Possible seized engine...any help MUCH appreciated

Just returned back to Northern Iowa from South Carolinaafter 6 months, went to start my truck and engine seems to be seized. Pulled starter, bench tested, and tested fine. Battery tested fine as well, as its been on a trickle charger in the basement for months. Almost 100% sure the starter teeth are jumping the flywheel teeth making an awful metal scraping noise and engine jumping/shaking badly while turning the key. Did read somewhere that you can use a breaker/cheater bar or such to work the crank back and forth, and someone else recommended pouring marvel mystery oil down in the cylinders and letting sit for a few days.

Truck seemingly ran perfectly fine when parked last October,although I have suspected a head problem for a while as it slowly goes through coolant(no leaks). Also Northern Iowa is bitter cold in the winter with many days below 0 degrees.

Truck is a 1997 Tacoma, 2.7/3RZ with 134,xxx miles on theclock.

MANY THANKS for any help/suggestions in advance!

 

Put it in neutral, and use a cheater bar on the bolt on the harmonic balancer. That will tell you if it is really seized. Now, if it is.....the "Slow Leak" from your coolant may have rusted the rings to the block. So drain the oil and see if there is anti-freeze in it.

 

Pull the spark plugs, inspect then proceed with the above.

 

^^^^Will try all of the information above and report back later with the results.

Thank you gentlemen!

 

If you have a manual trans shoot a little oil in the cylinders and rock the truck back and forth in gear. That might loosen it up.

 

If coolant is getting into the cylinders it could be hydrolocked. Pull the plugs as mentioned then try to turn it over with a breaker bar.

 

I've seen a seized alternator bearing stop an engine in its tracks. I'd remove the belt(s) from the crank pulley and see if that frees it up 1st, then diagnose from there.

 

^^^^^^Many thanks to all members above for the information.^^^^^^

Good news and bad news. Got the crank/harmonic balancer to break loose with a breaker bar thus unseizing the engine. Then got the truck to crank fine, but lots of continuous white smoke out of the tailpipe. Checked oil before cranking and it was over the full mark, but looked ok. Checked oil after 10 minutes and the oil looks like chocolate milk. Guessing a blown head gasket or cracked head, that had possibly started before the winter, but now much worse. Now to research replacing head/head gasket as I will need to do the repair myself(personal first attempt at H/HG replacement).

Many thanks again gentlemen for all of your help!

 

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Remove all the belts and give it a try again.