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A blown radiator hose or broken belt won't kill you, but it can certainly strand you in the middle of nowhere. (In these violent times that might just be a matter of life and death!) On some cars a broken timing belt can DESTROY YOUR ENGINE IN AN INSTANT, which will certainly hurt your wallet! Rubber goes bad with time regardless of mileage. Any car which has over 5 years or 50,000 miles should have every belt and hose replaced.
A hose usually swells, or gets soft or hardened. A hose normally fails next to the hose clamp, and usually on the engine side, because that side gets hotter. A good hose is flexible and free of swelling or cracks. Oil on a belt or hose is bad news: oil dissolves and softens rubber. This is one more reason to keep your engine clean!
Here's more serpentine belt pictures
Before any of these symptoms occur, bad hoses develop cracks, and soft spots. Like all rubber stuff hoses don't like oil, so examine any hoses that have gotten oil on them carefully. If oil is getting on a hose, clean it off. This is one good reason for keeping your engine clean. If a hose has gotten "oily" clean it off and feel it. If it feels softer, or even just different from the rest of the hose, REPLACE IT!
Look at the ends of the hoses, especially the "engine" end. There should be no swelling behind the hose clamp where the hose connects to the motor. This is where a hose often fails.
But the general agreement is that it's not cool to dump it out on the ground.
GREEN, ORANGE, OR RUSTY WATER means an engine coolant leak.
CLEAR WATER can leak from under a car as normal operaton. The most common is the air conditioner: it can drip out an impressive amount of water. Some body panels on a car have drain holes: rainwater can drain out of them for a few minutes after you park.
One advantage : this way you can open the hood, lay the box across the engine compartment, and look straight down from the spot to locate a leak. The same applies if you have to crawl under the car: the pizza box is your "map" or "x-ray" of the leak location.
You can use this to diagnose a leak on your car: if you "don't know what to sniff for" you can get a sample easily enough:
Don't break down! Check your belt and hose condition regularly!A bad belt or hose can hurt you!
Suppose you knew there was a ticking time bomb under your hood. Would you keep on driving until it went off?INSPECT YOUR BELT!
Inspect your belt or belts regularly: a good time is when you change your oil. Before you go on a long trip it's a good idea to look for a bad belt or hose. Look for cracks on the inside of the belt: if you find any, replace ithe belt. If a belt "squeals" or makes noise, check the belt tension. If the tension is OK, a "squeaky" belt probably needs replacement, no matter how it looks.
Belt Types
Most cars have either a single serpentine belt (also called a multi-groove belt), or multiple "vee" belts. These are called accessory drive belts, since they drive the alternator, air conditioning compressor, and sometimes the water pump, among other "accessories". The serpentine or multi-groove belt is flat with 3 to 6 grooves. Most newer cars have this type of belt. The older style "vee" belt is narrower and thicker than a multi-groove belt, and has a "vee" shaped cross section. Some cars have 2 or more serpentine (multi-groove) belts, or a combination of "vee" and serpentine belts. Motors with timing belts have a belt called a "Cog Belt", or "Gilmer Belt" connecting the crankshaft to the camshaft. Sometimes this belt also drives the water pump, or oil pump, or balace shaft(s). When a timing belt breaks it can destroy your motor instantly!!!
Belt service
Most newer serpentine belt equipped cars have a spring loaded belt tensioner and no service is needed besides replacement when cracks develop. Other cars, and all "vee belt" applications, may need periodic re-tensioning of the belt. The most noticeable symptom of a loose belt is a squealing from under the hood, often while parallel parking (loose power steering belt), or when you turn the A/C on (loose air conditioner compressor belt).
Bad Hose Symptoms
The SECOND most obvious symptom of bad hoses are are green or orange spots on your driveway, overheating, and a constant need to add radiator coolant. The MOST obvious symptom is smoke pouring from under your hood as you stand by the side of the road waiting on a tow truck.COLLAPSING HOSES
Sometimes a top radiator hose will collapse when the engine cools off, especially in cold weather. Better quality hoses often have a coil of wire inside them to prevent them from collapsing. The reason the hose collapses is this: Water expands when it gets hot. The cooling system in a car is actually pressurized when at normal temperature. (180-190 deg F.) The radiator cap releases excess pressure. When it cools off a vacuum is created which can collapse the radiator hose. When the cooling system comes under a vacuum, the radiator cap should allow either air or coolant from the coolant recovery tank back into the system. A defective radiator cap could cause too much vacuum to build up in the cooling sysem, collapsing a hose. A pinched or clogged hose between the coolant recovery tank and the radiator could also cause excessive vacuum and hose collapse. Another cause would be improper bleeding of air from the cooling system after replacing a hose or something. It could be a bad new hose: A low quality radiator hose can collapse under very little vacuum: SOME vacuum is normal for a sealed cooling system.
How a Pressurized Cooling System Works
Most all cooling systems are pressurized. Coolant under pressure boils at a higher temperature, so a cooling system can tolerate higher engine temperatures without boiling over, losing coolant, and eventually overheating.
Radiator cap: the pressure enforcer
Cooling System Pressure is maintained by the radiator cap. Caps are rated in pounds, the pound rating being the pressure at which the cap will hold pressure in the radiator. Above that pressure the cap will "blow off" the excess pressure. On the older radiators the water or steam blowing past the radiator cap went out a hose and dumped on the ground. On the old style stuff, you NEVER fill the radiator up all the way: you leave an inch or so at the top empty so the water can expand. If you DO fill one of these old systems up all the way, it will just dump out coolant as it expands, and when it cools off there will be the inch or so of air that should have been left there in the first place. That just ain't green!
ACTUALLY (except for OAT, which is orange, and the Toyota stuff (Red)) ANTIFREEZE IS GREEN!!!Coolant Recovery Tanks
Cars today have some kind of coolant recovery system, or a "Sealed Cooling System" The first, and still common, type just took the same old hose at the cap and stuck it in a plastic bottle by the radiator or on one fender. These are called "Coolant Recovery Tanks". The water would heat up, blow out into the tank, then get sucked back in when the engine cooled off. A lot of newer cars have a plastic coolant tank at the high point of the cooling system, usually near the firewall. These tanks are meant to be kept half full: if you fill them up to the top they'll just blow coolant out on the ground until they're about half full when cold.
Fluid Color Coding
You can tell a leak by its spots!
If you see spots on your driveway the color can tell you what's leaking: Here's the "color code"
DARK BROWN TO BLACK SPOTS are engine oil leaks
RED TO BROWNISH RED SPOTS are transmission fluid leaks or power steering leaks
NOTE: Front wheel drive vehicles and many others have rubber transmission cooler lines which can go bad: look for cracks and leaks at the connections
RED, AMBER, DARK GREEN spots can be power steering fluidA CUTE WAY TO CHECK FOR LEAKS
Not sure if a spot on the driveway is your leak? Here's a cute trick check for a leak! Order a pizza. Eat it. Unfold the box and slide it under the car, clean side up. In the morning remove the box: look for spots.Oo-o That Smell!!!
Many fluids can be diagnosed by smell. 90 wt gear oil (used in some manual transmissions) looks very much like engine oil, especially when it's spread all over the underside of a vehicle! That smell, though, is unmistakeable. 90 wt gear oil has a very distinctive smell. (Oo-o it's nasty!)
Engine oil and automatic transmission fluid sample at dipstick tubes
Coolant sample at coolant recovery tank or radiator cap ON COLD ENGINE ONLY!!