Can an overheat cause oil to thin?

If so could this cause oil to burn off from the dipstick? I was reading some of the other posts and a blown head gasket was said in a majority of them. I'm getting no colored smoke from the exhaust, or anywhere on the engine, just the dipstick.

 

what exactly do you mean by saying the oil is burning off the dipstick?

If you have burnt oil stuck to the dipstick, thats not good.

A blown headgasket would result in steam from the exhaust, or milky oil, or both.

 

yes it can cause the oil to thin and break down.if the dip stick has a milky colour to it,you probably have a blown head gasket

 

My brain is thinking here and it doesent like to. Are you getting smoke like vent from the dipstick and milky oil or just smoke? Some smoke from the dipstick is normal usually means your pcv and breathers arent up to par or the engine is just cooling down. Its normal to pull the dipstick after a run cycle and have smoke come out more like steam... if you have milky oil then you may have a head gasket issue or an intake manifold gasket leak are you adding coolant to the system on a regular basis? More information is needed to help you with this one kinda sounds like there isnt any problems at all.

 

The smoke was venting from the dipstick tube right after the engine got to temp and would continue to smoke until the car was shut off and cooled. Its not a large amount of smoke but it is quite noticeable with the hood popped.

Well, I just replaced ignition coil, cap, rotor and plug wires and also forgot to mention i did a coolant flush last week.

The thermostat is redlining before the fan kicks on, then it cools it back down to somewhere in the 170-180 area. Then it starts to rise again a minute or two later. Doing the ignition work seems to have solved the smoke issue. The timing was waaaaaaaay off. hope it didn't do any damage.

But anyway, the oil is not milky, its either the same color or maybe even a little more transparent if that is any indication of a problem.

 

Just wanted to update everyone. Read through the troubleshooting in the Hayne's manual and determined it was the thermostat. Completely filled/clogged with rusty coolant. I'm beginning to think this was the most neglected car on earth before i bought it. But it runs better than it did, temp still spikes every once in awhile but only to about 220.

 

crankcase venting from dipstick tube is not uncommon . replace PCV valve & filters . good luck .