my guess is the fuel tank and batteries sit in back. put two peoples up front and she will level out.

 

[bruceb58]

my boat sits higher than that with a 90HP motor but every pontoon is different.

 

[mla2ofus]

Mike. Wouldn't leaving it on the hitch put an awful lot of weight on my truck when I jack up the rear of the trailer? It seems like it would be a lot more than the 500 lbs max tongue weight my hitch can have.
Dave

I was just thinking of side to side stability. You can leave the tongue jack down while jacking up the rear. Just put some weight on the tongue jack slightly lifting the truck. As you jack it up some weight will be transferred back to the truck. As close as the jack is to the hitch there won't be much transfer.

Mike

 

[Frank Acampora]

I can not see the cross member that you describe the carriage needs to pass. However once you do move the carriage backward, MEASURE from the rear axle to the back of each frame side tube (assuming they are equal length. THEN, MEASURE diagonally across from axle to opposite end of tube. Diagonal measurement MUST be exactly equal Repeat measurements from front axle. If either measurement is not equal then look for bent structural members. Axles MUST be true on the frame for the trailer to track straight and avoid excessive tire wear. If the frame members prove to be unequal in length. measure to the coupler.

 

[Snowfish]

My question is, what is the safest way to do this?

Remove the boat from the trailer. That's the safest, easiest way. There's 4 u-bolts holding the axle cradle. Loosen and move axle back a full foot. You should be able to do this at the landing. Provided the boat is moored out of the way. Moving the cradle back a full foot will not give you too much tongue weight. We over think these things sometimes.

 

[bruceb58]

When I replaced my axle on my 24' cuddy cabin boat, I just supported the trailer with 4 jack stands. It would definitely be easier if you took the boat off but you can do it with it on there.