Car battery - Maintanence Free

This type of battery comes with a seal so that you couldn't pry open the cover for adding water to the electrolyte. Such batteries typically have a clearly written note saying "Do not open". These batteries due to their inherent behavior don't need an electrolyte recharge.
In the same note, maintanence accessible batteries need electrolyte recharge. NOTE: Dont use any water other than distilled water for this purpose, as tap water might have chlorine and other chemical contamination that might reduce the purity of the electrolyte and in some cases lead to reduce shelf life of the battery

Yoko

Race Car Flywheel Moment of Inertia

For race cars, lower flywheel inertia is better for the following reasons.
1. Quick Acceleration - because most of the power is available for the vehicle (we dont have to spin a beefier flywheel)
2. quick decelration - due to lower rotational inertia of the flywheel during braking or turning.
3. Lower rotational parts means lower static parts too..thus a lighter powertrain and hence better gas mileage
4. Lesser horsepower requirement - Due to lower inertia rotation parts, needs lesser horsepower to accelerate.

Yoko

yatch design links

Here are some very good links listed on yatch and boat designs across the world.

http://www.svensons.com/boat/
http://robroy.dyndns.info/boats/sunapee/
http://www.bruceroberts.com/
http://boatdesign.net/plans/index.htm
http://www.westlawn.edu/index.html
http://www.bateau.com/index.php
http://www.farrdesign.com/316.htm
http://ants.dif.um.es/~humberto/yacht.html
http://www.tedbrewer.com/yachtdesign.html
http://www.tomfexas.com/

Ciao
Yoko

Brake problems syptoms

- The car pulling to one side during braking.
- Squeaks, grinding or other noises when the brakes are applied.
- The pedal goes farther toward the floor than normal.
- The pedal pulsates during regular (non-panic) braking.
- Evidence of brake fluid inside the tire/wheel or on the ground.

Powertrain Courses - Links

Univ of Michigan:
http://arc.engin.umich.edu/arc/contact/index.html
http://me.engin.umich.edu/autolab/index.html

Ohio State Univ:
http://car.eng.ohio-state.edu/education/disted.shtml

Univ of Wisconsin:
http://mees.engr.wisc.edu/index.lasso

Wet exhaust manifolds

Marine engine applications use sea water or fresh water to cool the exhasut system. Water is thrwon into the collector pipe which is then spit out off the exhaust pipe. these pipes are sometimes made of fibre reinforced plastics ( FRP) and can withstand very high temperature gradients.
This is different from usual road applications that we see.

wheel hop feeling at the wheel, when you drive ???

Wheel hoping feeling at the steering wheel, as you drive at low speed. this feeling is pretty cyclic ad can be sometimes really irritating. Here are a few possibilities that might be thought of
1. Wheel bearing needs to be changed. Check if your bearing is presfit on the shaft.
2. Unevenly bent wheel rim due to something else.
3. Check the CV joint and it cover as well.

Yoko

How to check front struts of the car ?

When the car is parked, try to grip and hold the car from the underside of either fenders and then try to lift the car and let go, look to see how hard or soft it is to lift and see how it springs back. Softer the lift, better your strut quality is.
This check is a must for all used cars thats up for sale.

Yoko

How to check tie-rod in a car ?

When the car is idling, try to turn the wheel either ways and try to listen for some kind of ticking sound as you spin the wheel.
If you hear the tick sound, then , for sure, your tie rod needs to be replaced or has to greased and tightened.

Yoko

what are tie rods ?

All vehicles, no matter what make or model have tie rod ends.On vehicles with Rack and Pinion Steering there are only two, but on others, there are four.The tie rod end attaches to the steering knuckle on each front wheel on Rack and Pinion Steering.On non-R&P steering, there is one attached to the steering knuckle on each front wheel and one attached to the long bar that controls both wheels for steering, called a Tie Rod Drag Link.This link is connected to the pitman arm coming from the steering gear-box and also connected to an idler arm for stability purposes.The little tie rod ends on non R&P screw into a sleeve with both right-handed threads and left-handed threads.
When you have the toe-in set on your vehicle, the technician can loosen two bolts and nuts and twist this sleeve¡...this makes the tires go out or in.It is very important to have these tie rod ends greased every time you have the oil and filter changed in the engine.The importance in greasing them is to keep them moving freely.If they get dry they will wear out quickly.

If they wear out, they can come apart. If they come apart, you won't be able to steer your vehicle. Not a good thing. Now, grant you, on some of the newer vehicles the manufacturers decided to leave off the grease fittings.These tie rods come pre-packed and will last a very long time.
But, you should have them 'checked ' at each oil change.Some have a threaded hole for the grease fitting, but they have a small cap over them.You can remove the cap and add a fitting so you can grease it.Any time you replace a tie rod end, be sure to grease it, and the others if you can.

How to improve your vehicles gas mileage

1: Check your tire pressure. If it is too low, add air to bring tires to their recommended pressure.
2: Check your air filter. If it is dirty or old, replace it.
3: Run your car's air conditioner less.
4: Drive calmly. Avoid unnecessary acceleration and braking.
5: Tune up your car if these steps do not improve your mileage.
6: Ask a mechanic to check the gap on your spark plugs. Adjust or replace as necessary.
7: Ask a mechanic to look for fouled fuel injectors. Replace them as necessary.
8: Replace spark plug wires.
9: Fill unadultered gas from a decent/same gas station as much as possible.
Tips & Warnings
Sport utility vehicles naturally have poor fuel efficiency, mainly due to their large size.
If you cannot improve your car's gas mileage, seek ways to lower fuel consumption. When possible, walk, ride a bicycle, or form a carpool.
Depending on your car's make and model, driving with the windows rolled down instead of running the air conditioning may cause increased drag, and therefore be less efficient than running the air conditioning with the windows up.
If your gas mileage suddenly plummets, see a mechanic. Your car may have a serious problem.