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I know the standard bad stuff that damages your clutch: feathering too long, riding the clutch, etc.

But, what actually causes damage to the engine?

Stalling

  1. Can stalling damage the engine?
    • I've heard this only damages it if it is done many times.

Dropping the Clutch

  1. Does dropping the clutch damage the engine?
  2. How high of an RPM is considered "dropping the clutch"?
  3. Does letting off the clutch quickly when starting off (1.7-2.0k rpm) damage the engine?
    • Are cars designed to take that small shock?
  4. What exactly would someone dropping the clutch damage?

Other

  1. Is there anything else?
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    You're predominantly 'damaging' the clutch, well, not really damaging but wearing it out fast. The engine won't necessarily wear out that much from it, unless you completely let go of the clutch when it's revved above 2500rpm. The inertia of moving parts in the engine get stressed heavily at that point, because of the sudden angular deceleration. But even then, there's springs in the clutch cap off the biggest peaks. – Bart Nov 8 '16 at 9:43
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to keep a clutch in good shape you want to start off connecting the clutch quickly at low RPMs. If the engine dips to about 700 rpm, and you start taking off, without slipping the clutch much at all, this is the best way to keep a clutch in good condition. Also once you are off take your foot off the clutch entirely else you can wear out your throwout bearing or even accidentally ride the clutch without knowing it.

I typically start connecting the clutch just off idle at about 1k RPM. Let the engine dip to about 700 RPM and I should be off on flat ground.

This can have an effect on oil pressure so once your foot is completely off the clutch and you're back to 1kRPM don't just floor it.

When shifting while driving try to match the engine RPM and trans RPM and don't be a racecar driver down shifting all the time just set it to neutral. Matching the RPMs means essentially there is no slipping at all and therefor no wear.

You already mentioned the big things about dropping it stalling and whatnot so I think your good to go.


sounds like your clutch pads are sticking and releasing. have you looked at your engine and transmission mounts? you could be moving the whole drive train and then the clutch releases and it all falls back down. Set the break pop the hood have someone check it and lightly connect the clutch but not hard enough to stall and not with too many revs so near idle. See if the someone watching the engine notices it move an abnormal amount. you could also try picking it up with a cherry picker and see if it moves abnormally but be careful and don't pull up too hard you could damage something like the good engine mounts.

this could also be something else that is winding up then letting go too. but check the engine mounts you may have a bad one.

a little over 1 k is still fine its just the lower the rpm and the quicker you can let off the pedal the less clutch wear there will be. revving higher only adds clutch wear and just over 1k isn't that much.

  • On my car (A 16' Golf) the clutch is notoriously "Shaky" so anything below 1.5k will vibrate like crazy (I've heard it's just a very light flywheel?). But it's a very small engine. So I feel like I need to give it more gas. But I guess a little over 1k is still not bad? – msmith1114 Nov 8 '16 at 16:33
  • I saw your post edit, for reference this car is known to have very weak motor mounts stock (the car has less than 6k on it). But maybe thats what im feeling (the vibration/etc...) – msmith1114 Nov 9 '16 at 17:56
  • @msmith1114 so it's brand new? and doing that? – Cc Dd Nov 10 '16 at 0:20
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Just to add... There are many parts that will take the load and wear more quickly from bad driving practices such as dropping the clutch and rough gear changes etc.. The main clutch ones are... The clutch driven plate and clutch cover.. And yes this is made to "take the shock" of gear changes BUT rough treatment wont help it at all.

Basically the clutch is only a disc of friction material (like a circular brake pad) with springs in it that connects and disconnects the transmission from the engine, allowing you to gradually move off from stationary and change gear without the severity and harshness of a direct drive type system.

Not only will the clutch be affected by fast launches and rough changes but parts like engine mountings, exhaust systems, drive train components and driven tyres etc will all suffer the effects of a rough driver.. Not to mention the gearbox internals themselves, as the shock and loads are put upon the system as a whole. Synchronisers, gear faces, bearings and forks within the transmission are also taking that rough treatment too.

Of course many of the things I mention occur over time, but that amount of time decreases as long as rough treatment continues. And whilst in a lot of cases rough driving may not actually break anything initially.. A good technician or driver can always tell when a car has had a rough life by driving it, as all the parts in the system as a whole just feel loose and worn, with rattles and noises emanating from parts that have become slack.

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The real thing that will damage your engine in a manual is revving it too high, either by downshifting too dramatically (like shifting into first while doing 50 mph) or not shifting when you should (before 3000 rpm on many cars).

Redlining your car while street racing may seem cool, but it exponentially increases engine wear. You can blow a gasket or bend a valve or crack a head on the spot. That's the real (and very expensive) danger.

Quite simply, every turn of the engine is more wear on the parts, so the higher your RPMs are on average, the quicker you're going to need to do engine work.

Stalling doesn't damage the engine. Popping or dropping the clutch above 2500 rpm will technically put wear on the engine, but it's negligible. The other stuff mentioned does wear the clutch, however, a clutch is a replaceable part (I won't go as far as to say disposable, but replacing a clutch is something people do) and most cars will go through 2 clutches before they need major engine work.

This doesn't include the damage that poor diving habits put on the rest of the car: tires, transmission, suspension, engine mounts, etc.

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Aside from the answers above about looking after your clutch, the top thing that will damage the entire drivetrain is shock loading. You can feel if you're doing that - basically any time you make the vehicle "jerk" or jump or the tyres "chirp" as you bring the clutch up, you've just sent a big shock through everything from the tyres to the piston (via the driveshafts, CV's, diffs, gearbox, clutch, crank, conrods, etc. etc.) and it is bad for your vehicle.

Shock loads are many, many times greater than the regular loads the vehicle experiences and are an easy way to snap things, strip gear teeth off, etc. etc.

It also wears out things like engine mounts and suspension bushings much faster as the engine tries to twist off its mountings in reaction.

The classic example off-road is when you see someone get a wheel or two in the air for whatever reason, spinning wildly (because they've got their foot down) and then it lands & grips on the ground and something in the drivetrain goes BANG! - that's because the driveshafts and everything were spinning madly and then instantly STOP as the wheel touches down, and whatever bit is weakest will break under the shock.

Lots of off-roaders (esp. in the the US) run automatics for the reason that the torque converter cushions many of these shocks, acting like a bucket of custard. I prefer manual so I just try not to drive like a knob and to dip the clutch if the vehicle's about to take a hit.

In general, it's a reasonable idea to heed Sir Jackie Stewart's advice - driving smoothly is better all round, and faster. That's not a quote, but he did train people in that doctrine, and you can see the best drivers are generally smooth and calm.

The easiest way to learn how to drive smoothly is to place (or imagine) a very full cup of boiling hot coffee on or near your lap, and any sudden movements will spill it. That or a wedding cake on the back seat, or a cartoon bomb that doesn't like being jiggled about... you get the idea.

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