Clutch pedal when starting car

TadleyBaggie

vikingaero wrote: »

Most manual cars with starter buttons require clutch down before they will start.

Although my Megane CC will start without the clutch being pressed if the car is in neutral. You still have to press on the foot brake however.

Joe_Horner

Parva wrote: »

So, thrust bearings are soft metal plates? And these same thrust bearings are lubricated with oil once an engine is started up? What a load of complete and utter bull. Do you even have the slightest understanding of how an engine, gearbox and clutch work?

I've got a very good understanding of how they work, thanks

The clutch is bolted to the flywheel and, when you press the pedal, the release bearing is forced against the diaphragm spring of the clutch cover and tries to push it forwards, along it's axis. Because the flywheel is attacked to the crankshaft that tries to move the crankshaft in the same direction. It's the crank thrust bearings that stop it actually moving.

The thrust bearings don't do much when the clutch isn't pressed because normal running doesn't involve any big forces "along" the crank axis. So almost all thrust bearing wear happens when the clutch is operated.

This is a crank thrust bearing, built into the side of a main bearing shell in this case (some are separate, some are made as part of the mains):


and this is the thrust face of the crank that presses against that bearing, to control crankshaft end-float:


In the above case, they're both knackered because the thrust bearing has worn through it's soft bearing surface and the steel backing has been running directly onto the crank.

Gloomendoom wrote: »

He is actually correct about how it all works, although the rest of the post is debatable. It's probably six of one and half a dozen of the other. The decision is made for you on many modern cars anyway.

I agree it's debatable whether it's a problem or not in any particular case. I'd certainly hope that manufacturers who're including clutch over-rides for the starter are making sure they're designed the rest to cope. But it is a factor to keep in mind, especially for people running "uprated" clutches that tend to have heavier springing than the manufacturer intended.

Personally, I do both from time to time and I've never yet started in gear and driven into anything. I would have thought that an over-ride to make you start in neutral would make more sense but then it would force you to do what your driving instructor taught you if you stall at lights

atrixblue.-MFR-.

Gloomendoom wrote: »

My Land Rover must be one of the exceptions.

Mrs G's Kia needs the clutch pedal depressed. Not a problem as, like many on here, it's something we do anyway.

in the kia manual it reccomends depressed clutch before starting!.

but you can start them without dads cee'd dont need to be depressed 58plate. dont know about picanto's ect.

peter_the_piper

That'll take some getting used to if I buy a new car. I've always left car parked in gear and started in neutral, habit really

clangnuts

thefishdude wrote: »

i allways press clucth but thats because i allways park and leave my car in gear, i was taught that way and my dad also does park in gear so them together and its ingrained in my soul. the only vechile i dont is the works 7.5tonne truck cause it wont start in gear it lock out the ignition even with clutch down.

If you park in gear without good reason, and your car is hit while parked, then there's a good chance the gearbox will be wrecked, and the car could be written off.

pulliptears

Must be all Chryslers as our old PT Cruiser had to have the clutch pressed to start. Shame my OH didn't tell me about it and left me scratching my head for some time when we first had it.

Obukit

clangnuts wrote: »

If you park in gear without good reason, and your car is hit while parked, then there's a good chance the gearbox will be wrecked, and the car could be written off.

No it wouldn't, it's like jump starting it except the engine won't start. Not great if you did it every day but it won't wreck your gearbox unless it's on it's last legs.

clangnuts

Obukit wrote: »

No it wouldn't, it's like jump starting it except the engine won't start. Not great if you did it every day but it won't wreck your gearbox unless it's on it's last legs.

So if your car was in reverse, and someone slammed into the back of you, it wouldn't cause any damage to the gearbox? (or in forward gear and someone hit the front?)

I know it's a small risk, but I know of it happening to a works vehicle some years ago. Drunk driver hit the back of the parked minibus doing about 25mph. The gearbox was wrecked and beyond repair.

peter_the_piper

Well I must have been lucky as nothing has happened in the last 45 years of driving wheras it did save the car when the handbrake cable failed on a hill.

clangnuts

peter_the_piper wrote: »

Well I must have been lucky as nothing has happened in the last 45 years of driving wheras it did save the car when the handbrake cable failed on a hill.

I would still park in gear if I was on a hill. I just don't do it, if there's no reason to.:D