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Car Overheating with radiator cap off

I have a 2007 Honda Odyssey touring model. Recently I had it serviced at the Honda dealership. In addition to my requested front end alignment and oil and filter change, they talked me into a radiator flush, fuel inj. service, air filter replacementsand battery service. I drove the car home after wards even filling up with gas before going home to Greeneville, TN. This drive was about 55 miles. I never noticed any problems. The next day, I left for Montghomery AL towing a trailer with a motorcycle trike on it. We stopped for lunch and continued on through Chattyanooga, TN into GA. The car suddenly started making a grinding noise from engine compartment and suddenly white smoke started coming out from the hood. I immediately pulled over and we got out of the car for fear of fire. This was the first time I had any indication of a problem. After a short time, I opened the hood to see what was wrong and noticed that the radiator cap was sitting upside down next to opening. I had the vechile towed to Chattanooga where I was told there was serious damage to the engine. I had them repair it (they were an AAA approved towing and repair shop). I also took pictures of the engine compartment. I went back to the dealership and asked to be reembursed for my expenses and the cost of repairs and the owner refused. He said he didn't believe they left the cap off and since he started out in the service department he didn't believe the car could even go that far without overheating. My question is: Is it possible for a 2007 Honda Odyssey to travel approximately 220 miles over two days before overheating and wrecking the engine if the radiator cap was left off and/or if no fluid was even added and the radiator cap was left off?


  • edited February 2011
    With a full cooling system and no cap, yes, the vehicle could be driven 220 miles.

    With no coolant, I doubt it.

    The question is, why did it overheat?
  • edited February 2011
    I agree with McP that it could have been driven that far wih a full system and the cap off. I think the evidence strongly suggests that they left the cap off. In small claims court you'd probably win.

    The customer should not have to do this, and I'm not suggesting that the fault is in any way yours, but what I do whenever anyone works on my car is double check to the extent possible before paying the bill. I look to be sure fluids ar good, caps are secure, and whatever else might be relevant to the work. I's always prudent to double check.
  • edited February 2011
    I think in overheated because it was under heavier load towing the trailer, and the coolant boils at a lower pressure without the cap on.
  • edited February 2011
    You likely talked to the service manager at the dealership. Very few of these people have much in the line of mechanical abilities and rely on their mouth to get through the day.
    He said he didn't believe they left the cap off. How does he know? He wasn't the one working on the vehicle.

    Yes, it's entirely possible to go that far with the cap loose. At times the cooling system may lose a spoonful of coolant here, a half a cup there, and eventually the coolant level is low enough to cause overheating. When this occurs the loose cap may be blown off.

    Someone screwed up by failing to tighten the radiator cap and they are going into their CYA (cover your axx) mode.
    This guy may claim to have started out in the service dept. but that doesn't mean that he ever had a clue either.

    What would I do? I'd go in and ask to speak to the dealership's owner about this problem. Keep it firmly polite at this point as the owner probably has no inkling about what happened here. Tell the owner you hold them responsible and intend to bring a suit in small claims or district court (depending on the law in your state).

    Just for grins, before approaching the owner you might tell the service manager to his face that in 2 minutes you will be speaking to the owner about this matter. Watch his reaction.
  • edited February 2011
    The "mechanics" left the radiator cap off and the coolant finally boiled away. It is definitely their fault and they should want to pay for the repairs. Telling lies is much more convenient. Your story is perfectly told and the damage happened just the way I think it would. The exact thing would have happened in 1968 when I started my auto repair training and any mechanic knows that it happens almost exactly as it happened to you.
  • edited February 2011
    I believe this car could drive that far without a radiator cap. What was the approximate temperature that you were driving through? As stated previously, you would loose a little bit of fluid at a time, until it did not have enough to circulate. As for getting money out of them, I wish you the best of luck. A friend of mine had a similar issue, with the shop not repairing a belt, but charging for the repair. Belt broke, and engine overheated.
  • edited February 2011
    The cap was off when I opened the hood. It had not blown off because there was no way it could of blown off and landed upside down next to the opening because there was not enough clearance with the hood closed for it to blow off. Also, if that would of happened, I am sure I would of noticed it happening.

    It was the dealership owner that I requested payment from and who told me it couldn't of gone that far and he didn't believe that they did it. He told me to sue him if I wanted to.
  • edited February 2011
    Well, I'd take his advice then.

    Sue 'em.

    You should also send a letter to Honda Corporate. I doubt they'd appreciate it that one of their dealerships is screwing their customers to the point that they register for car sites as "nomorehondas"
  • edited February 2011
    Yes sir t IS possible that you can drive 220 miles and NOT overheat. WHen you added the additional load you got the higher temps. The rad cap has several purposes, one to obviously keep the coolant IN the radiator. It also seals your cooling system which due to physics RAISES the boiling point of your coolant. You suffered a triple or quadruple whammy when you didnt have your cap on.... You probably lost a amount of coolant due to it being off, after that you had less coolant thus lowering your cooling capacity of the rad and also the cap being off lowered the boiling point of your coolant. This coolant loss can also create an air pocket around the water pump not allowing the pump to properly circulate the coolant further exaserbating your cooling woes. Let me know if you need more info. But yes if they left the cap off you will be able to go a while with NO problems. It will take a while and then you will see precisely what you have seen. Hope you didnt warp your cylinder heads.
  • edited February 2011
    Whether the cap was on or loose is actually irrelevant. The bottom line is they screwed up and from the sound of things the owner and service manager are sharing the same bunk bed so as to keep their story straight.

    When coolant heats up it will expand and the cap is designed to maintain pressure on the system to hold that expansion down and raise the boiling point of the coolant. With the cap off the coolant is going to run over in dribs and drabs.
    With the engine cold on your car right now you could remove the rad. cap, start it up and allow it to idle, and soon the coolant will start running over into your driveway. This is true of any car.

    This service manager has no idea what he's talking about (a common malady in their world) and if I were you I would consider talking to an attorney and have the att. fire off a strongly worded letter for a start.
    Also take the advice of Shadowfax and send a politely firm letter to Honda's regional office outlining what happened and your intent to sue the dealer and possibly name corporate Honda as part of that suit.

    Corporate Honda cannot legally make the dealer stand behind this but they can apply some heavy pressure to make things right.
    What a bunch of weasels. Just for hoots, ask the service manager to appear on this forum and try to lay that BS out to some mechanics. The SM is dead wrong and is either lying through his teeth or is an ignorant, incompetent buffoon. The latter I suspect based on the ones I've known.
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