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Is my engine dead?

My car broke down about one week ago. At first the battery light went on, then the engine got real hot so I quickly pulled over and my engine immediately cooled. I didn’t turn off my car because of the battery, but slowly the lights in my car started dying and my engine sounded like it was reving and slowly dying so I turned off my car. It turns out my alternator was busted, but we can’t figure out if my engine is alright without replacing my alternator apparently. Is there anyway I can tell if my engine is alright without replacing my alternator? Do you think my engine is okay considering my it immediately cooled once I pulled over? I would appreciate any advice, since I would love to avoid spending $800 just to find out my engine is dead. The car is a 96 Saab 900 SE. Thanks!

Some more info on the car would be particularly helpful - e.g. how many miles on it? Was the car running normally (and at normal temps) before this one event. Or do you have other reasons to think there are engine problems. A brief overheating is unlikely to have done much damage, but of course the first order of business would be to find out about that problem even before the alternator.

Either way, you can run the car with the dead alternator by using a jump box. You can do that long enough to stick a vacuum gauge on it and look for problems - quick & easy 5 minute view of how the engine is doing.

You can also use a jump box to give the engine enough crank to check the compression.

If a mechanic told you that you need to replace the alternator to check the engine I would get another mechanic.

Is there coolant in the radiator? Not the overflow bottle, the radiator.

The alternator failure, by itself, should not cause the engine to overheat. If, however, the alternator and the water pump are driven by the same belt, and the belt broke when the alternator failed, then there could be engine damage.

You have to determine why the engine overheated before you can even begin to guess about possible damage.

Are you saying it costs $800 to have the alternator replaced? That sounds outrageously high.

My question would be: How do you know that the engine got “real hot”?

I think the engine is probably OK, unless the belt that drives the alternator was slipping and also drives the water pump—in which case the engine could have been damaged.

I think why your engine was reving and dying is as the battery drained, the computer no longer was getting coherent information from the engine sensors with the voltage all out of whack, so it was trying to control the engine with faulty information—so it ended up behaving strangely, until the battery finally got too low to run the ignition system, fuel pump, computer, or all three. As the battery got lower, the gauges may not have been too reliable either–so it may not have been overheating, it may have been a false reading.

I’d just have a mechanic check it out and go from there.

$800 for an alternator?

A rebuilt Bosch alternator for that car is $175 on line.

Most often, the brushes wear out at around 150k-200k miles. A new voltage regulator with new brushes in it is only $30, and if all it needs is brushes, you can get them for $7. You probably need a soldering iron to put the new brushes in your voltage regulator. The voltage regulator attaches to the back of the alternator with a couple of screws. The diagnosis can be tricky, but the parts replacement is all easy do-it-yourself stuff.

It seems an odd that the car overheated at the same time that you lost battery power, and it cooled when you stopped. Cars usually cool better when moving than when stopped. If it overheated because the alternator froze up, and the alternator and it shares a belt with the water pump, so the pump started turning, it would not have cooled when you stopped. Are you sure that it cooled, or did it just stop steaming because it ran completely out of water? What were the indications that the engine was really hot?

You are prudent to question spending money on a 13-year-old Saab if it has seriously overheated. If the belt is turning the water pump, put a known good freshly charged battery in it, top off the radiator with water (not just the reservoir but the radiator) and test it. With a charged battery, it will drive around for an hour or two in the daytime on battery power with no alternator. That will tell you if the engine is seriously damaged.

Anyone who tells me that $800 for an alternator to check the engine is not trust worthy. Get a used one or jump the car, anything. Most likely, the car is fine. Previous posts are valid.

I agree, $800 dollars does seem outrageously high. The overall bill for repairs is as follows:
alternator: $280
tensioner: $65
fan belt: $65
3 rollers: $180
and around 3 hrs of labor: ~$232

I probably should have specified these repairs in my initial engine considering the belt could have some affect on the engine? And I’m not really sure what the rollers and tensioner do.

-Op

The temperature gauge for my engine went very hot in a matter of seconds but immediately cooled once I pulled over. I do need to replace the fan belt, so perhaps that could have affected the engine?

And thanks for all of your help!! -Op

There’s about 115,000 miles on the car and the car had been running completely fine before this incident. I’ll recommend the jump box idea to the mechanic. Any idea why they wouldn’t have suggested this? I would try bringing my car to another mechanic, but unfortunately I’m 3.5 hrs away from where the car broke down and I think the nearest Saab mechanic is 80miles from where I dropped it off; it’d be quite the expensive tow. Thanks for your help-

You can give the engine the “sniff” test. Remove the oil filler cap and put your nose down there and breath in.Does it smell like a road crew is doing some reseal work in there? When oil gets real hot it turns to a asphalt like substance,if your engine got that hot you have trouble.

Okay, this might make sense now. The reason he needs the alternator replaced could be that it froze up and a new one maybe needed just to be able to put on a new fan belt to turn the water pump. The charges look reasonable.