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Does starting your engine (manual transmission of course) by put ur car into 6th or 5th gear at 30 mph damange ur engine, clutch , or tranny? Also does starting ur engine (by means of a starter motor) cause wear and tear on ur engine?

The car i use is a g37s 2008 thanks

Hi,

There are dozens of us who bump start our MT cars hundreds of times/day, with no problems.

I started bump starting my car and it is smooth when you get it down. Seems easier on the car then turning the key it is so smooth.

Here's my $0.02:

1) Restarting a warm engine is a lot easier on the internal parts than starting cold, because the oil remains on the parts for several minutes after running. To see this firsthand, remove your dipstick and see how long it takes for the oil to run off and leave the metal totally bare.
2) Restarting a warm engine is a lot easier on the starter than starting cold, because the duration of the start is so short. Starter wear occurs with heat, so the starts that really bring it down are the long coughing cold starts. When warm your engine should relight almost instantly. Well, maybe it depends on the car, maybe some solenoids or other parts will wear even with short starts. Still, in practice, it doesn't seem to be a factor.
3) Bump starting is easier on the transmission than starting from a stop. I think this just because of the way it feels. The clutch is what wears, and wear occurs with slippage and increases with torque. A smooth bump start doesn't involve much slippage and the torque isn't really high either, especially in comparison to coming out of a full stop.

But don't ever hit start if the engine is actually still running. That horrible sound it makes is rapid death. Make sure it's really off when you shut it off. Some engines will spin for a few seconds while keyed off, if you switch it back on before it stops then it will come back to life, and it can be quiet about it. (I've done that a few times. Yuck.)

I'm suspicious on my oldest car that bump starting also wears my engine block mounts a bit (because of the way it feels), but this has a lot to do with the age of the car and other component wear, and again in practice it doesn't seem to matter much.

Overall I would bet each bump or keyed start is worth less than a tenth of the wear in each cold start, and maybe more like a hundredth, more especially if it's executed well.

I only have a couple personal data points to add.

Clutch:
I'm still on my original clutch and it's not even starting to slip. 177,000 miles and counting. I was not kind to it when it was young, and I've been bump-starting like a crazy thing in recent years.

Starter:
Still on my original starter.
On the other hand, I had to replace the starter in the van, at 65,000 miles. It's my wife's vehicle and is not hypermiled. I blame a production defect. If the "abused" starter lasts 3 times longer than the "babied" starter, I don't think there's that much extra wear happening.

Hi, as long as the engine is warmed up there should be no wear and tear bump starting a engine, I have been doing it for over 30 years and never had a problem with the clutch or gearbox on any of my cars. If you think about it downshifting is going to put the same amount of stress on powertrain components too.

Neddy Seagoon.

Thanks for that, Neddy. Nice to see some long-term observations.

Thanks for the long term and short term feedback on this topic!

I was seriously wondering about the implications of this myself as I do a bit of both, starter and clutch depending on the situation and speed. Slower speeds don't seem to bump my engine well, takes too long to start - seems like a more violent start (perhaps I need to check the sparkplugs?), so I use the starter when under 30mph. Over 30 it instantly starts in 4th gear and goes.

I bet I will replace the ignition switch sooner due to electrical contact wear from FASing than the clutch or the starter,

Scot

I was seriously wondering about the implications of this myself as I do a bit of both, starter and clutch depending on the situation and speed. Slower speeds don't seem to bump my engine well, takes too long to start - seems like a more violent start (perhaps I need to check the sparkplugs?), so I use the starter when under 30mph. Over 30 it instantly starts in 4th gear and goes.


As you say, that sounds like old spark plugs.

I find that below around 5 mph the bump start is too violent in my cars. At 5-20 mph I use 4th, above 20 mph I use 5th. My rationale is 1) that feels right in my cars, 2) I'd expect the sweet gear to be 2-4x higher than the one I would use to drive at that speed, because starting is normally 400-900 rpm, whereas driving should be 1500-3500 rpm. Given a choice, a higher gear is generally better for bumping because it gives the wheels more leverage over the engine, provided that the engine rpm is above starting threshold. In principle I ought to be able to bump in 3rd or 2nd below 5 mph but I think in practice there just isn't enough energy in my roll for me to bump without approaching a stall. The engine rpm is higher than it needs to be when bumping above 40 mph, so I just keep it short (it shouldn't hurt anything to "start too much", but the extra rpm means extra drag on the wheels, similar to applying the brakes, so minimal is more efficient).

Then again, I'm driving sedans and you're driving a truck which means that you're engine volume is a lot higher per pound of vehicle, so you may find that your bumping thresholds are higher than mine even when everything else is ideal. But I'd still check the plugs if they're old.

When I bump start regardless of vehicle speed I'm always in 5th gear. I don't do this as much as I restart with the starter. Any use of the clutch is wear, including downshifting which I never do anymore unless I'm going down a mountain (not likely).

This is my theory & I'm still testing it. Starters for starting and brakes for slowing are cheaper and easier to replace than clutches for bump starting and clutches for downshifting.
:D - Dale

Here's my $0.02:

1) Restarting a warm engine is a lot easier on the internal parts than starting cold, because the oil remains on the parts for several minutes after running. To see this firsthand, remove your dipstick and see how long it takes for the oil to run off and leave the metal totally bare.
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I'm suspicious on my oldest car that bump starting also wears my engine block mounts a bit (because of the way it feels), but this has a lot to do with the age of the car and other component wear, and again in practice it doesn't seem to matter much.
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Good point on the oil taking a min or 2. that is about my only worry. Keeping the engine lubricated.

I'm not at all worried about the engine mounts, Or anything else from bump starting. I have driven clutches for 30 years, from a VW bug to a 10 speed truck. Downshifting is a part of driving (more so in a truck) IMO downshifting puts as much or more stress on the mounts and drive-train then bump start.

1 other benefit from bump start. I feel my car uses a little extra gas during the key-start, bump starting avoids that extra fuel use.