Push Start a Car




Push starting, also known as "bump starting" a car or motorcycle is a way of getting the vehicle started when either your starter motor or battery have given up the ghost. It consists of getting a vehicle into it's running state, pushing it to get some momentum, and engaging the transmission, to start the engine spinning. Be aware that to push start a car you need to have a manual transmission, and trying to push start an automatic vehicle will either fail to start it, or possibly damage the transmission. You should also avoid bump starting a vehicle with a catalytic converter as unburned fuel mixture in the exhaust may cause it harm. It can still be done in a pinch though. Though it may be tempting if you're alone and on a hill, it's a really bad idea to push the car down the hill then jump in to bump start. People have accidentally run themselves over trying this. It's best to find someone to help.

Step 1: Getting to a Running State

The first step in push starting a car is getting it in a state where it's ready to run. This usually just means disengaging the parking brake, having the key in the on or running position, and having the driver in place. This makes it so once the momentum of the pusher(s) is transfered to the engine it will be ready to use that momentum to start up and run.

Step 2: Push Like Heck

Now you've got the car ready, the driver in place, at least one person ready to push, and preferably a downhill slope. It's time to push.

Put the car in second gear (possibly higher depending on how fast you're rolling when you engage, press in the clutch pedal, and push the car until you get as much speed going as possible. It's best to have a long stretch to go down and nothing to worry about running into, but depending on how many pushers you have and how light the car is you can get away with some fairly short runs. Just remember that the more momentum you can build up the more likely your bump start will be successful.

Step 3: Use Your Momentum to Start the Engine

Now that you're rolling at a good clip, your pushers should let the car roll on, and the driver should engage the transmission. You should engage in 2nd gear, since engaging into 1st gear would winf up the engine's RPMs fast enough that it may cause damage. I've also seen people starting by push starting in reverse and engaging in reverse, though 2nd gear pushing forward is still your best bet. The idea is that whatever speed the car is going in, you should engage the engine in the gear that you would normally operate the car in at that speed.

Make sure to give it some gas as you engage or you'll likely stall the engine out. If it stalls anyway try again and see if you can get a couple more people to help push. Make sure you figure out what's causing your starting problem ASAP so you won't be push starting any more. As mentioned in the intro, you can also push start any motorcycle with a clutched transmission. This is very useful since motorcycle batteries carry less charge and they're usually small enough for the driver to push and engage the motor themselves. Pictured below is an old board track bike which was designed needing a push start every time because it's stripped down to save weight. Happy trails.

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    39 Discussions


    4 months ago on Introduction

    But what I want to know is what kind of ignition is happening with this bump start !?!? Is it compression ignition or do you need the starter to spark still ?

    2 replies

    Reply 2 years ago

    do it in first, if you do it in second you need to run faster to get the same rotational transfer to the engine - too much power you must be joking there is a reason they judder when they start - if its too much power as in acceleration then your driver needs to learn to bump because they obviously have the accelerator on the floor if it takes off on them,-- a little throttle, hover a foot over the clutch and be ready to slam the anchors on with your right foot once it actually starts


    Reply 2 years ago

    I agree, 1st gear, unless you're going fast down a big hill or getting a tow and you've gained some speed. I'm a dab-hand at it since I had a dodgy battery for a long time. I've often got a car running within 4-5 feet, especially when there's a wall in front of the car!

    i don't think an auto (not running) could build enough tranny pressure to lock-up a torque converter at any speed... I could be wrong though.


    Reply 8 years ago on Introduction

    me and my family did manage to push start a Toyota Lucida Van once. But that was on a steep slope and the car was going approx 30kph when it started


    Reply 8 years ago on Introduction

    So you could probably do it with most auto transmissions if you pushed the car up to speed with another car. Good to know.


    Reply 4 years ago on Introduction

    Yes, automatic works also. I've done it for 3 months and drove my car daily. Worked perfectly.


    6 years ago on Introduction

    i learnt this trick a while back, as the clutch is released turn the the key at the same time if there is any any residual charge in the battery it will provide assistance, i would not attempt push starting a car without turning the key at the same time, it will improve your rate of success, unless the battery is complely flat.


    7 years ago on Introduction

    This works for motorcycles, tried and tested In a bike you don't do it any differently... except probably the gear. Many a bike won't let you put 2nd gear very easily unless you're rolling at some speed, so probably you should stick with 1st gear. So you put it on either 1st or 2nd, hold the clutch, gain enough momentum, release the clutch and give it some gas.

    But watch out! you should do it like in the third step's pic, so get a couple of friends to help you. If you try doing it by yourself you can loose control of the bike too easily when the engine starts.

    Of course, if you have a kickstarter you shouldn't be trying to push! ;)


    9 years ago on Introduction

    To get the car moving from a dead-stop, I would suggest (especially on bigger/heavier vehicles) that the pusher CAREFULLY push forward on the top part of the REAR tire... This gives the pusher some added leverage; similar to taking off in 1st instead of 5th... larger diameter gears allows for easier take-off. Pushing the car's bumper while sitting still will prove to be like taking off in 5th compared to pushing on the tire. ONCE THE CAR IS MOVING, the pusher should then step back and utilize the bumper, trunk, or A-pillar as this will be safer when the vehicle's speed increases... plus, the tire will end up moving faster than your hand can push. Good luck, and safety first :)!