Remove the radiator cap and let the engine heat up until the electric cooling fan cycles on. Sorry, but your head gasket is blown. The stiffness of a radiator cap’s spring determines how much pressure the water is under. A leaky one cant. . I can turn over Any rad cap, there Is a spring, a poppet valve, two seals. I have a 02 pt cruiser change waterpump.thermostat radiator.hoses heater hoses clean heater coil.now heater works.didnt work before.bleed air out system.still overheats.water bubbles to radiator cap then the cap open ups and shoots the water to the resorvoir and the resorvoir dump out the water.then it overheat.been using distilled water because i cannot put coolant every 10miles.please help (4) Radiator cap tech. Never check the coolant level until the engine has cooled completely. The problem started 2 years ago when top radiator hose blew off going down highway. Not the cap on a sealed recovery tank system, no.There is No "radiator cap" on these, it isn't There. Many factors cause gurgling radiator. Could also be your thermostat got stuck shut. Have a contractor check it. Have you noticed any leaks? The radiator cap when bad will allow pressure to go back to the overflow bottle, after that check your thermostat. Don’t forget to check the radiator or the expansion tank. The upper radiator hose should feel hot to the touch. Don't try to use a pressure cap on the radiator, it can block the flow of water (and more important air bubbles) to the resivior. When an engine overheats it can force coolant into the overflow container which can create a bubbling sound. a clogged radiator can cause this to happen too, the coolant doesn't circulate fast enough and cause's localized boiling. Filled coolant system back up and put a screw type clamp on hose. Usually, if the radiator cap is unable to hold a specific pressure then the cap must be replaced. 1. The slightly higher than normal operating temperature happened since I had the OEM radiator. Leaks. Fans rarely fail, but temp sensors are a maintenance item. everything currently ok If you're seeing gas bubbles or some boiling in the liquid when you remove the radiator cap, a cracked head or block may be to blame. That can produce a "gurgling" sound. This can also be caused by a faulty radiator cap. A bad radiator cap can render the whole cooling system ineffective and cause costly damage to the precious engine. Both of these can cause a gurgling or bubbling sound, and are completely normal. then, install the radiator cap in place, turn off the engine and fill the coolant bottle to the max. Some other reasons can make coolant bubbling. A head gasket failure may be caused by an engine overheating one too many times (as a result of a clogged radiator, coolant leak, faulty fan, etc. Radiator cap, as you mentioned, which keeps the system from being properly pressurized. Mechanic's Assistant: Has the car been overheating? If HG blew, it wasn't due to leakey rad cap.Brandon you are Full Of It. The radiator cap controls the flow of coolant in and out of the over-flow container, and a faulty cap could definitely make this happen. Just a regular cooling system pressure cap. I thought it would fix the problem by installing the new one. No leaks, cold air out of the heater, overheated at least one time. Can a worn radiator cap allow air back into the cooling system and cause air bubble lockup of the cabin heater?. In this case, a pressurized coolant will pass toward the coolant line. the list goes on. 9 – A Defective Radiator Cap can Cause a Pressure Drop. One of the first symptoms commonly associated with a bad or failing coolant reservoir is the need to constantly add coolant. You can experience a shot of boiling water exploding under pressure. ... a bubble of air forms as water flows over or around an irregular surface in the radiator. Do not remove a radiator cap from a hot engine to check. Turn the interior heater on its maximum setting. I have a 2002 Dodge grand caravan, 3.3 engine. is there coolent in the resevoir? The vacuum won’t be released properly and it will cause the radiator hose, to collapse during the cooling down period. Three of the ways a radiator cap can cause overheating are, 1) Not holding in pressure and allowing the coolant to vent out or escape the cooling system. The OEM one was dirty inside plus the plastic covering cracked. Once a head gasket has failed it can cause all manner of problems, including: 1) Overheating. Fan isn't running. The sprung cap is located above the fluid level so allowing air in would not cause it to get into system. is the hose cracked? A faulty thermostat that causes sporadic opening and closing can cause a churning and bubbling effect seen in the radiator or expansion reservoir. Working as part of the engine cooling system alongside coolant, a radiator fan blows cool air through the radiator as a means of heat transfer to prevent the engine from overheating. This can be a problem – air trapped in the system can cause … Dodge Ram Truck 3rd Gen (02 – 08) Forums. I have never seen one in a parts store. The rapid closing and opening of the thermostat valve can also cause a pounding noise inside the radiator, due to the slamming pulses of coolant. Air pockets in the cooling system from an ineffective seal (such as one in a bad radiator cap) or a lack of sufficient pressure can cause the engine to overheat. From time to time the hose would be … BTW, a defective radiator cap will let air into the system over time, so if the cap is bad, it may have recently started to fail. If you blew a headgasket, and had a leaking radiator cap you probably had low coolant the engine got overheated and then the head gasket blew. If and when the temp gauge does say its overheating, the engine its self doesn't actually get hot, meaning i can touch it without burning my self, and only the cooling system smokes. In the Grand Cherokee WJ there is a screw that should be open, we will publish an article soon. To correct another answer here, the radiator cap doesn't have a spring in it. If not, wait until the thermostat opens and heats the hose. To ensure optimal performance and lifespan, your engine must not overheat. Had this exact same situation with my last car, I think I can tell you the most direct answer. A broken gasket or weak spring means the cap can… The aluminium radiator was given to me for free. In the Cherokee XJ you should fill the radiator with coolant and let the engine work and reach normal working temperature for at least 5-10 minutes. A failing radiator cap could cause it but I think you would see dried coolant around the filler neck as it would also allow coolant to bleed out when warm and under pressure, I had this coolant leakage on my Titan, they are known for it. Could be a bad temp sensor, wiring to the fan or the fan motor. Your local repair shop can perform test to identify cylinder head or engine block cracks. There are two common methods you can use to determine whether the radiator cap is bad: performing a visual inspection (to check for damage or wear) or using a cooling system pressure tester. It causes the engine to overheat. A technician uses a special testing device to check the radiator cap pressure. Whats the signs of a bad radiator cap? Fill the radiator with coolant and wait until the coolant starts to bubble or churn. I think that person was thinking thermostat and just said cap. 3G Dodge RAM - General Talk. a bad radiator cap can do this also, the system needs to be under pressure to raise the boiling point of the coolant, if it's not, it won't and it will boil at a relatively low temp. As the bubbles move with the flow of coolant, you hear the movement as a “gurgling”. several things can cause your car to overheat, bad hose, bad thermostat, low coolant, bad radiator cap, bad water pump. If you do not use proper coolant or normal water, it can make coolant bubbling. Therefore, knowing the functions and symptoms of a bad radiator cap is a handy and straightforward DIY maintenance tip that you should pocket to … Drove 1000 miles with the signs of a blown head gasket, white exhaust, bubbling water tank and radiator, losing anti freeze, but my car still runs. ), but the blown head gasket can also cause the engine to overheat. A faulty radiator cap will cause a build-up of pressure inside the tank which may cause cracks and leakage. 137,000 miles. A defective radiator cap will cause engine overheating in a number of ways. Bad quality coolant has iron or salts which can make the head or engine block coolant line worn. Although as simple as can be, just a piece of metal with a gasket. If the cap develops a fault or is replaced with one that’s not compatible with the system, air can get into the system and cause problems. The problem of the radiator fan not working will cause tremendous damage to the engine and thus must receive immediate attention … This doesn't have much of an effect other than when going very slow or parked. That would cause air to be sucked in through that hole, instead of the coolant from the reservoir. Perform a visual inspection : If the cap’s seals are worn or damaged (or the cap is compromised in any way), replace the cap right away. RAY: The other--and more common--cause of this problem, is a bad radiator cap. The radiator cap isn't. However, there’s also the possibility that there is air trapped in the system. The radiator cap could be the cause of coolant reservoir overflow or backup. If you have a bad cap, the coolant will get released, too quickly and cause the reservoir to boil over. Radiator Hose Collapses. You may have a bad cap, if the radiator hose collapses. where exactly is it bubbling from, the hose itself or where it connects. is there fluid under your car? That one I think will be dealer only. When I bled the cooling system, almost an hour there are still bubbles. jkn July 18, 2016, 5:14pm #11 Have the cap checked to see if it is bad. If you’re wondering whether a bad radiator cap can cause overheating, the answer is a definite yes. You ’ re wondering whether a bad radiator cap is located above the fluid level so allowing in! 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