Coolant system issues- ripped off

There is a simple chemical test to check for a leaking cylinder head gasket, but it is not foolproof. Nothing you have shared suggests there was an intent to defraud. In fact, if you look at this from the mechanic's point of view, they are so fed up with being accused of selling parts and services that are not needed, and they are accused of not selling enough parts and services when another problem appears weeks later.

Cooling systems have pressure relief valves built into their radiator caps. When a radiator is found to be cracked, that was caused probably ninety percent of the time by a leaking head gasket. Combustion gases get pushed into the cooling system faster than they can be released through the relief valve. That gets worse at higher engine speeds when you are on the highway. If you suspected the head gasket as the cause, you should have insisted on that chemical test, and on knowing the results. If they did that test and it came back negative, what would you have done had they try to sell you a head gasket job? You would probably be one the customers who assume they are selling you unneeded repairs. By your own observation, the engine was running fine for days with the new radiator. Logic dictates if there was an underlying problem, the new radiator would have been damaged right away, or there would be other symptoms. None of that happened, so why would you expect the mechanic to dig further, when time is money?

The brake job is not relevant to this story. It is part of regular maintenance, regardless of the car's age, just like the cost of gas and oil. To find the need for this service suggests they went beyond what was expected, to look out for you. Some front brakes are easy to check for wear, so they can inform you. Only shoddy mechanics would not bother to do that simple task for you. You have to wonder what other normal maintenance items have been ignored that they have no way of knowing about.

Determining the cause of the water pump failure is difficult without doing an autopsy on it. Excessive pressure in the cooling system from the leaking head gasket could have stressed the rubber lip seal that is already old and hardened. A corroded sealing surface the lip seal rides on is commonly caused when the antifreeze is not changed every two years. The corrosion inhibitors and water pump lubricant wear out in about two years, then acids normally form in the coolant. That acid attacks cylinder head gaskets too. These failures could all be related, but with the age, and the mileage you listed, this type of failure is not uncommon. Multiple related failures like this happen all the time. Imagine if your mechanic had said, "besides the radiator, I suggest we replace the non-leaking, properly-working water pump at the same time". You would have accused him of selling unneeded parts. What experienced mechanics who have been caught in these situations before would likely have done would be to explain better the possible causes of this trouble, and the additional parts that could fail later, but most of them are not psychic. They also run into customers who become overwhelmed with too much information, and they cannot determine what is relevant to their car this time. This problem of additional parts failures days or weeks later is real common in brake systems and electrical systems. With many parts, including water pumps, they are about to fail within the next few weeks or months on their own, but something happens earlier that stresses that part and simply hurries up that failure. You should have had some warning before the engine overheated, but even with no symptoms, a sudden, catastrophic failure of the water pump points to it being stressed during the original overheating. It just did not fail because the radiator cracked first, removing the pressure in the system that would have pushed the seal out in the water pump.

For some reason, it is only mechanics we expect to make a perfect diagnosis right away, every time, otherwise they are incompetent or out to defraud. Why do we give doctors a pass when we have to go back four or five times before they get it right, and that is perfectly normal and acceptable? Doctors perform all kinds of tests we feel are unnecessary to fend off potential lawsuits. Mechanics are accused of the same thing when they know what tests have value, but we complain so much that they avoid doing anything that might be seen as unnecessary. Now you are complaining that they did not do enough? How would you feel if they spent an hour doing all kinds of tests that led to no diagnosis? You only value the one test out of dozens that finally provide an answer.

It seems to me your biggest complaint has to do with the age and value of the car, but that is totally irrelevant unless you are spending money to fix up a car to sell. A gallon of gas costs the same whether the car is a year old or twenty years old. A brake job costs the same for both cars. Same with a head gasket. The issue is with higher age and mileage, you will be needing more of those repairs. If you plan on keeping a car that needs an expensive repair, the age and value are more or less irrelevant. I understand that old cars need more of these repairs, but by your own observation, you "never had problems with this car until now", so there is little reason to expect more large repairs any time soon. I have a four-year-old truck and my daily-driver is a twenty four year-old minivan. If I had to stick $2000.00 into a major repair, I would be more willing to do that to the old, reliable minivan, even though it is not worth that much if I were to try to sell it.

I have had students who were spending around $800.00 on repairs every six months, and they grew up thinking that was normal. With that as a benchmark, if you spent next to nothing on repairs and maintenance for many years, you are still way ahead of those kids. My opinion is if you like your car otherwise, pay for the big repair now instead of lots of little repairs on a newer car.

Once you mentioned the timing belt, I had a much better feeling about your mechanic. Normally that is seen the other way. Most commonly the timing belt fails due to neglect, then the mechanic wants to sell you a new water pump at the same time, and that is when uninformed people complain. In fact, to do otherwise would be like buying an expensive pair of new shoes, and insisting on using old, worn out shoe laces. The majority of import engines are of the "interference" design, which means if the timing belt breaks or the water pump fails, valves will be bent. That requires the same head gasket job plus a valve job, so the cost is more than doubled. Every conscientious mechanic who has your best interest at heart is going to want to replace the water pump and the timing belt together. Either one is a big job in itself, and they do not want to do those twice. There were two different engines available for your model. Both run the water pump off the timing belt, so to replace the pump, the belt must be removed. It would be foolish to put an old, worn belt back on when a new one is not very expensive, and it insures the quality of the repair.

To address your concern of other engine damage, the biggest red flag is when the heater started blowing cold air, a warning light turned on, and you drove it another fifteen miles. That was an indication the coolant had leaked out enough that could not circulate to the heater core in the dash. That happens before it gets low enough to overheat the engine. That is exactly how I ruined my older 1988 minivan. That damaged the head gasket, and things went downhill from there. The engine lasted another two weeks, only because I forced it to keep going. The good news for you is that damage is usually limited to the cylinder head and gasket. During the head gasket repair, it is standard practice to check the cylinder head to be sure it is not warped. Beyond that, nothing comes to mind that you need to be especially worried about.

Every leaking head gasket starts out as a very small, slow leak with no noticeable symptoms. That can go on for weeks in some cases, but the point is it takes some time to progress to a major failure with catastrophic symptoms. The clincher was the melted coolant reservoir. Coolant is supposed to get to 200 degrees, and that is not nearly hot enough to melt the reservoir. We can determine hot combustion gases suddenly started getting pushed into the cooling system fast enough to make it that far and do that damage. Had your mechanic seen that during your first visit, he would have no alternative but to condemn the head gasket.

Your circumstances are unfortunate, but nothing you shared so far sounds like you got ripped off. People in this industry are well-known to have real good communication skills, . . . among themselves, but not with their customers. That is worse today when cars are way too unnecessarily-complicated for owners to do their own repairs. We do not understand them like they did just a few decades ago. Just like with doctors, accountants, carpenters, and bakers, mechanics speak their own language. Just because we do not understand them all the time does not mean they are out to get us.