Crankshaft bolt stuck, help!
 

In the process of a timing belt change on a friends stock 94 and I can't seem to crack the 21mm crankshaft bolt lose. Every time I've done it on my car it has recently been done before (new to car engines lol).

I've been using a 2 ft breaker bar with a 3 ft jack handle around it. Tried it when its in 1st, reverse, and 5th. Tried pushing from the top, pulling from the bottom. Tried some wd40 on it and tapped the bolt to make it vibrate. None of this is working, haven't tried an impact gun, I'd need a bigger one than what I have but I would also have to undo the swaybar and take out the radiator and fans and somehow wiggle it around the A/C lines.

Story on the car: has 156k miles, from Ohio, other nuts/bolts have been a pita to get off and some have snapped off from rust issues. Two owner car, stayed in the family. The lady selling the car said the car has never had the timing belt changed ever, I don't know how that's possible, really. By the looks of the belt it had to be changed sometime before she got the car from her brother, no missing teeth, no cranks, no signs of 156k mile wear either.

I'm stumped, I've never had a crankshaft bolt on any miata or honda I've had be this pita :(

I used my impact, but haven't I read something about wedging the bar and tapping the starter?

i usually leave the rear tires on the ground, chocks in front of rear tires, 5th gear, parking brake on. if still not enough use a cheater pipe

The 3' Jack handle is being used as a cheater bar. Rotate it till it's against the ground and crank the engine BRIEFLY. Be smart, double and triple check that's it's on the correct side, and don't let anyone stand close when you do it.

+1

I didn't have to do it to mine but seen it done before. Mine came out with a breaker bar and in gear.

use the starter motor dude duh works everytime

I'll have to do this, thought about it before but already had everything apart and kinda looked over it.

If the engine and bolt rotate clockwise then I'd need to put the cheater bar on the right side on the ground, correct? So when the bolt rotates to the right the socket and cheater bar will stop it and push it to the left.

It helped when I typed it out :-D

Right side when looking at the front of the motor, driver's side of the car, yes.

the starter method worked on my car last spring. No harm done. :)

Just did the starter motor trick on my dad's lexus a couple weeks ago - impact wasn't strong enough (Cheap Autozone impact gun). Worked great.

One of the four 10 mm bolts that hold the crankshaft pulley broke, was torque'n them down to 12 ft-lbs (which is spec). I've never had a car give me this much trouble. Although it was from the north and had lots of rust, I guess I've been spoiled with TN cars :(

The stock bolts are pretty damn weak i went to fastenal and got a bunch of allen head super strong 10 mm bolts to replace them all after my first set failed.

So, did the good ole turn engine with breaker bar trick and it was a no go.

My friend made an executive decision and took his car to a local shop.

Turns out the bolt had fused and basically welded to the engine. So the bolt really was stuck lol.

If its not breaking loose, you just aren't putting enough ass into it. Mine took me (180lb) hanging on a 3/4'' breaker bar with 2ft handle and a 4ft heavy pipe. When it broke free you could probably hear the pop 2 miles away. Friction is a bitch. If you don't have the required ass, use the starter like already stated.

n/m, just saw above post. Then what did the shop do?

He has two options he's considering.

Pull the engine, extract the bolt, drill/tap it if need be and put it back in.

Or buy a new crate motor and drop it in, something with lower miles.

wait so the shop couldn't get it out either?
starter method didn't work?

Except when a dumbass automaker decides to rotate their engines backwards, like Honda. Starter method is fine for Miatas, though. Hondas are what caused me to not bother with starters and just use an impact on any vehicle. Well, that plus the fact that most people don't want me getting my greasy ass in the driver seat in the middle of a job. Once I had an impact wrench (525 ft-lb Kobalt) let me down on a crank bolt due to some previous worker using a large quantity of Loctite, I just took it as an excuse to buy a better impact wrench (Aircat 1100K).

The shop broke the head of the bolt off, most of the bolt is still stuck in the crank lol.

well if they broke it then they should fix it imo. It wasnt broke when you brought it to them so its there fault plain and simple.