Everso advanced braking techniques

codprawn · 22 June 2007, 12:15

Quote:

Originally Posted by jwalker

Never be tempted to tow without brakes. Earlier in the season I towed my boat/trailer but the tow hitch didn't function correctly which prevented the brakes operating. (I didn't realise there was a fault, honest, officer.) The tow vehicle is a Disco, the road surface was damp and when braking firmly coming up to a busy main road junction, extra pedal pressure was needed to cope with the lack of trailer braking. The Disco wheels locked and the weight of the trailer just shoved the Disco along on the damp surface. A bit of cadence braking saved the day but my heart beat speeded up a bit I can tell you.

Why were you breaking firmly? That's what gears are for. Obviously you will still need some braking but most can be done with the engine - just remmber to blip the throttle on downchanges!!!

codprawn · 22 June 2007, 12:16

Quote:

Originally Posted by Sarah G

I think I would feel happier having a braked trailer anyway to be honest. Our Disco is a S1 and the brakes are not the best I've ever used (other car a Saab and we have a real culture shock if you jump out of one into the other. Either over braking in the Saab or having too many heart stopping moments in the Disco!!

Nothing wrong with Disco 1 brakes. They are disks all round. Either you have a problem or not a heavy enough foot. Anyway you shouldn't be using the brakes!!!

simmons0 · 22 June 2007, 12:18

Quote:

Originally Posted by codprawn

Why were you breaking firmly? That's what gears are for. Obviously you will still need some braking but most can be done with the engine - just remmber to blip the throttle on downchanges!!!

Bit of heal n toe in your disco eh Cods

codprawn · 22 June 2007, 12:43

Quote:

Originally Posted by simmons0

Bit of heal n toe in your disco eh Cods

Too right!!!

jwalker · 22 June 2007, 12:49

Quote:

Originally Posted by codprawn

Why were you breaking firmly? That's what gears are for. Obviously you will still need some braking but most can be done with the engine - just remmber to blip the throttle on downchanges!!!

What pish you can talk, Codders. We discussed this at length a while ago. And, it's an auto so blipping the throttle isn't necessary.

codprawn · 22 June 2007, 12:51

Quote:

Originally Posted by jwalker

What pish you can talk, Codders. We discussed this at length a while ago. And, it's an auto so blipping the throttle isn't necessary.

Ahh that makes engine braking more difficult but did you change down the box manually or just rely on the brakes?

Pish??? Saved me on many an occasion when towing heavy loads or driving on slippery surfaces!!!

jwalker · 22 June 2007, 13:05

Quote:

Originally Posted by codprawn

Ahh that makes engine braking more difficult but did you change down the box manually or just rely on the brakes?

Pish??? Saved me on many an occasion when towing heavy loads or driving on slippery surfaces!!!

Yer, right. So you find yourself going down a brae towards a busy main road with 5½tons of rig, you apply the brakes normally to find the trailer brakes inoperative. Are you suggesting you'd stick your Disco into 2nd gear and expect that wee diesel engine to stop you?

Codders, I do sometimes agree with your sentiments but you loose grip on reality occasionally.

jwalker · 22 June 2007, 13:07

I've done it again...forgot to take Jono's advice.

Jono · 22 June 2007, 13:07

.."Brakes to slow, gears to go"....

codprawn · 22 June 2007, 13:13

Quote:

Originally Posted by Jono

.."Brakes to slow, gears to go"....

Tell that to someone coming down the Alps with a 44 ton load......

http://en.wikipedia.org/wiki/Compression_brakes

The advantage of using the engine to dissipate energy is this immediate ejection of energy. Hot gases are ejected from the vehicle very quickly and the gases also transfer much of their heat directly to engine parts. In addition, friction produced within the engine system also adds heat to the engine parts.

This engine heat is taken away by the engine's integrated cooling system: usually a liquid circulation system and a radiator. Disc or drum brakes have no such energy dissipation mechanisms. They must rely on air flow to remove heat and they use their mass to retain heat without producing temperatures that would deform and damage the brakes.

Placing a vehicle in a low gear causes the engine to have more leverage (mechanical advantage) on the road and the road to have less leverage on the engine. This is what allows cars to slow down using their relatively flimsy engine parts. The engine maintains a high rotational speed to dissipate a lot of power without forcing too much strain on the engine.

codprawn · 22 June 2007, 13:16

Quote:

Originally Posted by jwalker

Yer, right. So you find yourself going down a brae towards a busy main road with 5½tons of rig, you apply the brakes normally to find the trailer brakes inoperative. Are you suggesting you'd stick your Disco into 2nd gear and expect that wee diesel engine to stop you?

Codders, I do sometimes agree with your sentiments but you loose grip on reality occasionally.

No I would have changed down FIRST!!!

I agree an automatic doesn't have as much engine braking as a manual but it still helps a lot - too many people just leave them in Drive.

Obviously you will still need the brakes but you shouldn't rely on them too much. Remember you also have low range to play with although you do ned to be stopped before you can engage it.

Of course if someone pulls out suddenly in front of you engine braking isn't going to do you - or them - much good!!!

codprawn · 22 June 2007, 13:19

http://www.google.co.uk/url?sa=t&ct=...XEyDin6c_f06Lg

See I don't claim to have invented the technique - it is quite widely known - even by the officials.......

Jono · 22 June 2007, 13:28

Matt's original rule applies here............

codprawn · 22 June 2007, 13:43

Quote:

Originally Posted by Jono

Matt's original rule applies here............

Do you realise that your quote of

"brakes to slow, gears to go"

comes from the Police driving handbook of 1935 - it MAY be suitable for regular driving but not when towing heavy loads.

As to it causing extra stress on engines/gearboxes etc I have yet to do so - and some of my vehicles have covered over 175,000 miles. Difference is I don't have to change brake pads very often!!!

Jono · 22 June 2007, 13:56

Try "Googling" a bit harder... you may come across sites like IAM or the like... and we're talking about modern Light vehicle not modern LGV's who have the luxury of Ex. gas brakes or EM retarders for long descents...

Damn! Damn... Matt? Sorry it's too late the force is too strong..

codprawn · 22 June 2007, 14:18

Quote:

Originally Posted by Jono

Try "Googling" a bit harder... you may come across sites like IAM or the like... and we're talking about modern Light vehicle not modern LGV's who have the luxury of Ex. gas brakes or EM retarders for long descents...

Damn! Damn... Matt? Sorry it's too late the force is too strong..

I know IAM teach that method - they also teach a load of other crap!!! I know several IAMs - they are usually boring Volvo drivers or caravanners.

You mention the exhaust gas brakes - do you realise they do the same thing but are the preffered option because they aren't so noisy?

"Compression braking, a form of engine brake, produces extreme amounts of noise pollution in comparison to exhaust brakes. For this reason, some vehicle original equipment manufacturers prefer to use exhaust brakes, even when the performance is not as good, just because of the noise issues. This is particularly common for delivery vehicles."

Jono · 22 June 2007, 14:40

You're right Codders. You win.. how can we mere mortals who only have our limited experience of the real world ever hope to win an argument with a Sage of your vast years and extensive motoring experience....

codprawn · 22 June 2007, 14:53

Quote:

Originally Posted by Jono

You're right Codders. You win.. how can we mere mortals who only have our limited experience of the real world ever hope to win an argument with a Sage of your vast years and extensive motoring experience....

At last you have realised..........

Rogue Wave · 22 June 2007, 15:33

Quote:

Originally Posted by jwalker

Yer, right. So you find yourself going down a brae towards a busy main road with 5½tons of rig, you apply the brakes normally to find the trailer brakes inoperative. Are you suggesting you'd stick your Disco into 2nd gear and expect that wee diesel engine to stop you?

)

I done it and it didn't work,,, fkkd the disco, and the trailer and I wound up looking the wrong way down the M5. Also the wee disco engine proved to be rather puny

Rogue Wave · 22 June 2007, 15:35

Quote:

Originally Posted by jwalker

Yer, right. So you find yourself going down a brae towards a busy main road with 5½tons of rig, you apply the brakes normally to find the trailer brakes inoperative. Are you suggesting you'd stick your Disco into 2nd gear and expect that wee diesel engine to stop you?

)

I done it and it didn't work,,, fkkd the disco, and the trailer and I wound up looking the wrong way down the M5 with an artic coming on to me. Also the wee disco engine proved to be rather puny. Fortunately I don't panic easily so my bundies survived