[Petrolhead_97]

Does anybody know how a car bump or push starts? If there had been too much of resistance when the engine is turned off and the car is in gear, how does pushing a car to gain momentum and transfer that to the engine by engaging the clutch pedal works?

I think the engine should turn over, or spin to a certain RPM after which due to the supplied mixture and ignition, combustion starts and the engine runs under its own power.

The car push starts in 1st, also does it in second.(even in modern push start stop systems, I have the experience) If the engine had enough resistance that it would not turn over in 1st at all, how does it turn over and start?

[Rehaan]

Originally Posted by Petrolhead_97

i.e, the slope is on the steeper side, as it leads to my basement parking.

I tried with an older WagonR on it,(with 1 lakh+ kms on it) it has the same behaviour.

Yeah... it looks like this is just a bit too steep.

Few options:

1) Park somewhere else

2) Have your hand-brake adjusted so that it engages better

3) If you have a kerb (ie. even a 1 foot wide raised 'sidewalk') on the slope, turn your wheels accordingly (What is the correct way to park on an incline?)

4) Have some sort of fixed chocks or "bumps" installed, even if just behind one wheel (closer to the wall). Even a plastic road-hump might provide enough resistance to keep your car in place:

Originally Posted by Petrolhead_97

Does anybody know how a car bump or push starts?

To do that in petrol cars, you need a spark + fuel.

- In carbureted cars, you might get fuel but you won't get spark unless the ignition is active.

- In MPFI cars, you won't get either unless the ignition is active.


For push-starting a car, the ignition needs to be active (ie. the last possible position of the key turn where it stays put).
This will not be the case for a parked car.

[sach.sri]

Originally Posted by Petrolhead_97

Sorry, I might have a bad judgement, it is moderately steep slope, i.e, the slope is on the steeper side, as it leads to my basement parking.

https://Youtu.be/kNgZKRN5fXc

I learned diriving on my dad's premier padmini. And things that were drilled into me for parking were
- handbrake is not reliable - i think it was cable operated and used to breakdown even when pulled too much.
- always park in gear (reverse / 1st gear) depending on the car direction and slope, etc
- always put small pieces of rock / bricks (depending on availability) on the all the tyres when parking on slopes to prevent roll down.

i guess - put "ot" (try pronouncing this in hindi) when parking on slopes

[SS-Traveller]

Originally Posted by Petrolhead_97

I tried with an older WagonR on it,(with 1 lakh+ kms on it) it has the same behaviour.

Considering The 2022 Ertiga to be fairly new, with barely 7500kms on it, do I need to be concerned?

No concern at all.

Originally Posted by Petrolhead_97

To secure the car, I need to pull on the handbrake really tight, like almost in the vertical position, such that the brakes don't skid.

The trick to engage the handbrake well enough to hold most cars firmly on a steep slope is...
1. Keep the engine running (idling);
2. Press down the brake pedal hard;
3. Pull up the handbrake lever all the way that you can, keeping the release button depressed;
4. Once the handbrake lever locks into the highest position you can pull it up to, release foot brake, switch off engine;
5. Wait for a few seconds to see if the car creeps away from its position - it should not.

Once this is done, disengaging the handbrake will not be easy, unless you reverse the process...
1. Start the engine, let it idle;
2. Press the brake pedal with all your might;
3. Pull up the handbrake lever while pushing in the release button;
4. Release (push down) the handbrake lever;
5. Be careful about releasing the foot brake, or your car will roll away.

[Petrolhead_97]

Originally Posted by Rehaan

Yeah... it looks like this is just a bit too steep.

Few options:

1) Park somewhere else

2) Have your hand-brake adjusted so that it engages better

3) If you have a kerb (ie. even a 1 foot wide raised 'sidewalk') on the slope, turn your wheels accordingly (What is the correct way to park on an incline?)

4) Have some sort of fixed chocks or "bumps" installed, even if just behind one wheel (closer to the wall).

Thanks a lot. I had thought that a manual car would be impossible to move if parked in gear. As if it is similar to parking an Automatic in Park mode.

Recently I had to park on the ramp, after some experimenting, I noticed that parking it in 1st/Reverse and pulling the parking brake really tight (like a single rep of a bicep workout) , the car feels secure.

i.e both the gear and the parking brake combination secured the car, and only one of them didn't. If I am only using the parking brake, the brakes seem to slip, and do not lock the wheels properly.

I tried jerking the car, tried pushing it from behind, but it doesn't seem to move, also the rear brakes don't slip, and they lock the wheels.

For extra precautionary steps I might be buying chocks, and I am parking towards/away from the kerb accordingly.

[Gansan]

Originally Posted by Petrolhead_97

Is this normal?

It is normal with a steep enough slope. In such cases we should leave the car in reverse gear and with hand brake on. It will be safe to leave the car in first gear without hand brake only when the ground is level.

[Petrolhead_97]

Originally Posted by SS-Traveller

No concern at all.

The trick to engage the handbrake well enough to hold most cars firmly on a steep slope is...

Thanks for the advice. Shall I have any problems with the releasing of the rear drum-brakes, while driving off? I fear if they get locked .

I had been planning a drive to Darjeeling (a hill station) with my car, and the roads are pretty steep during the climb, specially at the hairpin bends. It is like a Petrol would struggle in 3rd gear, and most of the times it would be either in 1st or 2nd, and some of the slopes are only negotiable in 1st.

Last year I had a cab ride to my hotel in Darjeeling, and the hotel is situated almost 200-300 ft. above the city of Darjeeling. A very steep road with multiple turns and hairpin bends makes you climb to that elevation in a very short distance. Walking (better call it trekking:-) ) would be a bad option for many, if they don't sport a healthy heart. Cab drivers charge almost 300Rs INR to transport you to and from the mall road and the summit hotel.

Also its a double-way road, and if you need to slow down during the climb, or stop, losing all the momentum, then picking it up the slope, would mostly result in the tyres wheelspinning, and skidding away to glory, and with the car rolling back the slope

I have seen the locals parking their cars on that road using a combination of both, but they don't steer their cars to the kerb, probably they are overconfident about their cars secured.


Could you advise me on the precautionary steps to park on such roads, if I am successful in executing my plan?

[Petrolhead_97]

Originally Posted by Rehaan

Yeah... it looks like this is just a bit too steep.

I tried to park the WagonR on the upward incline, i.e the starting of the ramp (from my basement parking in my apartment complex), with the gear selector slotted into Reverse.

I observed the slope'cranking'the engine in the opposite direction, by looking at the rotation of crank pulley.

Please have a look, and share your valuable opinion:

https://youtu.be/glQfnfzv2ms

[Petrolhead_97]

Originally Posted by dhanushs

Well, the K15 engine has a decent compression ratio

I'm guessing this has something to do with tech that makes the engine more efficient.

Yeah I just now read the article on the Maruti Suzuki website about the engine. It says they have used rockerless camshaft setup, low tension piston rings, which results in lesser Friction between the cylinder walls and the piston, and a lot of tech to make the engine efficient. I don't think the engine has a problem because my car is fairly new, 7.5K kms barely and 1 yr 5 months old.

Also it is the largest in the K-series lineup, and has a lot of tech behind the development of the engine, in 2018 I guess.

I also saw a forum here, where someone's new Embera CRDI with a 2.0l diesel had difficulties holding onto a slight slope. As it is a diesel, it should have even a higher compression ratio, and better engine braking capabilities.


What are your opinions about this?

[Joe367]

Originally Posted by condor

I guess this is why people suggest to use the gear opposite of the slope direction in order to aid parking on slopes.

Will that put stress on the gearbox and cause any damage - using the opposite gear to park?
I have always parked in the gear same direction as slope
- only as a precautionary measure incase handbrake fails.

[condor]

Originally Posted by Joe367

Will that put stress on the gearbox and cause any damage - using the opposite gear to park? .

And exactly that is my concern, and had posted accordingly here above.. Hoping the experts chip in.

[svsantosh]

Originally Posted by Petrolhead_97

Suddenly while leaving the car, I noticed the car lunges forward in jerks, and stops again, before lunging forward again with a jerk, covering inches/ or a few cms continuously.

So you are in MANUAL Car, and approaching a UP or DOWN Slope...

For UpWard Slope

1) Come to full stop on brakes (car engine on still)

2) When Vehicle is Running, and 1st Gear engaged (Clutch & Brake Fully Pressed, NO HAND BRAKE yet) turn key off

3) Release CLUTCH pedal first, car will not move because you are On Brake pedal press mode still (No hand brake yet)

4) Now release BRAKE pedal gradually - You will see car move backwards down the slope a few inches, the gear shaft has to rotate in sync with the dead crank and find its dead spot - can be a few inches movement, no hand brake yet. The Suspension spring opening up can cause creaks and moans - its OK!

5) Now the engine is holding the driven wheels with its compression vacuum - Now Engage Hand brake with good arm power.

Car will never move now.

Note - If car facing downward slope

All steps same except (2) Engage Reverse Gear

---------------------
For AMT Cars similar story - Turn key off in WHILE in D or R mode

My wife's minor accident and lessons
https://www.team-bhp.com/forum/road-...t-neutral.html (Parking AMT cars in D / R and not Neutral)

--------------------
For Automatic

1) Into P (park mode) first (let the trans lock the wheels)
2) Yank the hand brake hard enough

If you dont engage hand brake properly and if you are in the direction of slope --> gear, the car will roll and piston move up and down. NOTE all the cylinders are not holding a dead car, its usually 50% fully closed and 50% open (depends on timing cycle). A turned off engine never has all 4 pistons or valves in same condition. Hence only few cylinders hold the car and it can try to rotate and move the car.

Originally Posted by condor

And exactly that is my concern, and had posted accordingly here above.. Hoping the experts chip in.

Hi Condor - Nothing will happen if the engine vacuum holds the dead weight of a car. It goes through 1000+ times higher stress under WOT and driving conditions.

[condor]

Originally Posted by svsantosh

Hi Condor - Nothing will happen if the engine vacuum holds the dead weight of a car. It goes through 1000+ times higher stress under WOT and driving conditions.

Normal conditions - the slope and vehicle movement direction are the same. Here we are talking of opposite directions. May be a millionth part of like engaging reverse when actually in forward direction ? I mean - something like that ?

[svsantosh]

Originally Posted by condor

Normal conditions - the slope and vehicle movement direction are the same. Here we are talking of opposite directions. May be a millionth part of like engaging reverse when actually in forward direction ? I mean - something like that ?

Ok Got your point, I think we can safely rule that point out when car is in ZERO Speed. At zero speed nothing inside the GB is moving, the main shaft and counter shaft included.

The only reason the Krrrrrr noise comes when engaging R when car is moving forward (or vice versa) is because the main shaft and counter shaft are spinning in opposite directions and the teeth tip of the R gear (say for example) is engaging in the opposite direction. The gear tip would try to chew other away. If they did engage fully, teeth face to teeth face, it will be catastrophe inside the GB in an instant.

[Petrolhead_97]

Originally Posted by svsantosh

If you dont engage hand brake properly and if you are in the direction of slope --> gear, the car will roll and piston move up and down. NOTE all the cylinders are not holding a dead car, its usually 50% fully closed and 50% open (depends on timing cycle). A turned off engine never has all 4 pistons or valves in same condition. Hence only few cylinders hold the car and it can try to rotate and move the car.

Does that happen for both manuals and automatic?

I knew Automatics lock the shaft with a parking pawl which locks the drivetrain from any sort of rotation, but depending on it could stress it, I believe.

What about Manuals?