Crank bolt removal

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RS2000
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Crank bolt removal

Postby RS2000 » Sat Jul 23, 2016 9:19 pm

When removing & replacing crank pulley bolt, should I go to the trouble of making a tool to stop crank rotation, or is it ok just to select 5th gear?

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smy0003
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Re: Crank bolt removal

Postby smy0003 » Sat Jul 23, 2016 9:37 pm

I used 5th and handbrake. Had no issues, but some haven't been as lucky.

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hks_kansei
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Re: Crank bolt removal

Postby hks_kansei » Sat Jul 23, 2016 10:48 pm

5th and handbrake as well.

Just put an extention on the breaker bar for leverage.
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Re: Crank bolt removal

Postby Wuey » Sun Jul 24, 2016 1:06 am

6th gear and foot on brake pedal works for me. However torquing up the bolt to spec in reverse order is a little tricky as the car will still move a little as you tighten up the bolt so the torque figure might not be as accurate. No sign of crank wobbling since I did the timing belt replacement 3.5 years ago.
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Re: Crank bolt removal

Postby Mr Morlock » Sun Jul 24, 2016 12:32 pm

for those that have never experienced in some vehicles the crank bolts can prove extremely difficult to move- sometimes near impossible. The best way is using a holding tool and that way its not going to move. You can buy them at fairly nominal cost and maybe use just once. Or the other methods. The right way is a holding tool.

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Re: Crank bolt removal

Postby a222133 » Sun Jul 24, 2016 6:12 pm

another method to undo even the toughest crank bolt is to use a breaker bar with a short extension tube taped to the end of extension bar [ the extension calculated to hit on the passenger side rail "chassis" an over lap of 12mm is enough ] . Place the bar/ extension at about 3 o'clock and maintain a 90 degree angle between "impact" socket and bar now turn the starter key . I have used this method successfully dozens of times on different vehicles

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smy0003
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Re: Crank bolt removal

Postby smy0003 » Sun Jul 24, 2016 6:14 pm

I'm way too much of a wuss for that method.

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Steampunk
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Re: Crank bolt removal

Postby Steampunk » Sun Jul 24, 2016 10:04 pm

mechanic mate used uber "breaker bar extension" (chain link fence hollow post), he braced it whilst I turned the ignition for a fraction of a section. Bolt loosened after three brief turn-overs.
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JBT
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Re: Crank bolt removal

Postby JBT » Mon Jul 25, 2016 8:48 am

Poor mans' rattle gun method without a rattle gun.

1. Jack front of car
2. Fit socket with a longish breaker bar such that the end of the bar is pointing to the right (as you look at the car from the front) and just above the floor
3. Lower the front of the car until the bar is under a a little tension in the bolt loosening direction
4. Tap (don't belt the daylights out of it) front of socket with a hammer
5. Bolt should loosen after a few taps

This method has worked for me every time.
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Re: Crank bolt removal

Postby Mr Morlock » Fri Jul 29, 2016 8:23 pm

a222133 - thats what mechanics do i.e. using the starter motor. A mate and I could not remove a crank nut and I simply gave it to a mechanic who does it that way when he has to. I had tried breaker bar, and extension and did not get anywhere. Its the shock that breaks the seal. Not sure if MX5s ever get that tight though. I bought a holding tool for the MX5 from USA and it was cheap and its only been used by another guy who was doing a timing belt. Incidentally recently I had the same problem on an inspection plug on a gearbox. I tried everything that I knew and it would not budge. I took it to the local mechanic who I know and he removed it with a special socket ( the mechanics often have these things) - it had like a spiral in it and probably just gets tighter as it turns - he did it first attempt and no charge for me. I used to be able to crack a stock whip though- does that count?

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Re: Crank bolt removal

Postby RS2000 » Fri Jul 29, 2016 10:01 pm

I ended up making a holding tool just for the exercise. The bolt undid without much trouble at all.

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Re: Crank bolt removal

Postby a222133 » Wed Aug 03, 2016 7:46 pm

Mr Morlock . a couple of decades ago when you were cracking whips [ no offence intended ] I also at that time watched a mechanic in a garage crack a crank bolt with this method .

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Re: Crank bolt removal

Postby StanTheMan » Thu Aug 04, 2016 3:00 pm

Try cracking the bolts on the rear wheel hubs.....I had to jump on a meter extension to get it to move after 15 years of not being touched
A friend went to a tyre place and the used a rattle gun ( is that what they call them?) and his came loose in no time.
No chance of using one of those on the crank bolt though. I usually do the ignition trick.
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