 | Home > Technical > Puma 2.2 engine break |
 
|
|
|
| ericvv Member Since: 02 Jun 2011 Location: Near the Jet d'Eau Posts: 5816   
|
Interesting explanation blackwolf. A bit
 but that brings me to a question I posed myself many times about what kind of additional brakes our city buses use. I know when they brake down, especially at a downhill slope, that there is something that very seriously helps their regular brakes. You hear the engine pick up rpm and the speed reduction then can be quite serious. It surely is not this Jake brake system, as there is no noise as you describe, and I cannot imagine that they have an exhaust brake either if as you say it is not very good for the engine. Those buses all run around 100/150.000KM per annum, and their total lifespan KM runs to well over 1.5 to 2.0MLN.
Eric You never actually own a Defender. You merely look after it for the next generation. http://youtu.be/yVRlSsJwD0o https://youtu.be/vmPr3oTHndg https://www.youtube.com/watch?v=_GtzTT9Pdl0 https://www.youtube.com/watch?v=ABqKPz28e6A https://www.youtube.com/watch?v=rLZ49Jce_n0 https://www.youtube.com/watch?v=XvAsz_ilQYU https://www.youtube.com/watch?v=K8tMHiX9lSw https://m.youtube.com/watch?v=dxwjPuHIV7I https://vimeo.com/201482507 https://www.youtube.com/watch?v=ZSixqL0iyHw |
||
27th Sep 2016 11:23am |
|
| Ramsay Member Since: 30 Sep 2015 Location: Moffat, Dumfries & Galloway Posts: 627  
|
Buses will be fitted with clever transmissions that include a braking effect. See for example
http://www.voith.com/en/products-services/...-9943.html[/url] 1995 Defender 110 CSW 1971 SIIA Lightweight |
||
|
27th Sep 2016 12:08pm |
|
| shaggydog Member Since: 12 Aug 2012 Location: Kent Posts: 3347  
|
Good Video showing difference a Jake brake can make.
Now please excuse me I need to change.......Job, Country I live in etc.... Running Restoration Thread http://www.defender2.net/forum/post323197.html#323197 Self confessed mileage hunter  |
||
|
27th Sep 2016 4:47pm |
|
| derbywill Member Since: 25 Mar 2010 Location: Derbyshire Posts: 559  
|
A jake brake is just a brand name of a certain type of engine brake, they are available over here been fitted on Cummins engine trucks for a long time, also they are fitted to the Mercedes OM471 engine plus various others. But most noise they make is suppressed by the catalytic converter and DPF.
An engine brake generally alters valve timing and some fitted with a variable geometry turbo will put the turbo to full boost to increase the amount of air in the cylinders to make it harder to compress the air thus creating more engine retardation. An intarder is basically a large hydraulic pump on the back of the gearbox it is generally used in conjunction with the engine brake creating a lot more braking effort. Kind Regards Will 2005 90 XS 1954 86'' Series 1 tilt 1968 88” 2A 200tdi 2002 110 Hardtop |
||
|
27th Sep 2016 8:35pm |
|
| Gonarezhou Member Since: 08 Mar 2015 Location: White River Posts: 178  
|
Just disconnect the anti-stall on the gearbox and you will be able to use low range without the vehicle running away from you!
|
||
|
6th Oct 2016 8:26am |
|
| Naks Member Since: 27 Jan 2009 Location: Stellenbosch, ZA Posts: 2645 
|
jah, not sure that this is a good idea...
I've never found the vehicle running away in low range, esp 1st low. -- 2010 Defender Puma 90 + BAS remap + Alive IC + Slickshift + Ashcroft ATB rear 2015 Range Rover Sport V8 Supercharged 
Defender Puma Workshop Manual: https://bit.ly/2zZ1en9 Discovery 4 Workshop Manual: https://bit.ly/2zXrtKO Range Rover/Sport L320/L322/L494 Workshop Manual: https://bit.ly/2zc58JQ |
||
|
6th Oct 2016 8:31am |
|
| blackwolf Member Since: 03 Nov 2009 Location: South West England Posts: 17443 
|
Anti-stall has no connection whatsoever with the gearbox. Perhaps you're thinking of idle jack. |
||
|
6th Oct 2016 8:40am |
|
| Gonarezhou Member Since: 08 Mar 2015 Location: White River Posts: 178
|
"Anti-stall has no connection whatsoever with the gearbox.
Perhaps you're thinking of idle jack." I stand corrected....I thought that the increased idle when engaging low range was connected to anti-stall. But I think this is a problem as there are several circumstances when you do not want the increased idle speed in low range. This can be when you are gently grinding your way over obstacles, on a flat or incline and more importantly on a decline especially when the surface is unstable. The increased idle speed works against you (by not) using the engine and gearing as a brake instead of the driver applying the foot brake. I don't like the system and I know of others that have disconnected the system for this reason. There is a You Tube video of a comparison between the Defender (Puma) and a 70 series Land Cruiser that highlights this problem. In my opinion it is a pity that there is not a switch to engage or disengage this feature just as there should be a switch for traction control. In deep sand TC can work against you! |
||
|
6th Oct 2016 9:56pm |
|
| Penguin Member Since: 08 Dec 2014 Location: Tienen Posts: 247  
|
there a TC off/on switch on our 2.2 28/02 - Loss of a good friend...
In a time of chimpanzees, I was a penguin. |
||
|
7th Oct 2016 5:38am |
|
| macfrank Member Since: 05 Nov 2015 Location: somewhere in the north Posts: 1081  
|
That switch is for DSC, isn't it? TC can be disabled by removing a fuse, but I think that also disables ABS.
|
||
|
9th Nov 2016 11:00pm |
|
|
|
| All times are GMT |
< Previous Topic | Next Topic > |
Posting Rules
|
Site Copyright © 2006-2024 Futuranet Ltd & Martin Lewis
