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wayno60
14-10-2012, 09:10 PM
As you know i just got the 70yam fitted to the 4.75 bluefin. The prob i have is that it seems, well infact it IS rear heavy. I know theres nothing else in the boat atm but as i lift it off the tow bar she,s very light with hardly no weight on the ball.
On the way home on friday it towed like a dream, no swaying at all.

Its that close to balanced i cant walk down the stern as it will tip up...when on the jockey wheel.

I had a squiz under the trailer and i could move the whole suspension back about 5 in, cant hurt can it??
plus once the usual shit go's in that should sort it?????

deckie
14-10-2012, 09:43 PM
geez that must have been a bit disconcerting balancing like that. Shouldnt have been THAT much diff in weight.
Could you lift it off the tow ball single handed before the new donk ?
You sure they didnt sneak half a dozen old 200Ahr AGM's onboard and hide them down back as well ? ;D
I'd say u might be moving the axle back, hopefully one of the trailer experts in here sees this asap.
Good luck..sorry cant help coz feel its a job for an expert to get right first up.

wayno60
14-10-2012, 09:52 PM
Bud its a new trailer to this boat, the boat that was on this trailer was a half cab glass so plenty of weight up the front.
All the suspension is bolted to its own frame and the frame of the trailer bolts to that., So it just a matter of undoing 8 u bolts and slide the wheel, axel, spring assemble back 5 inchs. ill get a pic tomorrow.

barra71
15-10-2012, 12:00 AM
Hay wayne i had to do the same when i got mine fitted mate. I moved the axel back 4" and she was all good. towes good after i moved it back and good weight on the ball now and no sway.

Chas & Clarry
15-10-2012, 05:28 AM
I realise that this is not always possible and that you probably already thought of it, but is it not easier to move the winch forward a bit? We did this on a previous boat and 75mm made an enormous difference.

Tim and Trace

NAGG
15-10-2012, 05:54 AM
Yeh - you clearly need to move the axle back .... .the wondering all over the road was a good indicator that there was not enough weight on the tow ball .

Chris

purnong
15-10-2012, 06:13 AM
I would put all your gear in first and see what it's like then look at moving the axle back
Mate had to do the same thing recently with a 4.1 Brooker after he changed from a 30hp manual start to a 40hp electric start PTT
Actually he is now having problems with the boat being arse heavy in the water as well, Hopefully you should be Ok there

Fed
15-10-2012, 06:28 AM
The swaying doesn't usually kick in until 80-90KPH and more often than not it's when you're going down a hill.
Not what you'd call the best time to find out you've got a problem.
You might have dodged a bullet Wayno.

wayno60
15-10-2012, 07:33 AM
the wondering all over the road was a good indicator that there was not enough weight on the tow ball .



On the way home on friday it towed like a dream, no swaying at all.



nagg mate you reading the same post......:)

T and T,
My drive way from the road to the house go's up hill so as i reverse in the gap between the bow spit and the back window of the canopy on the ute decreases to the point that im not willing to take a chance of popping a hole in the rear window. Moving the winch post forwards will only increase the problem. so the axels it is..

propdinger
15-10-2012, 08:17 AM
you will have to move the axle back which is no big deal just undo the ubolts and jack it up and move the axle back. that's exactly why they are made the way they are cause every boat is different i bought a new trailer recently and had to move mine around a few times to get where i was happy.

Triple
15-10-2012, 08:25 AM
If you are going to move the axle, do it right the first time and make sure the tow ball weight is around 10-15% of the ATM (whatever your usual load is). Saves adjusting it numerous times to get it feeling right.

wayno60
15-10-2012, 03:28 PM
Triple, so is that all you need ? i really thought it would have been more than that....

Anyway heres the trailer
8510085101851038510285099

in pic 2, that bar that the rope is tied off to is the frame for the susspension, just undo the u bolts and slide back......thats my thinking.

Kero
15-10-2012, 03:51 PM
How far forward, from the transom, is that rear roller? From the last pic it looks to be a lot of boat overhanging the last rollers!

Greg P
15-10-2012, 04:03 PM
I would move that winch post forward a few inches and check the weight on the jack. It may just be enough rather than rooting around with the axle.

NAGG
15-10-2012, 04:08 PM
nagg mate you reading the same post......:)

T and T,
My drive way from the road to the house go's up hill so as i reverse in the gap between the bow spit and the back window of the canopy on the ute decreases to the point that im not willing to take a chance of popping a hole in the rear window. Moving the winch post forwards will only increase the problem. so the axels it is..

Sorry - misread it ......... but if it is as balanced as you say then it is actually not a good set up for towing & specially at speed . A boat of that size (wt) - an average bloke should pretty well be able to step up on the transom without the boat tipping up (close to it anyhow)
This should be checked with your normal gear / fuel on board though

Chris

GBC
15-10-2012, 04:17 PM
It does look like the boat isn't far enough onto the trailer. Maybe investigate extending the draw bar a couple of foot and moving the winch post forward? You'll end up with the transom properly supported, the wheel further back in relation to the boat,c and a longer first class lever on the trailer.

stevej
15-10-2012, 04:22 PM
similar size boat i can fill my lifewell and have the 2 kids and me jumping around the back

move the axle back and winch post forward, id go as far to say as that trailer is .5 of a m too short and no brakes ?

hull 400kg
outboard 120kg
battery 30kg
anchor rope 30kg
safety gear 10kg
fuel 60kg
trailer 240kg
spare and bracket 20kg

910 there before you add any electronics eskys fishing gear and so on
that would have to be bordering on an illegal setup with nothing in the boat

wayno60
15-10-2012, 04:37 PM
from the rear roller to ther back of the boat is 300.

Just had a quick squiz and making the draw bar say 400mm longer would bring the boat fully onto the trailer and give me another 100 betwen the bow and the back window of the ute. kill two birds with one stone.

barra71
15-10-2012, 06:26 PM
from the rear roller to ther back of the boat is 300.

Just had a quick squiz and making the draw bar say 400mm longer would bring the boat fully onto the trailer and give me another 100 betwen the bow and the back window of the ute. kill two birds with one stone.

Thats what i would be looking at Wayne, could be the better way to go mate.. still looks like a great setup..

wacoaus
15-10-2012, 08:02 PM
This is starting to get me slightly concerned as my boat and trailer (once off towball ) can be lifted with one hand that easy it feels almost dead even in balance and its an old 4.5m fibreglass runabout so not the lightest.
Can't move axle back as is already in the last set of holes and have taken off the easyload guide rollers? that were on it when I bought it and moved winch post forward until only 2 inches of boat sticks out past rear rollers yet would be lucky to have 20kg of weight on towball. I keep a carstand under the back of trailer in carport as I can put both hands on the outboard and lift the front off the ground.
Thing is it tows like a dream as except for the weight behind you , you wouldnt even know its there and thats towing it with a lancer at a hundred

Kero
15-10-2012, 08:10 PM
from the rear roller to ther back of the boat is 300.

Just had a quick squiz and making the draw bar say 400mm longer would bring the boat fully onto the trailer and give me another 100 betwen the bow and the back window of the ute. kill two birds with one stone.


300 overhang is too much.
Look into doing what you've written above!;)

NAGG
15-10-2012, 08:11 PM
This is starting to get me slightly concerned as my boat and trailer (once off towball ) can be lifted with one hand that easy it feels almost dead even in balance and its an old 4.5m fibreglass runabout so not the lightest.
Can't move axle back as is already in the last set of holes and have taken off the easyload guide rollers? that were on it when I bought it and moved winch post forward until only 2 inches of boat sticks out past rear rollers yet would be lucky to have 20kg of weight on towball. I keep a carstand under the back of trailer in carport as I can put both hands on the outboard and lift the front off the ground.
Thing is it tows like a dream as except for the weight behind you , you wouldnt even know its there and thats towing it with a lancer at a hundred

If you can lift a boat at the hitch with one hand ..... then yes it's a concern - a 500kg package is best with around 60-70kgs on the ball .
I'm renovating my old boat atm ....... I've removed everything (except the motor) = at 80km it tows like a bitch - the 110kgs of batteries / leccy that were in the bow section are the difference between the death wobbles and 120kmph - stick like the glue

Chris

wacoaus
15-10-2012, 08:24 PM
Thanks Chris,
I usually on longer trips I usually load everything i can with weight in front of axle and take fuel in jerrycans and put them up front and fill main tank when i get there as it is bolted in and cant move it. I may have to drill another set of holes in trailer to move axle back further but I dont realy want to as at the moment it has no wobble in it at all and thats even at 120 overtaking trucks.
Am just concerned that if I move it I will end up with death wobbles. But at the moment the jockey wheel is just decoration as you can unhitch it and move it around the yard with one hand on hitch holding it up and one on bow of boat steering it

wayno60
15-10-2012, 09:17 PM
im on it kero...

Gon Fishun
15-10-2012, 09:27 PM
You will find most single axle boat trailers tow well without a lot of weight on the tow ball. The reason being if you look at a boat trailer, the distance from the tow ball to the axle is greater than , say a box trailer , which jiggle about, and are twitchier to reverse.

Camhawk88
17-10-2012, 06:55 AM
similar size boat i can fill my lifewell and have the 2 kids and me jumping around the back

move the axle back and winch post forward, id go as far to say as that trailer is .5 of a m too short and no brakes ?

hull 400kg
outboard 120kg
battery 30kg
anchor rope 30kg
safety gear 10kg
fuel 60kg
trailer 240kg
spare and bracket 20kg

910 there before you add any electronics eskys fishing gear and so on
that would have to be bordering on an illegal setup with nothing in the boat

Thats not bordering on illegal- it is illegal. 750kg is the max permissible un-braked towing weight in QLD. Might need to invest in some brakes as well.

Looking at that trailer it appears to be too small for the boat. As mentioned the rear overhang is way too much and looks like it may well damage the boat at either the contact points with the rear rollers or the transom itself. The winch post looks to be about as forward as you could get it without the bow sprit kissing the back of the car too.
So to fix you are looking at extending the draw bar, fitting a sliding coupling, brakes disks and callipers- could be rather costly.
If it were me I would probably investigate getting a new trailer that fits.

wayno60
26-11-2012, 06:25 PM
Ok the draw bar has been extended by 400 bringing the boat right up onto the trailer. The winch post is 300 forward from where it used to sit. Now im more happy with the weight on the tow ball and the whole set up.
8657586576

SunnyCoastMark
26-11-2012, 08:38 PM
Hey Wayne,
Certainly looks a lot better on the trailer.

How did you extend extend the drawbar? Did you cut it & add a longer section?

If so, did you plate each side of the join? Sorry, I can't see in the photos.

Mark

wayno60
26-11-2012, 11:12 PM
Hey Mark,
No i didnt plate either side of the join, but its been sleaved on the inside. It go's from half way between the jockey wheel and the hitch to past the spare wheel.
It was bolted solid before i welded it so i cant see it coming adrift to easy.

do you still think plates on either side are needed??

cheers

Spaniard_King
27-11-2012, 05:41 AM
Wayno,

Have you put this over a weigh bridge??

If its over 750kg and you have an accident your fault or not you risk no insurance for your car and boat!!

finga
27-11-2012, 06:34 AM
Also get the rego papers sorted out.
They'll need to remeasure it.

Feral
27-11-2012, 08:57 AM
Just put your fuel tank in the front and bung the spare on the winch post.

SunnyCoastMark
27-11-2012, 10:57 AM
Hey Mark,
No i didnt plate either side of the join, but its been sleaved on the inside. It go's from half way between the jockey wheel and the hitch to past the spare wheel.
It was bolted solid before i welded it so i cant see it coming adrift to easy.

do you still think plates on either side are needed??

cheers

If the sleeve has been properly plug welded along it's length - each side - then it should be OK. If it has only been welded at the join - then yes, it will definitely need plating.

Mark

wayno60
27-11-2012, 03:57 PM
thanks guys all good points that ill look into.

Blusta
27-11-2012, 06:23 PM
Yep. Move the axle back a few inches, not difficult; just mark the current position so that move each side back equally. Definitely need about 50 - 60 kg on the tow bar.