Author Topic: Removing 22mm harmonic balancer bolt (Read 10892 times)

e30boarder · « **on:** October 11, 2010, 12:26:14 PM »

I've been having some difficulty trying to remove the 22mm bolt. I tried using a decent sized breaker bar on it and I just recently tried using a 1/2in impact gun. It still doesnt want to move. The next thing I was thinking about trying was a 3/4in impact gun. My question is, will it snap my crank? I'm always open to other ideas, so any suggestions would help.

DesktopDave · « **Reply #1 on:** October 11, 2010, 02:17:28 PM »

I haven't heard of the crank nose snapping off on BMWs, but I've never taken one off. I have heard of the woodruff key cracking though.

e30boarder · « **Reply #2 on:** October 11, 2010, 03:48:27 PM »

what exactly is the woodruff key? I have the engine completely out. The oil pan and the head are all off. The only thing I'm waiting for is the freakin 22mm bolt. I'm replacing all the sprockets and timing chain components, so i need all that off. A couple pieces broke off the guide rail and were rattling around in the front casing part of the oil pan. I guess I'm pretty fortunate the broken pieces didnt find the crankshaft

nickmpower · « **Reply #3 on:** October 11, 2010, 04:45:57 PM »

what I did was use a huge breaker bar while the engine is on the ground, someone is standing on it, and there is a block of wood in between the crank and block

DesktopDave · « **Reply #4 on:** October 11, 2010, 07:02:49 PM »

The woodruff key is the metal half-moon thing that sits in the crank slot & holds the crank pulley on. I wish I had the motor out of the car for the gasket job I'm contemplating. It's so nice to work standing straight up. However, if it was in the car you could blip the starter to bang it off. If you have a bigger impact wrench I'd go for it.

Good for you that the chain guides held together though. That's the biggest problem on this engine...imagine how much worse it would be if it was a single-row chain!

1991 E30 M42 · « **Reply #5 on:** October 11, 2010, 11:47:19 PM »

I used a 24" breaker bar with a 36" pipe on it every time I did it. from factory thy are torqued to over 200ft/lb and your average impact will not make that regardless of what it is rated for. I tried a brand new $400 ingersol rand titanium 1/2" impact rated at 600+ ft/lb and couldn't break it loose.

nicknikolovski · « **Reply #6 on:** October 12, 2010, 03:52:19 AM »

You need to prevent the crank from turning. I was able to loosen my crank bolt with ease using the flywheel pin. Otherwise remove the starter and place a pry bar against the ring gear and engine block to counter it.

e30boarder · « **Reply #7 on:** October 12, 2010, 09:23:51 AM »

Alright.. i'll start with the impact and if that wont work ill go for the extension on the breaker bar. its at least a 24" breaker bar. i bent the mount the block is on cuz we were torquing that bolt so hard

bmwman91 · « **Reply #8 on:** October 12, 2010, 06:03:29 PM »

Do not use an impact gun. It won't work, and all you'll end up doing is breaking something (probably the impact gun).

Breaking it loose is easy. There are 2 methods that are popular:
1) Get some 1/4" or 1/2" steel plate & drill holes that match the 6 crank pulley holes. Bolt it on there & rest it against the frame on the passenger side (or the AC compressor, but be careful...maybe remove that first). Put your breaker bar on there, maybe with a 4' long piece of steel pipe to help out Y crack it loose.
2) Get a long wrench on there, one long enough to reach over to the frame under the air box. Remove the airbox & put a block of wood in place. Put the wrench on the 22mm bolt head & rest the handle on the wood block. Get in the car & try to start it. The starter should break it loose with the wrench up against the wood block, no problem.

DesktopDave · « **Reply #9 on:** October 12, 2010, 08:01:02 PM »

PO noted the motor is on a stand. That makes this particular job a bit more difficult, I'd figure.

monko141 · « **Reply #10 on:** October 13, 2010, 10:45:12 AM »

Quote from: nickmpower;97322

what I did was use a huge breaker bar while the engine is on the ground, someone is standing on it, and there is a block of wood in between the crank and block

Just about the only way you are going to be able to do it without a crank holding bar. While it's open pull the #4 main and see what shape your crank and thrust bearing are in. Main bearing torque specs are, 20 ft/lbs initial, 56 ft/lbs final. Torque on the new crankshaft bolt is 244ft/lbs

e30boarder · « **Reply #11 on:** October 13, 2010, 11:38:03 AM »

I was hoping I wouldnt have to change the crank bearings. Friday I have about $750 worth of parts for the engine coming in. My old man works at the dealership so I get them at a slight discount. The original list I had put together was just around $1200 so I told the parts guy to tone down the list alittle and focus on timing chain components and piston rings and rod bearings. I still have work to do to the head and a few other odds and ends. Im trying to have the complete build the way I want for about 1500 max.

1991 E30 M42 · « **Reply #12 on:** October 13, 2010, 11:55:04 AM »

If your going to go through all that trouble you should replace the bearings as well, they have always been the failure in the m42's that I've broken.

e30boarder · « **Reply #13 on:** October 13, 2010, 12:05:06 PM »

damn, alright i suppose i could do that. I honestly want to get another 200k out of this motor so if I have to spend alittle extra, im game.

dvmotorsports · « **Reply #14 on:** October 13, 2010, 06:12:53 PM »

I did this on a stand. I locked the FW and then removed the bolt with a breaker bar.