Tick Over Speed

[8953lewis]

Hi All

 

Can anyone tell me what rpm should my 2.8crd auto be ticking over at?

 

on start up my gv ticks over at about 850rpm, put it in gear & revs still stay at about 850rpm to me this seems high as car wants to pull away & if you let it go on tick over i get upto about 10mph without touching the throttle.

I thought it should be somewhere around 750rpm.

 

If so can you tell me where the adjustment screw is to lower the rpm.

Many thanks.

 

[Stevec0268]

My 2005 2.8 CRD also ticks over at around 850-900

[Dazandtrace]

Hi my 2006 crd is the same seems normal to me

[QinteQ]

put it in gear & revs still stay at about 850rpm, car wants to pull away without touching the throttle

Is exactly what its supposed to do my friend, lots of reasons, including a hill start.

[8953lewis]

Thank you all for your replies can't you tell I have never had an automatic before.

 

Mark

[QinteQ]

Thank you all for your replies can't you tell I have never had an automatic before.

 

Mark

Yep certainly can, I've had em off and on since the 60's, but I am always aware that a forum is a 2 way COMMS and while I've prolly done close to 9,000,000 miles in that lifetime I learn things every day on forums so never be afraid to ask.

[nigelhobbs]

I was wondering about this as well my grande voyager is also keen to move off I'm trying to get in the habit of moving it to park when at the lights I had a mishap with it and relaxed on the brake pedal and shunted a smart for 2 of all things OOPS Z!

To add to the problem the park brake is next to useless. It just holds in neutral but in drive or reverse it lets the car move I've been trying to improve the park brake for weeks Tried new shoes new cables and the brakes are fully adjusted

Just to try I faced the car up hill on a very steep hill pulled the hand brake to max then in neutral she rolled back about 2 ft and then held. I put her in drive and she started to go uphill forward I've not found an auto do this before but. I don't think there is a way to lover the idle speed its controlled electronically I'm just experimenting with an electric park brake I need to make some brackets and cables will update here when I have any results

[QinteQ]

I was wondering about this as well my grande voyager is also keen to move off I'm trying to get in the habit of moving it to park when at the lights I had a mishap with it and relaxed on the brake pedal and shunted a smart for 2 of all things OOPS Z!

To add to the problem the park brake is next to useless. It just holds in neutral but in drive or reverse it lets the car move I've been trying to improve the park brake for weeks Tried new shoes new cables and the brakes are fully adjusted

Just to try I faced the car up hill on a very steep hill pulled the hand brake to max then in neutral she rolled back about 2 ft and then held. I put her in drive and she started to go uphill forward I've not found an auto do this before but. I don't think there is a way to lover the idle speed its controlled electronically I'm just experimenting with an electric park brake I need to make some brackets and cables will update here when I have any results

Park brakes are for parking as in engine off and gear-locked transmission and originally designed 60 or so years ago for a long fulcrum American foot-lever applied brake lever. our short lever degree of 'arm pull' arc is never going to equate to the degree of body-weight kick-on brake of the American system. The British ton is 2240Lbs and the American short-ton is 2000Lbs, this is one heck of a lump of heavy metal.

 

The vehicle only ever becomes immovable with a transmission lock. RPM sound right, its the usual mental transition people need to make who have not driven an auto, particularly one of this weight. The handrick is absolutely pathetic. From a UK point of view we tend to have grown up with a pull on brake which is exactly what this is not - its a parking brake. I live minutes from here and travel

on a weekly basis. This portion is [7.5% on the strava segment gradient] a 1 in 4 gradient, my own formative years were at the bottom of a 1 in 3. My point is in a very long lifetime I have never needed to kamikaze any road journey till the GV. Its something we all cope with but the pre-realisation that once you commit down or uphill in any gear to these types of road in our GV's ramming it into a wall is in the event of power loss your only option.

 

I never found a solution, if you apply more adjustment to the shoes they will bind, in a non-sliding shoe arrangement you could / should re-adjust after 'bedding in' for the best results after the new shoes have ground down the linings to the precise drum diameter to reduce the shoes tendency to 'grab' on the leading edge when over-adjusted on the knurled adjuster. In short the design has a bias to assist in reverse rather than forward and to allow the operator to engage or disengage a gear - hence the reason you can't even start the car without applying the footbrake in the first place. best of luck.

[nigelhobbs]

Yes it's a very bad design. I would say the drum and shoes are too small

And there is a lot of stretch in the cables and no sort of amplification of the pull on the brake lever

I was told by an mot tester that the park brake should lock the wheels up but this does not relate to the efficiency for a pass the stated limits are programmed into the brake tester to result in pass or fail on that particular vehicle .

You could consider the park brake as a sort of emergency brake think about it if your brake pedal hit the floor what would you do ? Yes try the park brake in most cases it would certainly slow you down and the inevitable impact would get reduced

On a truck the park brake is more efficient than the service brake it operates on all the wheels by using a strong spring to apply and air to hold it off if the air is evacuated the brake comes on fail safe. Hence you can often see big black skid marks finishing on the hard shoulder that's the brakes coming on when a fault happens like a broken air hose .

I was also thinking of changing the hand lever to a foot controlled brake but I'm thinking it's only possible on a left hand drive I am told the Australian voyagers are hand brakes too

[QinteQ]

The testers manual might give the figures but the bottom line is the both the parking and the road brakes are too small and always were, they have since been uprated to larger sizes in since our models were introduced.

You could consider the park brake as a sort of emergency brake

No this is the issue my friend, it is not an emergency brake at all. Its designed to lock two wheels only and only after the vehicle is already stationary and there is no wheel rotation resistance. It is not meant to be used when the car is rolling. It .. .. if that use was ever re-instated would lock up the rear wheels making the car go out of control, which is what used to happen in the olden days. Best of luck my friend.

[darkchild101]

Hi All

 

Can anyone tell me what rpm should my 2.8crd auto be ticking over at?

 

on start up my gv ticks over at about 850rpm, put it in gear & revs still stay at about 850rpm to me this seems high as car wants to pull away & if you let it go on tick over i get upto about 10mph without touching the throttle.

I thought it should be somewhere around 750rpm.

 

If so can you tell me where the adjustment screw is to lower the rpm.

Many thanks.

 

 

I have asked similar question on different forum. My 2.5CRD revs/idles at about 900rpm and to me that seems rather high. I have a Mercedes w202 2.5 turbodiesel auto and that revs at around 500rpm

[nigelhobbs]

I don't want to hi jack the posting as it were ,,, but could you give some details of the updated braking guessing the newer models have this fitted. So is it possible to modify to a better braking system legally of coarse. It alarms me the brakes are considered so poor

[Semmysonic]

Do they have hand brakes? :-D

This is my second auto last one was a 5 series BMW and I don't think I ever used the hand brake in the 3 years I owned it.

I've used it on the gv it only really when parked on a slope ( just in case). Just have to get used to sitting in traffic with your foot on the brake (which feels wrong after driving manuals)

[QinteQ]

They have a hand parking brake, not a hand emergency brake. A Pawl engages with the shift lever when its in park mode only on both column and floor-shift models and is controlled by software, hence the reason you can only engage it at stand still. The reason is .. ..  the American idea became a registered American standard that then went world wide about 60 years ago. The lousy brakes however are real on these vans for the reasons already given, but are good enough to easily pass a UK MOT. I've long preferred inboard disk park brakes although many people hate them too, as they do e-brakes.

 

 

[nigelhobbs]

I've just been reading on automatic transmissions that's the constant mesh type Not be be confused with a semi auto which is a normal H pattern manual but with an electronic power shift

The break in the drive between the engine and the transmission. Clutch if you think of it that way , is achieved by lower centrifugal forces and lower oil pressure acting on a turbine and impeller Known as a torque converter. At lower engine revs. As the revs increase and reach a threshold point the impeller will force oil to the turbine and start to allow drive to the transmission If then your revs are too high the drive will be carried through and want to move the car if you prevent it by holding the foot brake you are without doubt allowing some disagreement to ocure that has to result in wear or at least heat generated

I don't see why the manufacturer would see this as acceptable So I kinda think this high tick over speed is a severe disadvantage rather than a way to help the vehicle move off I would think an idle sped of around 650/700 is good to keep a steady tick over without too much emission problems. and won't allow the vehicle to want to move off

I've also read the system is part electronic so one would think taking the throttle pedal off the idle position would open an hydraulic valve to increase fluid pressure into the torque converter . I've done little work on these larger auto boxes but did complete a training course on the auto gearbox a long time ago so long it was at the standard triumph works in Coventry ! I've stripped and repaired about 5 boxes in my time but I would be sure it's all very different now