Got my first car - Some questions

oxygene

oxygene

oxygene

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Ok so I'm a little late to the game, having no real reason to drive until now. I am 32 in a couple of weeks and have just finished learning to drive and just got given my first car.
Its a Fiat Punto Dynamic, 10 years old, only 22,000 miles on he clock, like brand new condition, full MOT etc.
But thats enough of the specs! I'm primarily a techy not a gearhead (neither term meant as derogatory!) so I am interested in finding out more about it.
Ideally what I am looking for is an exploded view or step by step diagram of how the engine works. What makes it tick, why fuel works and other stuff doesnt. How it gets turned in to movement energy etc. Basically I've never looked at engines but now that I have one I'm curious to know its inner workings!
I've had a good google around but nothing really fits what I am looking for!
As silly as it sounds, ideally I am not looking for a video s I would like to study it at my leisure or at work!

Many thanks!
 
snips86x said:
So you're wanting to know how the internal combustion engine works?

If so, this any good
Click to expand...

This will get me started nicely! Thankee

Spunkey said:
*snip*

In fact check out the entire Engineering Explained channel, lots of great explanatory videos.
Click to expand...

I will have to check these out some other time :/

The main problem is, my Father, my Brother and my Step Father are all mechanics and car fanatics and could never figure out why I went a different path! So I would love to come up with something which shows I know what I'm talking about, and prove I could learn this stuff if I ever had the interest hehe.
 
TehBluebear said:
A very nice animation at the top of this page too: http://en.wikipedia.org/wiki/Four-stroke_engine
Click to expand...

Ahhh that makes things a lot easier!
So assuming the bottom shaft is already turning with some force:

Fuel goes in on a mechanical timer
The shaft thats turning causes this to compress.
A timed spark ignites this compressed fuel (I assume it wont ignite as well or burn as well if it isnt under as much pressure)
The force of this ignition pushes the main shaft down to turning again ad halfway through that cycle the exhaust gases are released.
So the force of the ignition causes the shaft to turn, providing the power to run the compression cycle and the other timers...

So how does it all start in the first place? I know theres something called a spark plug which has to do with ignition, but surely the above animation needs the shaft turning first to provide power to turn the shaft after?

*edit - Hehe just realized most of what I said is in the image description! Well, I like working things out myself, I retain information better that way!
 
Starter motor turns the engine until it can power itself using fuel /spark.

Starter motor runs off your battery and is only active when you turn the key all the way into the starter position

Spark plugs are what do that timed ignition.
 
bledd. said:
Starter motor turns the engine until it can power itself using fuel /spark.

Starter motor runs off your battery and is only active when you turn the key all the way into the starter position
Click to expand...

Ahh that makes sense. I always wondered about that!
People tell me the battery is charged by the car running, and the battery being dead means the car cant start. I just assumed it needed the battery for the spark plug to ignite it but if it needs the battery to run the starter motor first then that makes more sense!
 
Also what isn't in the animation and to be fair would make it look a mess, is the timing chain/belt which links the crank shaft (the bottom shaft) and the cam shaft(s). Some engines have a single cam shaft and others, like the animation, have two, the chain/belt linking them to the crank allows for them to turn and open/close the valves (inlet and exhaust) so air can come into the cylinder and leave the cylinder.

E: The alternator is driven off the crank by a belt and recharges the battery.
 
To keep the car running sweet, replace the following..

Oil
Oil filter
Air filter
Spark plugs
Fuel filter

Pollen filter (or cabin filter) replacement will keep it smelling fresh inside
 
InvaderGIR said:
Also what isn't in the animation and to be fair would make it look a mess, is the timing chain/belt which links the crank shaft (the bottom shaft) and the cam shaft(s). Some engines have a single cam shaft and others, like the animation, have two, the chain/belt linking them to the crank allows for them to turn and open/close the valves (inlet and exhaust) so air can come into the cylinder and leave the cylinder.
Click to expand...

Yeah I assumed it would all run off of the same shaft. So that crank shaft is the main one that goes in to the engine / gearbox, and the cam shaft(s) run the engine internals I'm guessing.
 
Well, to start the engine initially, (ie. when you turn the key), engines have a starter motor which uses a hefty amount of electiricty stored in your battery to give the crankshaft a spin. While this is happening, fuel and spark is being provided to 'carry on' that initial momentum and then take over. When you hear that whrwhrwhr noise when you first start up your car, that's the starter motor spinning up the crankshaft.

And yeah, the camshafts (the timers that you refer to) that open and close the valves responsible for intake and evacuation of gasses are driven from the crankshaft via a belt or chain, usually at a 1:2 ratio. So for every 2 full rotations of the crankshaft, the cams turn once, which is where we get the four strokes from.

EDIT: 4 posts made explaining the above while I typed that, damn it :D
 
bledd. said:
Battery also creates that spark
Click to expand...

Yes and no. Battery provides the initial charge but it's generally boosted by a coil and the timing of when the spark goes to each cylinder is either ECU controlled (multiple coil packs, one per cylinder) or distributor controlled (single coil).


oxygene said:
Yeah I assumed it would all run off of the same shaft. So that crank shaft is the main one that goes in to the engine / gearbox, and the cam shaft(s) run the engine internals I'm guessing.
Click to expand...

Cam just runs the valves really.
 
Ok so theres multiple combustion chambers, each with 2 cylinders. cars are in my experience from memory 6 or 8 cylinder and I'm sure more varieties around that.
So logically the most efficient way to use multiple combustion chambers to drive a vehicle better is to have them on staggered timing on the same shaft. So one triggers and part of the turn from that is supplemented by the next one triggering etc. But this would ofcourse mean that all of them firing at once would break the engine.
This would explain the need for the distributer.
But surely if each of these chambers transferred its power to a gear connected to the primary shaft then the timing wouldnt matter and they could all fire whenever, and still provide extra torque to the vehicle?
 
oxygene said:
Ok so theres multiple combustion chambers, each with 2 cylinders. cars are in my experience from memory 6 or 8 cylinder and I'm sure more varieties around that.
Click to expand...

Each cylinder is a combustion chamber, so for example, your car will be a 4 cylinder engine.

oxygene said:
So logically the most efficient way to use multiple combustion chambers to drive a vehicle better is to have them on staggered timing on the same shaft. So one triggers and part of the turn from that is supplemented by the next one triggering etc. But this would ofcourse mean that all of them firing at once would break the engine.
Click to expand...

The crank shaft isn't a straight shaft....to wiki for another animation....

http://en.wikipedia.org/wiki/Crankshaft

Mechanically with regards to the cylinders, all the crank does is be driven around by the pistons and drive the pistons around.

oxygene said:
This would explain the need for the distributer.
But surely if each of these chambers transferred its power to a gear connected to the primary shaft then the timing wouldnt matter and they could all fire whenever, and still provide extra torque to the vehicle?
Click to expand...

The distributor just provides a spark to the cylinders at the right time.
 
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