Turning off ignition at stoplights = starter wear?

[Drag Limited]

I was just wondering if the 3-4 extra starts a day by turning off ignition when approaching stop lights (that I know are slow changing lights) will cause pre-mature wear to the point I should be worried? or if the gas savings are even worth it for .5-2 mins of waiting?

[omgwtfbyobbq]

Starter wear and gas savings are small, although I would say that starter wear is much smaller than gas savings. IIRC a starter should last ~200-500k starts. What kills them prematurely is too little voltage/excessive cranking which generates excessive heat. As long as those extra starts don't involve this, I think you'll be fine. Along those lines, make sure your battery is in good shape.

[GasSavers_Ryland]

Also with a warm engine the car will start sooner, so it's less wear on the starter then a cold start would give, and your battery should be fully charged at that point as well so less electrical stress on the windings.

[Drag Limited]

Thanks, my battery is showing some corrosion around the terminals, is that going to be a sign of wear / need of replacement?

[GasSavers_SD26]

Corrosion around the terminal just means it needs cleaning. Whether that corrosion has damaged the post of the cable terminal will be what you need to look at.

[8307c4]

I've been doing ICE Off's for 7-8 years now, I have replaced one starter in this time...
Which, that's roughly in line with normal wear and tear specifications, or maybe I should say at least from my own experience this does not strike me as something outside of the norm.

As for the battery, those posts likely need a good cleaning and then have to check them regularly, they sell a tool for like $1 or $2 at the auto parts store, it's appropriately called a 'Battery Post Cleaner' but it is a tool not some fancy chemical heh

[thecheese429]

I agree with everything previously said in this thread, but has anyone addressed engine wear? I am willing to do eoc-ing , but I'm worried about taking years off my engine's life when starting it . the way I understand it, the engine experiences the most wear in the few seconds right after starting, and that worries me about starting it every few minutes . it doesn't help that on my jeep you can feel the engine quite well, as it doesn't have the best vibration dampeners underhood. even if I wait 3~4 seconds before accelerating, how much does this wear the engine, and what parts specifically?

[JanGeo]

Every time the piston rings stop moving they make contact with the cylinder walls and cause wear. They stop at the top and the bottom of the bore all the time that is why there is usually more wear there. Bearing surfaces will be exposed to the same added wear every time you stop and start the engine and the oil will be hot - could be really hot - hotter than the coolent thus thinner when you hot start every time increasing the wear. Plus you thermal cycle the Cat and exhaust system every time you stop the engine and start it again.

[jasonty]

I'll give you all my opinion based upon the fact that I'm a forklift mechanic for Toyota, and have 8 years of mechanical experience in both automotive and heavy equipment.

As stated above, the most damage does occur to your engine during a cold start. The oil is thick (cold) and the bearings are not well lubricated due to the fact that the oil has had time to drain down to the oil pan. Crank, rod, and cam bearings are now designed with this in mind. If you hold a crank or rod bearing to a magnet you'll notice that one side attracts more than the other, because the top side of the magnet is made of materials that are resistant to constant wear better than the other side. So it's really not an issue anymore, it's more or less just what people have heard about 60's cars, and tell their kids, and so on. Such as teenagers still pumping the gas pedal 3 times before they start up their fuel injected car.

I have seen engines go through extremely heavy use not only as a Toyota forklift mechanic which uses a gas or LP Toyota 4Y engine, but also when I was a mechanic in the Air Force. The cars and trucks I worked on in the military saw much more abuse than you could ever imagine. Not because of the harsh environment, but because of the stupidity of the operators. 19 year old kids with a license, and not paying for the vehicles they operate, in any way. All in all, I have never seen complete crank or rod bearing failure, ever. I have seen damage due to improper lubrication of the bearings because of low oil level or a very dirty air filter, which also caused damage to the cylinder walls by letting dirt rub between the piston rings and the cylinder. Keep your oil and air filter clean!

Warming up an engine is the best preventative maintenance you can do, aside from changing your oil with a quality oil regularly. The oil needs to heat up and thin out to coat the tight tolerances of bearing surfaces. This is why cold starts may have damaged engines the most, but not necessarily true anymore. I have an 80 Camaro with 425,000 miles on it. I rebuilt the engine at 330,000 miles, not because of bearing failure, but because the camshaft and timing chain were wore out. I also have a 94 Civic with 210,000 miles that I bought off of a teenager who had beaten it up pretty bad. After pulling the cylinder head to replace the gasket that he blew, I found perfect walls, still with cross hatch machining marks from the factory.

Turning off a car and restarting at a stoplight will not damage your engine. It will cause premature starter wear due to heat and bendix contact with the flywheel, but honestly, you'd probably have to own your vehicle for at least 7 or 8 years to see some signs of damage.

[jasonty]

Also, in reply to what is stated above, the piston ring always has complete contact with the cylinder wall. If it did not, you would experience excessive blowby past the piston rings, which would result in high crankcase pressures. Piston rings don't require lubrication due to the material they're made of. That's why you have 2 compression rings, to hold the compression of ignition in the cylinder and not let it into the crankcase, and 2 oil control rings that scrape the oil from the cylinder walls before the compression rings even touch it. Oil will damage compression rings. They simply work best on friction principles. They are a very hard metal that is not near as hard as steel cylinder walls, which is why they can be replaced without boring out an engine. A cylinder does not receive more or less wear at any point of the stroke. It's an up and down motion. The most wear would normally be received at the top of a connecting rod bearing during the compression stroke when it is being thrown down from ignition. If you're talking about the dark circle at the top of the cylinder when you pull the head off, you're referring to the distance that the piston doesn't travel, which IN A WAY determines your compression ratio. This is the area that the fuel and spark ignite and cause combustion. The smaller the area, the higher the compression, but other aspects such as cylinder head quench also have to be considerered to make an accurate analysis of compression ratios.

Also, oil has to be MUCH hotter than coolant, all the time. Hot oil doesn't damage engines, lack of coolant to reduce high combustion temperatures does. Your engine needs to be VERY hot to operate properly. This is why throwing in a thermostat less than 160 degrees can damage an engine. Engines need a lot of heat to operate. The heating of the oil helps the engine move the oil quickly. The only circumstance where this is not true is in rotary engines where oil temperature can often times exceed the recommended temperatures, which is why ALL rotary engines use an external oil cooler, from the factory.