Tip & How-To about 1998 Ford Explorer

2006-2009 Ford Explorer/Mountaineer

Issue.... is those equipped with 4.0L engine may experience coolant leaking from the coolant expansion tank. This may be due to cracks that develop in the tank at the radiator mounting bolts locations. The action to be taken is replace the tank.

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3 Answers

what is the reason for losing water/

could be you have a leak in one of you hose,s

Dec 08, 2012 | Cars & Trucks

1 Answer

1999 XK 8 engine, we cannot keep coolant in the expansion tank and engine idles rough

if it is not keeping collant in the tank due to overheating then it is the water pump bot if it just leaks out the you might have a leak in the tank.or maybe head gasket

Jun 06, 2012 | 1999 Jaguar XK8

1 Answer

Internal engine is leaking radiator fluid

If you are leaking coolant from the radiator then most likely it is on the driver's side of the radiator and there is a crack in the end tank. This is a common problem and requires the radiator to be replaced.

If you are talking about a leak inside the engine then some signs to look for is a chocolate milkshake look in the coolant expansion tank and then a coolant smell and look on the oil dipstick. If either of those is the case you have a blown head gasket. But my money is on the cracked radiator end tank.

Feb 22, 2010 | 1999 Saturn SL

1 Answer

Water leak from top of expansion tank.2000 BMW 316i se

The water (coolant) in the expansion tank will rise and fall with the engine temperature. What the expansion tank does is collect and return coolant to and from the engine. When the engine warms up the coolant gets hot, builds up pressure and opens up the radiator cap. The coolant then goes into the expansion tank. Now when the engine cools down the pressure drops in the cooling system and the pressure drop (vacuum) pulls the coolant back into the engine via the radiator cap. The radiator cap allows the cooling system to build up pressure and by doing so increases the boiling point of the coolant, but when that pressure exceeds the caps rating the cap opens and the coolant goes to the expansion valve. The cap has another part to it that when the engine cools down and a partial vacuum is created in the cooling system a "valve" in the radiator cap opens and allows the coolant to be drawn back into the engine. I would look at your radiator cap to see if any gunk or build up is on it, and check the rubber gaskets for cracks. It's easiest just to replace the cap because they are inexpensive and easy to replace (2-10 dollars). The expansion tank should have two hoses on it. The one on the bottom comes from the radiator and the one on the top (possibly part of filler cap) runs down and is open to the ground. That way if it is overfilled or becomes overfilled it will slowly leak onto the ground. When and if you change your radiator cap, make sure the engine is cooled down, remove cap and start engine and turn heater to full blast, full heat. Leave the cap off and let it run until engine warmed up. This should burp out any air pockets that may have happened when coolant was changed. Also top off the coolant in the radiator while it is running. Hope this helps and good luck

Apr 03, 2009 | 1992 BMW 3 Series

1 Answer

symbol lit up

there can be a yellow light in the cluster that looks like a small radiator or box with waves inside of it to indicate water. This light means that the coolant level sensor has detected a low coolant level. Typically the expansion tanks inside of these cars will crack from heat and age. A simple diagnosis is to check your coolant level and top it off. Do not forget to bleed it by unscrewing the bleeder screw found on the upper radiator hose while filling up the reservoir found on the right hand side of the radiator. once the coolant has been filled, tighten the bleeder screw back down but be careful not to over tighten. and finally screw on the expansion tank cap. run the vehicle to operating temperature and use a flashlight to inspect the engine bay for leaks. If there is a leak, it will need to be repaired. possible leaks are a cracked expansion tank, leaking radiator hoses, or a leaking water pump or thermostat.

Oct 29, 2008 | 2001 BMW 325

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