Engine Drivetrain 1st Gen Cooper S Most liked posts in thread: Crank Pulley Replacement - Discussion Thread

That's exactly how I installed my M7 pulley. 20 minutes in the oven then slip it on and torque it down.

 

If you're going to slip it on by hand, make sure you're wearing gloves. =)

Thanks for consolidating all the info. I was rooting around the engine and discovered the seal leaking, so I'm going to pull my ATI pulley and replace the seal. I've learned that dirt doesn't naturally stick to an engine; it's usually the sign of an oil leak.

 

I've had the front of my car apart for a few weeks now, and in the course of rooting around I discovered the crank pulley seal was leaking. I didn't take any pictures, but I figured I'd share my notes here, because removal of the ATI pulley is a little different than the stock pulley.

First off, I discovered the leak because the area around the pulley was filthy. The side of the timing case was covered in that dirt/oil sludge. It was all under the idler pulley, too.

To remove the pulley, you'll need the following items:
5/16" 12pt socket (mine is 1/4" drive, so I needed a 1/4" to 3/8" drive socket, too)
harmonic balancer puller (aka 3-bolt puller)
3x 4.5" 5/16-18 bolts (usually comes with the puller)
3/8" drive torque wrench
Blue loctite (#242, removable)
New center bolt (recommended)
New crank pulley gasket, MINI part # 11 11 1 485 171
Small screw driver
Hammer
block of wood

Loosen the center bolt with an impact gun or figure out a way to hold the pulley still. You can brace a big screwdriver on the three 12pt bolts, too. My ATI pulley came with a different bolt with a big Allen head and a washer. I saved the bolt and here, screwed it into the pulley hand tight. The tip of the puller seats better on this bolt than the stock one. If you're using the stock bolt, loosen the bolt several turns but not all the way.

Remove the three 12pt bolts (don't touch the 6 torx flat head bolts). Line up your puller and screw in the longer bolts. I had to rotate the pulley a bit so the puller didn't hit the unit body on the way out. Twist the center screw on the puller and start to pull the pulley off. At some point, the pulley will hit the center bolt. Back the center screw off and loosen the bolt a bit more. Repeat till the pulley comes off.

To remove the old seal, take a small screwdriver and a hammer. The rubber gasket has a couple metal rings inside, so you want to bend the outer ring into a pac-man shape so you can pry it out. Hammer the edge of the gasket, being careful not to score the timing case. Pry out the gasket carefully. Coat the center of the seal with a bit of bearing grease and start it in by hand. Here, you can tap it in gently with a 1/4" drive extension and small hammer, working it in slowly and evenly by tapping in a star pattern. I had a 12pt 30mm axle nut socket for a BMW rear axle that worked perfectly as a drift. Slow and steady, tap tap tap around the socket, until the gasket is flush with the timing case. Wipe off any excess grease and dirt.

To reinstall the pulley, heat per above directions. I turned the oven to 250*F and baked the pulley for about 10-15 min. My oven thermometer pegged the pulley at about 150*F. With gloves, it went on the tip of the crank shaft but didn't slide on. I had a helper use a hammer and a block of wood to seat the pulley better. Then I put a couple washers on the stock crank pulley bolt and drove it on with an impact gun. Remove the bolt, remove the washers, add blue (removable) loctite, and screw back in. Use the three long bolts, a big screwdriver, and a helper to hold the pulley while you torque the bolt to 85 ft-lbs. Wait for the pulley to cool (an hour or two, or lunch and a beer), and drive the three original 12pt bolts back in with a dab of blue loctite. Brace the pulley and torque each bolt to 30 ft-lbs.


Thanks to my dad, who insists this is the same way to do it on a Chevy small block, and to Dan Zipkin at Flow MINI.

 

Thanks. When I removed the pulley, mine was very clearly dripping oil down the timing case cover - I wish I had taken a picture. If it looks dry, don't even bother.

 

So, i think i've made a terrible mistake. While getting ready to remove the OEM damper, I snapped one of the 3 puller bolts off inside the OEM damper. Lets not talk about how....the hardware was used and in awful condition, but mostly I absent-mindedly went a little too far.

Anyway. There's maybe 1/8th of an inch hanging out, and if i can find some vice grips I might be able to get it out. But in the meantime, is there anything else I can do? I just need to get this damn OEM pulley off! I don't think 2 out of 3 bolts would get it off...would it? I'm afraid I'd just break the other 2 bolts.

Oh and I do have 1 back up bolt to use to replace the broken one...as long as I can get it out.

Halp!

 

One thought before you mess up the threads on the broken bolt is if there are enough threads exposed, such as three, maybe you can thread a coupler onto the bolt and then thread another bolt into the coupler to give the puller something to grab onto. The hard part would be finding a metric thread coupler at a local hardware store.
Here is a link to what I am thinking of:
McMaster-Carr

Another thought would be to drill the broken bolt, tap threads into the bolt and screw in a small screw that at least the puller can pull on. But you can not drill the hole too large or it will probably rip up the broken bolt. Might work if the pulley is not too stuck on the shaft.

I do not think that using the puller on just two bolt will work but if all else fails it might be worth a try.

 

Got it out with a set of vice grips. Phew!

Going to the hardware store tomorrow to get better hardware.

 

Great. Glad you got the bolt out the easy way.
New hardware sounds like a great idea.

 

Also popping puller bolts

This my second day trying to remove the crank pulley from my '03 S. Now the bolts screwed into the crank for the puller use are starting to pop out. I keep tightening them, but after a couple more turns on the puller, one pops out. The threads on the bolt look OK, but I fear the threads in the pulley are stripping. Any suggestions on getting this sucker out?

BTW agranger, the removal thread was excellent.

Thanks.

 

A couple thoughts.
First I have a dumb question/thought but is your configuration correct to pull the pulley off? I ask because I have read where others have made a mistake trying to pull the pulley off. Make sure you are not pushing against the pulley with the center puller bolt at the same time trying to pull with the three small bolts. The center bolt needs to push against something other than the pulley such as a partially unthreaded crank bolt. If using a partially unthreaded crank bolt to push against you need to make sure the pulley has not moved enough to be hitting the crank bolt, if so you need to unthread the crank bolt a little more.

Second dumb question. Are you using the correct diameter and pitch bolts to go into the holes? Maybe you have a slightly different diameter or pitch bolt that seems to thread into the hole but is really not.

If you really have stripped out the threads in the crank pulley the hole, you might need to rethread the hole with a slightly larger size thread or at least different thread pitch. The new threads could even be standard threads instead of metric because it is probably easier to find a standard tap. Just make sure you get a new bolt the same diameter/pitch as what you tap the hole.

 

With me there are no dumb questions.

I'm not using an unthreaded crank bolt, just the tapered end of the pulling tool. If I understand you correctly, I need to insert the crank bolt, but not all the way. I then put the tapered end of the pulling tool on the crank bolt and go at it again?

Yep, I'm using the correct diameter bolts. I have a lot of pressure before they pop.

I may have to rethread at least 1 thread after this latest pop.

I'm off to try the bolt.

THANKS

 

You're sure right about the pressure, quikmni. Using the bolt did the trick, but I still needed to re-thread one hole. However, I now have no more threads on the bolt and the pulley is not quite out. Do I get a longer bolt or can I pry the pulley off?

 

My ATI replacement pulley came with a longer bolt so I used that bolt. Did your replacement pulley come with another bolt? Otherwise you might be able to gently pry the pulley off. You might be able to use the puller to pry on and wiggle the pulley off.

 

I went with the Mini pulley, so didn't get a longer bolt. However, I have a longer bolt, but a smaller thread. I'll try that.

For the replacement, if it doesn't go on I guess I will heat it like everyone has mentioned for the ATI pulley. Now I wish I would have waited and gotten it. Oh well.

 

All right ! Glad you finally got the pulley off and the new one installed.

 

After seeing some so-so install notes on other sites, I found your how-to incredible! Great job, it helped me very much!! http://www.motoringalliance.com/forums/images/smilies/biggrin5.gif

Kevin
Muscle Shoals, AL