Edmunds Answers

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  • avatar zaken1 03/05/11 3:12 am PST

    It also sounds to me like you blew a head gasket. When a head gasket blows; it often does not cause contamination of the oil. Sometimes it causes a compression leak between 2 adjacent cylinders; other times it causes coolant to be sucked into the cylinders; or compression pressure to get into the radiator; and other times it causes coolant and oil to mix. It all demends on where and how much the head warped. If your spark plugs are wet; this means that coolant is getting into the combustion chambers. When this happens; if you ever get the engine to start; it will blow large amounts of white smoke (actually steam from vaporized coolant) out the exhaust.

    There are two things which could have caused overheating without the gauge showing it. One would be that the coolant level in the radiator had gone down; but you didn't check the level directly at the radiator, and only checked and refilled the level in the reservoir bottle. When a head gasket leaks; the air pumped into the radiator through the leak will break the siphon action between the radiator and the overflow bottle. If that happens, the coolant level in the radiator will drop, while the level in the overflow bottle does not go down or only drops slightly. If the coolant level in the radiator gets low enough; it will drop below the location of the coolant temperature sensor in the engine; which stops the temperature gauge from showing it when the engine heats up.

    The other cause for an engine overheating would be that the electric radiator fan stopped coming on when the temperature got hot. This can be caused by a defective thermal fan switch, or a defective radiator fan relay. Once in a while; it can be caused by a defective fan motor; but that is much less common than the fan switch or the fan relay.

    A long shot; but something I still need to mention, is that I have repeatedly seen situations where the use of Sea Foam wipes out a set of spark plugs and stops the engine from running. When this happens; the plugs may become wet.

    Since you apparently let the motor run for an hour while the vehicle was not moving; the abnormally light load under this conditon could have created an excessivly lean mixture condition which may have caused the engine to become hotter than normal; but not necessarily to have overheated. If the Sea Foam wiped out the plugs at that time; it would create the illusion that the engine had become damaged enough to not run any longer. Because this is a very real possibility; I would remove the radiator cap when the motor is cold and check the coolant level. If the radiator is full; I would let go of the head gasket theory for now; and buy a flexible ratchet, a 5/8" magnetic spark plug socket, and some wobble extensions; and replace all the spark plugs with either a new set of Champion # 3031 Platinum Power, gapped at .050"; or Bosch # 4307 Platinum + 2, or Bosch # 4479 Platinum + 4 (these particular Bosch plugs do not have an adjustable gap). I would also recommend replacing the fuel filter, checking and replacing the air filter if it doesn't pass light easily, and thoroughly cleaning the idle air control valve and the throttle body. I would also install a set of new Borg Warner spark plug wires, if the wires have not been changed in the last 3 years. Be sure to only remove and replace one wire at a time; in order to prevent installing a wire in the wrong position.

Answers

  • zaken1 03/05/11 3:12 am PST

    It also sounds to me like you blew a head gasket. When a head gasket blows; it often does not cause contamination of the oil. Sometimes it causes a compression leak between 2 adjacent cylinders; other times it causes coolant to be sucked into the cylinders; or compression pressure to get into the radiator; and other times it causes coolant and oil to mix. It all demends on where and how much the head warped. If your spark plugs are wet; this means that coolant is getting into the combustion chambers. When this happens; if you ever get the engine to start; it will blow large amounts of white smoke (actually steam from vaporized coolant) out the exhaust.

    There are two things which could have caused overheating without the gauge showing it. One would be that the coolant level in the radiator had gone down; but you didn't check the level directly at the radiator, and only checked and refilled the level in the reservoir bottle. When a head gasket leaks; the air pumped into the radiator through the leak will break the siphon action between the radiator and the overflow bottle. If that happens, the coolant level in the radiator will drop, while the level in the overflow bottle does not go down or only drops slightly. If the coolant level in the radiator gets low enough; it will drop below the location of the coolant temperature sensor in the engine; which stops the temperature gauge from showing it when the engine heats up.

    The other cause for an engine overheating would be that the electric radiator fan stopped coming on when the temperature got hot. This can be caused by a defective thermal fan switch, or a defective radiator fan relay. Once in a while; it can be caused by a defective fan motor; but that is much less common than the fan switch or the fan relay.

    A long shot; but something I still need to mention, is that I have repeatedly seen situations where the use of Sea Foam wipes out a set of spark plugs and stops the engine from running. When this happens; the plugs may become wet.

    Since you apparently let the motor run for an hour while the vehicle was not moving; the abnormally light load under this conditon could have created an excessivly lean mixture condition which may have caused the engine to become hotter than normal; but not necessarily to have overheated. If the Sea Foam wiped out the plugs at that time; it would create the illusion that the engine had become damaged enough to not run any longer. Because this is a very real possibility; I would remove the radiator cap when the motor is cold and check the coolant level. If the radiator is full; I would let go of the head gasket theory for now; and buy a flexible ratchet, a 5/8" magnetic spark plug socket, and some wobble extensions; and replace all the spark plugs with either a new set of Champion # 3031 Platinum Power, gapped at .050"; or Bosch # 4307 Platinum + 2, or Bosch # 4479 Platinum + 4 (these particular Bosch plugs do not have an adjustable gap). I would also recommend replacing the fuel filter, checking and replacing the air filter if it doesn't pass light easily, and thoroughly cleaning the idle air control valve and the throttle body. I would also install a set of new Borg Warner spark plug wires, if the wires have not been changed in the last 3 years. Be sure to only remove and replace one wire at a time; in order to prevent installing a wire in the wrong position.

  • patrick88 03/06/11 5:46 pm PST

    OOOPSS ZAKEN1, meant to give a thumbs up but hit the the thumbs down button!!! Sorry..... one of those days!

  • Stever@Edmunds 03/06/11 6:27 pm PST

    You can reply in this thread by clicking the Answer this Question button and that will help keep all the information in one spot. Thanks!

  • zaken1 03/06/11 7:53 pm PST

    Thank you for the "best answer" vote and the thumbs up. But I need to tell you that any additional questions or feedback about this topic can ONLY be posted in this thread (by clicking the "answer this question" button) If you try to do it by opening a new question (like you just did); that message will not get through; even when the original question has been closed.

    I just wasted a half hour researching and responding to the new question you posted in the wrong place, because I (apparently incorrectly) believed that since the original question had been closed, it was then OK for you to have posted your additional feedback as a different topic; only to be rudely surprised when I tried to post the response, and found that what I wrote was suddenly pulled out from under me.

    I wonder whether Steve even knew that your original question had been closed; or whether having known that would have made any difference in what he did?

    All I can say is that this kind of thing does not have to happen; but when the people in power refuse to address the problems in their system; it turns off those of us who have contributed our sweat, time and caring to build this site into what it now is. And that's no way to encourage loyalty in a mostly volunteer community.


  • zaken1 03/06/11 10:37 pm PST

    The plug gap closing up worries me; this usually happens if the engine has gone into detonation; which can be caused either by over advanced ignition timing, or by an excessively lean fuel mixture, or by spark plugs of too hot a heat range. If you just put the same parts back into it and don't address the cause of the plug gap closing; this will probably repeat itself.

    There are three different V-6s used in this vehicle; a 3.0 and two 3.3s. The 3.0 takes a colder spark plug than the 3.3s. If someone mistakenly used the 3.3 plugs in the 3.0 motor; they might have caused the motor to go into detonation and then have the gap close up. Since the 3.0 is the only one of those engines that has a disributor; it is easy to tell the difference in the engines. Also; the 3.3 plugs take a 5/8" hex socket; while the 3.0 plugs take a 13/16" hex socket.

    The hose that goes to the firewall at the rear of the motor connects to one of the heater core spigots. There should also be another hose from the second heater core spigot on the firewall; which goes to a spigot on or near the water pump. That hose should also be carefully checked for leaks or signs of weakness; as it is likely the same age as the other one.

    The reason that coolant ran out of the hose at the rear of the motor after you flushed the radiator is that there is a thermostat in the elbow where the top radiator hose attaches to the motor. This thermostat will be closed when the motor is cool; which prevents the flow of water or coolant through the engine block and head. This is why it is necessary to remove the thermostat in order to completely flush the cooling system.

    The cylinders on this motor are numbered starting from the fan belt end (passenger side of motor) and going to the transmission end (driver's side of motor). The cylinders on the rear bank (closest to the firewall) are numbered 2-4-6. The cylinders on the front bank (closest to the radiator) are numbered 1-3-5.

    If your motor has a distributor; the order of the plug wires in the cap is NOT THE SAME AS THE FIRING ORDER, due to the very unusual construction of the internal conductors in the cap. If you look at the cap from a position where the two cap hold down screws are at 9 and 3 o'clock position; the # 1 cylinder plug wire should be in the 11 o'clock position. The order of the wires proceeds counterclockwise from there, and is 1-3-5-4-6-2.

    If your motor is one of the 3.3 liter OHV units; there will not be a distributor, and instead there will be a coil with 6 plug wire terminals on top. If you look at the coil from an angle where the plastic low voltage harness plug is on your side of the coil; the order of the plug wires will be as shown below:


    3-1-5
    6-4-2
    plug

    You are correct that the pistons cannot be loose. The ticking noise may come from air in the hydraulic valve lifters, or from lack of oil to the valve gear. It also can come from sticking valve stems, from a bent valve, or from a spark jumping from a badly connected or damaged plug wire.

    I hope this clears up the confusion.

  • skyrods 03/15/11 1:47 pm PST

    Thanks for your response! Figured out the spark plug wiring order(its a 3.0), and am planning to cut out a section of the coolant hoses running to back and replace. Still not sure why all of this happened, am hoping its the lean fuel mixture you mentioned. If I can get away with gasket sealer and new plugs, this will actually have been worth my time! Thanks for your response again, its been quite helpful.

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