trailer wheels won't turn
chris
about 2 months ago and it was working fine at the time. Now the
wheels are immobile. I even tried to pull it with my car and the
wheels just dragged across the pavement.
In the dark of night I could not figure out if somehow the brake
shoes are suddenly rusted in place somehow or if the shock in the
hitch is jammed.
Both wheels are locked so it would be hard to think that is a
coincidence, the problem possibly started forward in the system.
However the actuation rod that goes from the hitch to the axel is
loose/ can be moved fore and aft.
Behind the actuation rod are the 2 cables that go to the brakes. It
seems that the problem from this point or beyond/behind.
I suppose it is possible there is a problem with bearings or that
somehow the brakes stayed partially engaged on my last tow.
Any suggestions on how to diagnose and fix it? / where to get parts.
Also is there a way to temporarily disengage the brakes, I was
thinking i could take out the brake pads etc.
thanks
Chris
Atlanta, GA, US
Peter Scholz
Chris,
probably the levers in the brake that are operated by the cables and
engage the brake pads have become stuck.
You can try several things:
1. the trailer brakes are supposed to automatically disengage when
pushing the trailer backwards. If there is room behind the trailer to do
that operation, try to push back the trailer with your car. This
operation might be enough to loosen the brake pads.
2. If not successful, get a medium hammer and make a few strokes on the
mounting disc (accessible from underneath the trailer, about where the
cables get into the brake). This might loosen the mechanism.
3. if not successful, there is an adjustment mechanism on the backside
of the brake mounting disc, usually either a small hole where you can
operate a small cogwheel with the aid of a screwdriver, or a bolt that
can be operated with an open-end wrench. You will have to try which
direction looses the brake and which direction engages it. Try to loosen
the brake using that mechanism. To find out if this works it is best to
jack up the trailer so you can turn the wheel without having to move the
whole trailer.
4. You might want to combine actions 1 to 3.
5. When you finally succeed, I strongly recommend to take off the wheels
and brake drums to inspect and clean the inside of the brake. Usually it
is enough to blow all the dirt out using pressurized air, and maybe
apply some heat resistant grease (carefully) to the mechanism that is
operated by the brake cable. This is also a good opportunity to look at
the wheel bearings and to re-grease them.
You should get any parts for that axle at your Komet trailer dealer in
the US, however, if this should be a problem, I can assist you in the
process of ordering any parts you might need. There should be a metal
plate on the inside of each wheel (about where the cable runs into the
brake) stating the exact type of the brake.
Good Luck,
--
Peter Scholz
JE
Andy
> Also is there a way to temporarily disengage the brakes, I was
> thinking i could take out the brake pads etc.
If the wheels are locked by the brakes it is very unlikely that you
would be able to remove the drums,.and you can't remove the shoes
without removing the drums. The first step in fixing the problem will
have to be getting the brakes to release.
You say the brake rod is free to move. Can you determine if the
cables are under tension? It may be possible to feel slack in the
cable outers. If the cables themselves are seized it may be possible
to free them by working them sideways at the same time as lubricating
them.
If the cables are slack then the problem must be internal to the
drum. If all else fails squirting penetrating oil in every possible
opening may help. That's a last resort thought as you may have to
replace the contaminated shoes.
If pushing it backwards, as suggested by Peter, does not work then try
rocking the wheels backward and forwards. One way to do that would be
to pull the trailer tongue sideways in opposite directions as hard and
quickly as possible.
Of course this all assumes that you left the trailer with the parking
brake set. If not then check to see if anyone you may have upset
recently has welded the drums to the back plates.
Good luck!
Andy
chris
wrote:
> probably the levers in the brake that are operated by the cables and
> engage the brake pads have become stuck.
>
> You can try several things:
>
> 1. the trailer brakes are supposed to automatically disengage when
> pushing the trailer backwards.
> If there is room behind the trailer to do
> that operation, try to push back the trailer with your car. This
> operation might be enough to loosen the brake pads.
With my car I pulled the trailer forward about 1m then back a meter in
reverse. It took quite a bit of RPM/horsepower to drag the tires
across the cement, I was hoping going in reverse would have unlocked
it too but it did not.
> 2. If not successful, get a medium hammer and make a few strokes on the
> mounting disc (accessible from underneath the trailer, about where the
> cables get into the brake). This might loosen the mechanism.
By "mounting disk" do you just mean the main metal part that is
exposed inward [through which the cable goes]?
thanks
Chris
mattm
My Cobra trailer had been parked by the previous owner with the brakes
set.
Needless to say they rusted in that position. We were able to get it
to move
(finally) by backing off the brakes with an adjustment lever. There
should be
a port on the back side of the hub (the axle side of the wheel) with a
rubber plug.
Pull off the plug and you should see a toothed wheel in there. You
can move that
with a screwdriver to back off the brakes.
-- Matt
Peter Scholz
>
> By "mounting disk" do you just mean the main metal part that is
> exposed inward [through which the cable goes]?
>
Yes. 'Back plate' (as mentioned by Andy) would probably be the more
precise term. This plate is quite strong, as it acts as the counter part
when braking the wheel, so it can stand a bit of beating...
Peter
sisu1a
> shoes are suddenly rusted in place somehow or if the shock in the
> hitch is jammed.
> Behind the actuation rod are the 2 cables that go to the brakes. It
> seems that the problem from this point or beyond/behind.
>
> I suppose it is possible there is a problem with bearings or that
> somehow the brakes stayed partially engaged on my last tow.
>
> Any suggestions on how to diagnose and fix it? / where to get parts.
>
Sorry to hear about your bad luck. No suggestions, other than go
electric since it will prolly cost less to switch over than to fix,
and you get MUCH better brakes out of the deal. That work normal in
reverse. And don't freeze up when not used for a little while. And
don't need to be babied/greased/talked nice too etc. Should I change
my '10 reasons' to switch list my into '11 reasons' to switch to
electric brakes list? Nah, long term mechanical reliability is
already covered...
-Paul (eff surge brakes!) Hanson
JS
the cables due to lack of use and maintenance. Find something to spray
in the two cables.
WD-40, anything that claims to free rusted parts. Brake fluid if you
can get it in.
When you've got it clean keep it protected, especially as you live
where things go rusty. LPS-3 is my favorite rust inhibitor.
Jim
Darryl Ramm
Paul
Maybe one day you'll be maneuvering your trailer by hand on a gentle
slope and unable to control it and it will run over you. Then those of
us who like override brakes won't have to put up with your list
anymore ;-)
---
Where I keep my trailer in relatively dry conditions everybody leaves
the brakes on, the larger fear is the occasional strong wind, even if
the trailers are also chocked and well jacked. I've had several pilots
from the UK tell me that it is common at their clubs is to keep the
brake off because of this chance of seizure.
Darryl
Chip Bearden
if the problem is frozen cables or other parts of the mechanism, but
then you'll have to readjust the brakes to make them servicable for
driving. At least it should allow you to remove the drum for access to
the brake. I'm not sure it's corrosion in the brake mechanism that's
the problem so much as the shoes seizing/rusting to the drum over time
due to moisture. After too many first-flight-of-the-year sessions like
this, I no longer set the parking brake for long-term storage.
Chip Bearden (with experience on both Komet and Cobra trailers)
ASW 24 "JB"
USA
John Smith
> Where I keep my trailer in relatively dry conditions everybody leaves
> the brakes on, the larger fear is the occasional strong wind, even if
> the trailers are also chocked and well jacked. I've had several pilots
> from the UK tell me that it is common at their clubs is to keep the
> brake off because of this chance of seizure.
In Europe where manual gearboxes are still popular, most people know
that leaving the handbrake on for extended periods is not recommended.
In the USA with their authomatic gearboxes, this knowledge seems to have
got lost.
Mostly the problem is not corrosion of the cable but that the brake
shoes tend to somehow get "glued" to the drum. Forcing your trailer
backward may loosen the brakes, if you can do so without engaging the
override mechanism. Otherwise you may have to open the brake drums and
losen the shoes by hand.
rlovinggood
I missed seeing you at Cordele.
As Matt said, the previous owner of his trailer left the hand brake
on, and parked outside in the North Carolina rain and humidity for a
long time, the brakes seized. Backing off the star adjusters will
hopefully work. If not, you might end up having to take a torch to
the drum to try and break the grip that the rust has on the shoes.
Big hammer and a torch. Maybe. Get professional help!
Before seeing that trailer end up with locked brakes, I didn't set my
hand brake. After seeing the trouble the previous owner went through
and the expense of finally getting it fixed, I NEVER set my hand brake
for more than a few hours. Now, I just use the hand brake when
maneuvering the trailer on a slight slope for a few inches as I
connect it to the car. When I have the trailer where I want it, I'll
chock it and tie it down. But I'm not setting the hand brake!
Good luck!
Ray Lovinggood
Carrboro, North Carolina, USA
A.Bus Driver
suggestion is to jack up the trailer, remove the wheels and use a 10
lb hammer to strike the circumference of each drum. I've used this
many times to remove brake drums on cars.
Good luck,
George
Michael Huber
>cables are under tension?
Is the hand brake lever nearly vertical when the brake is engaged? I once
had exactly the same symptoms with a relatively new Swan Trailer. There is a
rod that connects the brake lever in front to the flat bar that distributes
brake force from the rod to the cables. Due to run - in wear of the brake
pads the rod moved too far forward when pulling the brake lever and popped
out of its support and jammed. It took me some time to find that ...
Michael
chris
7am to the neigbors delight. The first side released after hammering.
The second side was harder, I hammered but it did not release until
after rolling the trailer back and forth. The top shoe was jamming on
that side. I could see that the lower shoe was not in contact with
the drum.
All in all it turned out to be just a few minutes and all is good
now. I did not have to jack up the trailer or take the wheels off.
Thankfully I got lots of good advice from RAS.
I should get better gas mileage with wheels that turn.
The trailer has been sheltered from rain. All this rusting must have
just been from 2 months humidity [in ample supply].
I did not find a slot to adjust a star wheel. I have done that on
cars in the past so I know what to look for. This design has 2 slots
but they are for the spring to hook through.
I never did figure out what the bolt was for, shown in the 2 o'clock
position in the photo:
http://gliderpilot.org/Temporary
On both sides there were small viewing holes to see if the shoe was in
contact with the drum [shown in the 10 & 5 o'clock position]
I suppose I should soon take the drums off and lubricate the sides of
the shoes/mechanism [not the face that touches the drum].
I don't know if the mechanism or the face of the shoe and the drum
surface that rusted together.
Thanks guys!
Chris
Peter Scholz
> I used a 1 lb /.45kg hammer and hit both brake mounting plates before
> 7am to the neigbors delight. The first side released after hammering.
> The second side was harder, I hammered but it did not release until
> after rolling the trailer back and forth. The top shoe was jamming on
> that side. I could see that the lower shoe was not in contact with
> the drum.
>
> All in all it turned out to be just a few minutes and all is good
> now. I did not have to jack up the trailer or take the wheels off.
> Thankfully I got lots of good advice from RAS.
> I should get better gas mileage with wheels that turn.
Good to hear that it worked out well.
>
> The trailer has been sheltered from rain. All this rusting must have
> just been from 2 months humidity [in ample supply].
>
> I did not find a slot to adjust a star wheel. I have done that on
> cars in the past so I know what to look for. This design has 2 slots
> but they are for the spring to hook through.
>
> I never did figure out what the bolt was for, shown in the 2 o'clock
> position in the photo:
>
> http://gliderpilot.org/Temporary
nice shot. Your brake seems to be in a very good state, compared to
others I have seen here in Germany.
You have KNOTT brake. The bolt opposite the cable inlet is for adjusting
the brake, e.g. to compensate for pad wear. It has the same function as
the star wheel used on other types.
The instructions (partly) from KNOTT to do the adjustments are as follows:
Make sure that the rod and cables are under no tension.
Turn the adjustment bolt clockwise until the wheel cannot be turned any
more or turns very hard. (Turn the wheel only in Forward direction, as
the brake loosens itself automatically when turning the wheel backwards)
Then loosen approx. 1/2 turn counter-clockwise until the wheel turns
free again. a slight scratching noise doesn't harm,
A complete inscruction as well as diagrams of the inside ofthe brake can
be found here (only german, I'm afraid):
http://www.boeckmann.com/pferdeanhaenger_allgemein_66564.html
Peter Scholz
ASW24 JE
Chris Reed
> You have KNOTT brake.
I have a KNOTT trailer, which I presume has KNOTT brakes as well.
Sometimes after standing over a humid winter one or both brakes locks
on. The solution is a hammer (I now keep a 4 lb club hammer in the
trailer). Jack up the offending wheel, give the head of each wheel nut a
firm tap, rock the wheel, repeat until it frees.
I've had the brakes checked out by a garage (auto repair shop in US?)
and all is fine, but this still happens. My guess is that somewhere in
the brake mechanism is a narrow clearance which tends to lock up with
corrosion.
The wheel won't free up if I don't jack it off the ground (well, not
without hitting it harder than I care to), but jacked up it usually
frees before I've tapped every wheel nut. Obviously, hit the nuts
square-on so as not to round them over.
Morgans
"Chris Reed" <chris...@NOSPAMqmul.ac.uk> wrote
>
> I've had the brakes checked out by a garage (auto repair shop in US?) and
> all is fine, but this still happens. My guess is that somewhere in the
> brake mechanism is a narrow clearance which tends to lock up with
> corrosion.
Most all drum brakes on automobiles have strong springs that forcibly pull
the brake shoes away from the drums, nearly all of the way. Only a small
part of the pad would be touching the drum in one small area of each shoe.
That is when the adjusters are working well and are keeping the pads out as
far as they are able. Most are not working well, and have a good bit of
slack that the brake piston has to take up when you press on the brakes. A
shoe in this condition does not have enough contact area with the shoe and
drum to rust together.
I am not familiar with this particular model of brake, but with most cable
actuated brakes, there can not be a lot of clearance from the drum, or the
cable movement would be too small to take up the slack and apply the
stopping pressure. It is the nature of the beast that the design must have
the shoes in closer contact to the drum, thus increasing the likelihood of
the two parts rusting together.
It might be a good idea to back off the adjusting nut, or star wheel
(whatever your model would have as an adjuster) before parking the trailer
for the winter.
--
Jim in NC