Changing trailer springs

[Jono_SS]

or in my case, changing the hanger at the rear end of the spring...

I have a slightly longer hanger to fit, as the tyres were occaisionally rubbing on the inside of the wheel guard when i went over a good bump.

has anyone got any tips I should take notice of when undoing the springs from the trailer?

for example, should I undo the springs from the axle?
which bits of the trailer should I jack?

I can't take the boat off, unfortunately

I know it's easy in theory...

[Blackened]

G'day

Is it over or under sprung? Either way, jack and put stands under the chassis of the trailer, enough to support it.

Do the same with the axle but only when the springs are under no load.

Drop the axle bolts first (2 U bolts either side) and make sure axle is clear.

Drop the shackle bolt for the spring to drop out and then the pin at the front.

Just be careful when you do this, have a mallet on hand and a good set of sockets/shifter/breaker bar and some inox.

It will be easier if you can drop the boat off and turn the trailer upside down

Dave

[SunnyCoastMark]

Hey Johnno,
Something doesn't sound right here:-

1) It would be unusual for a single axle boat trailer to have shackle springs - they almost always have slipper.

2) Which means that you would have a slipper box at the back - so a longer hanger would do nothing.

3) Either way - the hangers are welded on so replacing them requires grinding, rewelding and re galvanising.

Can you post a photo?

Mark

[Jono_SS]

i guess it could be my incorrect terminolgy....

here is a photo of the rear setup showing how the springs are schackled to the chassis...

[SunnyCoastMark]

Well - there you go - it does have shackle springs.

OK - you have a couple of options - both pretty simple.

1) put the axle under the springs - this will raise the trailer by around 60-70mm which will give you plenty of clearance under your guards. Will make a slight difference in launching - but being a tinny - it shouldn't be too bad.

2) You should be able to get some longer shackle plates. (the plates connecting the hanger to the spring). Not sure where you are located - but anyone such as ALKO, Active Fab, All Trailer Spares or trailer manufacturer should have them ar be able to source them.

and one more

3) Change your wheels to a smaller size (last resort though - expensive)

Hope that helps,

Mark

[Jono_SS]

thanks mark.

i already have the longer shackles, so was looking for advice on the "sequence" of supporting bits of the trailer before undoing others, if you know what I mean.

regards.

Jono

[SunnyCoastMark]

Hey Jono,
OK having a forklift makes this job easy. Obviously you don't - so best thing to do is jack the trailer up and support it on stands or drums or builders trestles - whatever you have so that the wheels are off the ground (enough to allow for the longer shackle plates).

The next step you can do either way round (whatever you feel more comfortable with)

Undo the bottom bolts each side and lower the axle/spring assy - (it may stay in place if the front hangers are tight).

Undo the top bolts and remove the shackle plates.

Fit the new plates to the hangers (top bolts) - tighten the bolts firm so that you can still move the plates but tight enough so that you have to push or tap the spring in place (so that it holds itself in place).

Insert the bottom bolts.

Tension all of these bolts so that there is no end play in the assembly, whilst still allowing them to pivot.

Jack up - remove stands, road test.

Job Done.

Hope that helps.

Mark