Bmw318ti 1998 so i turn on my car with the radiator cap off it doesnt take long for the car to start spilling out water as if it was hot meter marks its still cold hasnt even reached the middle between hot and cold ive replaced head gasckets nd water pump and problem still persist please help

Open the container of antifreeze. Using a separate EMPTY gallon-size container, pour out HALF of the contents into the empty container, making sure not to spill any. Now, FILL the newly filled container with tap water. Fill the rest of the antifreeze with water, also. Now, you are ready to add antifreeze to your vehicle! Simply locate the radiator cap, (Don't touch it if it's hot!!) and unscrew it. Pour the desired amount of your mixed antifreeze into the radiator. Remember not to do this without proper knowledge!

Quote "and no coolant in my engine." Put some in

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1998 BMW 318ti Electrical Troubleshooting Manual ETM

What is this cap on?? Radiator or windshield washer reservoir? Something else?

If the radiator, most newer cars have a plastic bottle or tank that has a "cold" and "hot" level indicated. You should be able to see the coolant level thru the tank. You should NOT need to open the radiator cap if your car has this tank. Add a 50/50 mixture of water and coolant (of a type your car requires) up to the "cold" mark and start the car. Let it run with the heater set to HOT and fan set to HIGH. Continue adding the 50/50 mixture to maintain the coolant level to the HOT level mark on the tank as needed with the engine running. Stop when there is HOT air blowing out of the heater.

If your car does NOT have this tank, you may only open the radiator directly when the engine is COLD. Wait several hours for the engine to cool after shutting off before attempting to remove the cap.

When cold, press DOWN on the cap WHILE turning. Most caps will come off after a 1/4 to a 1/2 turn. Start the engine and set heater HOT and fan to HIGH. Continue to add a 50/50 mixture of coolant to the radiator until the heater blows HOT air. The coolant level in the radiator should be just under (1" or less) from the bottom of the radiator opening.

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You can get a kit for that at an autoparts store. You cut the line to the heater core and install a plastic T that has a hose connection. Then you open the drain and the radiator cap and start the engine and turn on the water BUT the antifreeze goes everywhere and that is an environmental issue. So to be safe, take it into a quick lube store, they can drain it and refill it and not spill a drop.

replace thermostat.then bleed coolant system, this is how you do it.fill the cooling coolant system with 50 / 50 dexcool and water to raise boiling point,straight water will evaporate boil away cause engine to overheat catch fire thats why you need 50 / 50 mixture antifreeze and water.to bleed coolant system first fill coolant system until coolant stay at the full cold mark on the the coolant overflow jug,then you start engine allow it to idle,place the heater and ac control in any ac setting except max and the temperature control to the highest setting,run engine until lower hose to water pump is hot. with the engine hot run the engine speed up to 3000 rpm and allow it return to idle, repeat this 5 times. slowly open the bleed valve on the thermostat housing or look for bleed valve at the water pump heater hose.open bleed valve for 15 seconds to expel any trapped air.then top off the coolant as necessary,and when top radiator hose hot thermostat open up.keep adding cooling to overflow until coolant level stop at full cold mark dont over fill coolant.if engine seem like overheating while looking at cooling gauge turn off engine wait a while until cool off add more coolant until coolant level stay stable and dont drop any.when open radiator overflow cap use large rag over the radiator cap to keep from getting scald open radiator cap a little at a time but dont open radiator cap until engine cool down first.replace the radiator overflow cap, thermostat,and engine coolant temperature sensor and check the cooling fans fuses and relays see what happens.

you need to replace thermostat and radiator cap.look under hood around engine compartment.look for a radiator cap near radiator,add 50/50 antifreeze and water to coolant system to bring up boiling point.pure water will cause engine run hotter because water evaporate away,remove radiator pour coolant in the radiator until coolant stop dropping in the radiator now some vechicle pour coolant in the coolant overflow jug,pour coolant until coolant level stop dropping and the coolant level stay at cold full mark.start engie let idle few minutes, watch coolant level in radiator if coolant start dropping add more coolant, when coolant level stop dropping put radiator cap back on let engine idle until both top radaitor hose and bottom coolant hose get warm turn off engine wait until it get cool then take a large rag slightly open radiator just a litle at a time to keep from getting scaled.once radiator remove add more coolant if low,put radiator cap back on start the engine let it idle watch the temp gauge if temperature gauge going hot zone stop engine wait until cool then add more coolant,keep doing this until engine stop overheating going into hot zone and coolant level stop dropping,make the coolant overflow jug coolant level stay at full cold mark, dont let jug run empty if so air will get in the coolant system causing engine to overheat.

When engine is cool, take off radiator cap, and fill radiator. Then fill the coolant recovery container to halfway between the full cold mark and the full hot mark. Start engine (with radiator cap still off) and wait for the thermostat to open (upper radiator hose will get hot). Shut off engine, top up radiator, and put the radiator cap on. Fill the coolant recovery tank to the full hot mark.
You should mix the water and anti-freeze in a 50/50 mix before putting it in the car, you know. Cheers.

IF THERE IS NO RADIATOR CAP ON TOP OF THE RADIATOR, YOU SHOULD SEE A SMALL HOSE TO THE TOP OF THE RADIATOR FOLLOW THAT TO ONE SIDE OR THE OTHER, THERE WILL BE A WHITE OR YELLOWISH CONTAINER ON THE WHEEL WELL, WITH A CAP ON TOP! IT USUALLY HAS COOLANT PRINTED ON IT! THAT IS WHERE YOU CAN PUT THE COOLANT!

open the hood in the front of the car when the engine is cold only remove the radiator cap start the car and fill it up the engine will get to its running temperature when its full put radiator cap back on there it is thanks pierre