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Confuseddd

So I was checking oil in my 95 Astro when putting the dipstick back in was a lot of tension and the alternator turned over and started smoking and dip stick got super hot out of no where

What?? I can not see how that happened. Okay, some dipsticks have to be put back in, in the very same orientation as removed. But I see no way you could have shorted out something that would cause the alternator to turn over.
Mechanics/engineers, please educate me. I am limited to knowing DC motors can be generators, but alternators be motors?

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if you missed the dipstick tube, depending on where your starter and dipstick tube are, I could see this potentially hitting the starter wires and a ground, and engaging the starter solenoid- turning the engine over. (this could also happen if you have a two piece dipstick tube that has come apart.)

in fact, that is about the only thing I could see happening here to cause this as you describe. I look for other input. :slight_smile:

It’s a one piece no holes anything I made sure all wires where off of the dipstick just incase and they are I’ve had this van for years done all my own work and this has never happened with any of my cars so yeah I’ve met problem couldn’t figure out

some chevys have a bracket that holds the dipstick in place that uses a big bolt close to the front cyl head bolts. i had to wrestle the tube out of the block when i pulled the heads. sometimes it does not come out of the block due to rust. maybe the bottom of the tube is rusted and the dipstick actually did not go into the block and poked down to the starter area? pretty slim chance though.

You shorted an electrical connection. I’m guessing you hit the positive lead on the alternator (or starter) and something metal on the car. That pumped the battery’s output through your dipstick which would indeed make it hot, and make the oil on it smoke.

There’s nothing else on a non-running car that would heat the dipstick up like that, and even if it were running I don’t think it’d heat it up that fast.

How would I do that when I was putting the dipstick back in the tube

You missed. :wink:

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Make sure the dip stick tube isn’t broken at the bottom.

Because if it is, you can put the dip stick in the tube, but it doesn’t mean it’s going to go into the engine.

Tester