Hot wheel bearings

Jim, thanks.

So the key answer to my questions, and pointers for the OP, a

“For safety anyway, the threshold of the brake activation is set so that going down hill, even if you are in low gear to slow you down, in a correctly set up and maintained over-run system the trailer or caravan’s brakes should not activate… if they did, there is a chance on a long decent in low gear they could overheat.”

I noted with interest this, too:
---------
“The Future

“As towing vehicles become lighter and trailers and caravans become heavier, there is increased likelihood the towing to the limit of any tow vehicle will become more frequent. Already in Australia and New Zealand, it is now mandatory to have power assisted systems for trailers above certain weights… the same in America and Canada. There are a number of options on the market… AL-KO has had its “Sensabrake” system since 2009 in Australia and New Zealand and in the USA and Canada, there are dozens of companies that offer electronic braking systems.

“In Europe, currently there is the AL-KO ATC system, which is more an electronic stability aid than a full-fledged braking system.”
------
Chris N

Yeah, it's braking on the downhill and wheel gets incredibly hot and takes a while to cool down because its a significant thermal mass. Anyways, whenever I am going to drive in hot conditions on significantly hilly terrain, I'll disable the surge brake. I have a special piece of wood that I can insert in the tongue to prevent the damper from moving and subsequently engaging the brake. Obviously, do this only if your tow capacity is greater than the weight of the trailer.

On 18/06/2013 18:39, Jim White wrote:

Interestingly the Alko manual suggests that if the brakes are coming on
when going downhill or decelerating then the overrun damper is faulty.
Excerpt from manual:

BRAKES APPLY DURING
DECELERATION OR
DOWNHILL TRAVEL
Overrun damper is defective. Replace the overrun damper.

That makes no sense at all.

When under way, the ONLY time my Cobra's brakes apply is during
deceleration or downhill travel and if they didn't, THAT would be a defect.

That's why the whole expensive and tricky sliding tow hitch is fitted.

GC

On 18/06/2013 21:35, Jim White wrote:
At 10:46 18 June 2013, Chris Nicholas wrote:
I meant during braking vs gravity or normal deceleration. C

try this
http://caravanchronicles.com/guides/...brake-systems/

Jim, Chris, with an overrun-braked trailer, there is NO such thing as
"braking" except from "gravity or normal deceleration".

GC

GC, I know only what I read but it makes sense to me. The point is that the spring rate is such that gravity on slopes up to some pitch (unstated) and normal slowing down without the use of brakes does not compress the spring and activate the trailer brake; whereas the (greater) g developed by applying the car brakes does compress the spring and activate the trailer brakes.. Have you read the full article Jim referred to?

Regards – Chris N

On Wednesday, June 19, 2013 12:27:40 PM UTC+2, Chris Nicholas wrote:
GC, I know only what I read but it makes sense to me. The point is that the spring rate is such that gravity on slopes up to some pitch (unstated) and normal slowing down without the use of brakes does not compress the spring and activate the trailer brake; whereas the (greater) g developed by applying the car brakes does compress the spring and activate the trailer brakes. Have you read the full article Jim referred to?



Regards – Chris N

I think the problem with the overrun damper and overheating is that with a defective damper, the brakes do not release properly, unless you accelerate suddenly and powerfully after braking. If you slowly bring the entire train up to speed, the brakes may stay on, and overheat. I had exactly that with my Cobra, and now I have a new overrun damper lying around, until I get around to installing it..

Soar & drive safely,
Lars Peder

On 19/06/2013 20:27, Chris Nicholas wrote:
GC, I know only what I read but it makes sense to me. The point is
that the spring rate is such that gravity on slopes up to some pitch
(unstated) and normal slowing down without the use of brakes does not
compress the spring and activate the trailer brake; whereas the
(greater) g developed by applying the car brakes does compress the
spring and activate the trailer brakes. Have you read the full
article Jim referred to?

Regards – Chris N

Chris - I hadn't when I wrote and was puzzled about 'braking' that
wasn't 'deceleration'. I have now and I see the point that was being made.

GC

Is anyone aware of a US source for the overrun damper as described in the recent post by Lars?