A (probably daft) question on starting a car

[Mike335i]

Absolutely clutch pedal down when starting, partly as it won't start without it, but no risk of lurching.

[LarsG]

JustALooseScrew said:

Manual car, gear selection is in neutral.

Should/do you put your foot down on the clutch pedal or leave it completely off it when you start the engine?

My answer: I do press the pedal.

Though really thinking about it now I'm struggling to come up with any valid reasons for this 'habit'.

Being over 50yrs old, and remembering back to the old days where removing any load what so ever on the engine was like winning a bonus ball in getting the car/bike to start.

Thoughts?



I would have preferred to start a poll thread, but 'newbies am not allowed'

Wife's car has auto start and won't start unless the clutch is depressed when starting it.

[Peter3442]

One reason for not depressing the clutch is to avoid load on the crankshaft thrust bearing when it's likely to be dry of oil.

[Wacky Racer]

Biggles delivers the goods said:

Always have clutch depressed when I start, was taught that way by my old man. It's good practice, for safety if nothing else.

This.

[JustALooseScrew]

Peter3442 said:

One reason for not depressing the clutch is to avoid load on the crankshaft thrust bearing when it's likely to be dry of oil.

Were you reading this thread too?

[Pica-Pica]

Peter3442 said:

One reason for not depressing the clutch is to avoid load on the crankshaft thrust bearing when it's likely to be dry of oil.

Never had a failure of that type on last two cars, each reaching 150k and always started with clutch down.

[Spitfire2]

Peter3442 said:

One reason for not depressing the clutch is to avoid load on the crankshaft thrust bearing when it's likely to be dry of oil.

Definitely the case for some. The Triumph engines in Spitfire, Herald etc, especially the 1500, we're quite prone to thrust washers dropping into the sump. I never start my Spitfire with clutch down. But all my more modern cars in the last 10 years have insisted on it. Can't see it mattering on a new car

[Peter3442]

That's a lot of reaction!

JustALooseScrew
- No I hadn't seen the other thread, but it's an interesting one

Pica-Pica and Spitfire2
- I'd hope that modern crankshaft thrust bearings would have a very long life. Older ones will depend on the original design, materials and the quality of grinding of the end of the crankshaft.

[Ransoman]

Pica-Pica said:

So how does a Maserati engine cope when changing gear?

Well, And I am not expert on this matter so please forgive me if i am completely wrong, but I think... the starter motor isn't cranking the engine over while you are changing gear.

[Peter3442]

... 'end' should have been 'flat faces' as these bearings may be located around any main bearing. The cylindrical surfaces of the crank are easy to grind, but flat faces (at right angles to the main axis) are difficult. In addition, keeping these flat bearings lubricated is more difficult.

For the Maserati, once the engine is running, it should be delivering oil to the bearing so it's protected when you change gear.

Concerning thrust bearing failure, I wonder if it might be missed. That is, metal from it goes into the oil, gets pumped around the engine and destroys something else.

[GT6k]

Ditto on the Triumph thrust bearings, the 1500 was the worst but the 2 litre engine was little better. For the Spitfire and the Maserati (there's a comparison you don't make often) there is no problem once the engine is running as the bearings are no longer dry.

For modern cars on synthetic oil it probably doesn't matter but things with big gearboxes (tractors) or poor starters (classic Minis) the drag can be significant on a cold morning.

[lyonspride]

On Toyota's you have to dip the clutch to start.....

I don't want to get in on the mechanical debates, there are pros and cons, BUT the reason manufacturers implement this is to reduce the number of incidents where people claim their car "shot forward" and want to sue the manufacturer for their own stupidity.

[TwistingMyMelon]

Ive always checked its in neutral and clutch down

Just habit with a fail over to stop car jumping forward should it be left in gear

I have to start my current car with clutch depressed.

[2 sMoKiN bArReLs]

As said above, I always select neutral & depress the clutch.

Am I dreaming it...but did some Saabs in the 80s require the car to be in reverse with the clutch down to start?

[RobM77]

OverSteery said:

unless it's an american car, as they won't engage the starter motor unless the clutch is depressed.

lyonspride said:

On Toyota's you have to dip the clutch to start.....

I don't want to get in on the mechanical debates, there are pros and cons, BUT the reason manufacturers implement this is to reduce the number of incidents where people claim their car "shot forward" and want to sue the manufacturer for their own stupidity.

To this you can add Honda and BMW - neither of our road cars at home will start unless the clutch is depressed.

[watchnut]

OP is correct in starting the car with clutch down....even now, many new manual cars will not start unless clutch is depressed

Always make sure in neutral first (Safety)

best in this colder weather to make sure lights are off, wipers are off, fan off (A/C) off radio off, so if you have a battery that is low on juice all the power is going to start car rather than other stuff....it is likely to start..... then put everything else on should be part of your cockpit drill on switching off, and before starting again

When the battery on my Mini started to fail the first thing I noticed was that the start/stop stopped working (that battery lasted 6 years and about 132,000 miles of being a learner car)...so happy enough with that life span on a start/stop car

[IT1GTR]

Have always started cars with the clutch down. (My previous BMW would not allow you to start it without clutch depressed)


Tend to do this for a few reasons:
1. Always tend to leave them in gear when parked incase handbrake fails. (If I dip clutch and the car starts to roll then handbrake isn't working)
2. Less load on starter / engine (just how I was taught, rightly or wrongly)
3. Paranoia, especially in an unfamiliar car that it could still be in gear

[RedWhiteMonkey]

I can’t think of any car I’ve driven in the last few years that didn’t require you to depress the clutch when starting the engine. Pretty much all manufacturers seem to have this now. I still waggle the gear lever in neutral though, as I was told to do so many years ago when I was taught to drive.

[Dr Mike Oxgreen]

2 sMoKiN bArReLs said:

Am I dreaming it...but did some Saabs in the 80s require the car to be in reverse with the clutch down to start?

You might be thinking of the interlock between the ignition and the gear lever (which of course are next to each other).

When you park up, you can’t remove the key unless you put the gearbox in reverse. Then, when you remove the key the gearbox is locked in reverse. I guess it gives thieves an extra problem to solve.

When you start up, you can only take it out of reverse by inserting the key and turning - but you dont have to turn it all the way.

So on my 2006 9-5 I put my foot down on the clutch, put the key in and turn the ignition on, take the gear lever out of reverse and then start the engine. I think Saabs have been like that for donkey’s years. I don’t think it requires the clutch to be down, but I always do that anyway.

[yellowjack]

Scabutz said:

Never put the clutch down. If an engine won't start with the additinal load of spinning a couple of shafts in a gearbox it must be in a pretty poor state.

Probably was different 50 years ago but I've never done it in the last 20.

I ALWAYS push the clutch pedal fully down...



...because if I don't, no amount of pressing the "Power" button on the dash will start the car. All you get is some daft message in the dash display saying "Press clutch to start".

This is my first car where I've needed to do this but after six years of ownership, I suppose it's probably become an ingrained habit now. not that I imagine it'll do any harm to a car that doesn't need it.

It can be a pain, though, if you want to start the car on the drive to have a look under the bonnet with the engine running. Got to get at least one leg in as far as the clutch pedal to do so, not a simple turn of a key like the olden days. I assume it's a safety device to prevent inadvertent starting by youngsters "playing driving" in dad's car, or accidentally putting your hand on the starter button while cleaning the interior with the remote fob in your pocket...