61 replies to this topic

[Guess-Works.com]

This is not far away from the plan, it's a machined unit which screws in, and then has an edge which is stood off from the crank which will 'catch' the flywheel before it dissapears across the workshop...

 

The problem with putting a bolt in loosely is, if there's too much pressure and not enough threads engaged then the bolt can be pushed into the crank totally destroying the thread on both the bolt and crank.

[Dan]

Will you have a Torrington bearing or something on the end of the puller bolt? If it will be pulling with a bolt that is. Because the other problem I can foresee is the puller picking up on the threaded thrust piece and winding it further into the crank. Possibly destroying the threads but certainly making it incredibly difficult to remove at the torque levels some people reach when pulling. What is really needed I think given how much trouble some flywheels give, and this may be what you are looking at, is a hydraulic puller bolt. 10 ton units are quite cheap and give a massive load multiplication.

One thing I have recently found out is that apparently a bolt puller should have a pulling thread of half the diameter of the shaft you are pulling the item off of, and that's for a parallel shaft too. I think the flywheel pullers don't come anywhere near that.

Maybe:  image.jpg   15.77K   41 downloads

[A-Cell]

Dan, John
The old Sykes Pickavant hydraulic tool was fantastic. The hydraulic ram only fitted on Engine out of car. There was a short bolt that could be used with engine on the car and that had a diameter of approximately 25mm.
The factory puller had a bolt of about 3/4 inch with a UNF thread, also a ball bearing was inserted in the end of the bolt. Fixed in position by preening the edge of the hole with centre punch. Presumably the ball bearing sopped the bolt end from distorting and also acting to multiply the effort going into the crank. The bolt was screwed in nearly all the way into the crank, leaving a small gap of about 1/8 inch, plenty of thread engagement. I never had a problem removing older pre-Verto flywheels. Only Verto ones prove a pain.
Also my observations are that the most difficult are the ones that have already had a clutch change in their service history and the flywheel has been refitted without ensuring at the minimum a clean taper, or better a carefully lapped and clean one.

[mk3 Cooper S]

Having suffered most of the above throughout the years I always remove and engine to change the clutch/remove flywheel.

 

Not only does it aide removal but re-assembly.A friend of mine has half a foot due to a flywheel coming loose!!!

[mrducati]

Glad to see it came out. Can't tell from the pic. Are there thread marks on the broken piece where it got stuck. I have a pic of 850 crank that shows thread starts much deeper than where it got stuck. Try crank bolt if you haven't already to see if threads are damaged.

Again glad to see it worked.

I too am so glad it finally came out! There are no treadmarks on teh piece. The crank bolt won't go inn, so there is at least some damage to the treads. If I put a finger inside it doesn't feel like a lot of damage, but I guess it's hard to tell this way.

 

I've seen this before, and I've also split one of the trust blocks in two when under load...

 

Which is why, this part of the puller is also being looked...

 

Now the question is... have your ordered the right tap for the crankshaft ????

What do you mean by "this part of the puller is also being looked"?  Sorry, my English might be inadequate. Do you mean it is a problem area that is looked at?

 

The tap i ordered is 5/8 Witworth. I really hope I'll be able to fix the treads!

 

Having suffered most of the above throughout the years I always remove and engine to change the clutch/remove flywheel.

 

Not only does it aide removal but re-assembly.A friend of mine has half a foot due to a flywheel coming loose!!!

Sorry to hear about you friend! That is frightening! Did it happen during disasembly or did it come loose when the engine was running?

I am not sure if I would have been able to remove the flywheel unless I had a enginestand that was bolted to the floor. So great was the force needed to get it loose that, despite using a long lazy-mans-arm, I had a sore back and arm the day after. I think I would just have pulled the enginestand around the garagefloor.

But to get that piece out, it would definately have been easier with the engine out.

[mk3 Cooper S]

Yep, came loose whilst running, during a gearchange I think?

 

Glad you are sorted out now. Persistance has paid off.

[Dan]

  If you ordered a standard ⅝ Whit tap it will be 18 tpi which is not right.  This is a custom thread at ⅝ Whit x 16 threads per inch.

[mrducati]

If you ordered a standard ⅝ Whit tap it will be 18 tpi which is not right. This is a custom thread at ⅝ Whit x 16 threads per inch.

ARGH! How much trouble is this going to give me! I had planned to do this clutch-change over a weekend, but that is now 14 days ago! Well, as you understand, it is the standard 5/8 Witworth I've ordered. Bugger!

[Dan]

  The right one is available off the shelf at various Mini specialists and Guess Works might still have some.  It will be cheaper and much quicker for you to get one delivered than to get one made locally.

 

  For example, part No. TOOL20 at Mini Spares.

Edited by Dan, 14 February 2014 - 05:52 PM.

[mrducati]

Thanks Dan! It is now ordered. Express delivery. Can't wait to finish this project!

[Guess-Works.com]

Here's a bit of a sneak preview....

 

 DSC_0177.jpg   44.21K   30 downloads

 

And as you have said, the insert screw has a ball bearing in the end which the puller pushes on.

Edited by Guess-Works.com, 14 February 2014 - 07:43 PM.

[tsumini]

Thanks Dan! It is now ordered. Express delivery. Can't wait to finish this project!

May want to check threads of the tap with your flywheel bolt to make sure they match before chasing threads. Just a precaution.

[Carlos W]

Its probably damaged the start of the thread so you can't get the bolt to engage!

Hopefully a quick clean up and all will be well

[mrducati]

Now I have got the treads cleaned up with the tap I ordered form Minispares. I am confident I hit the treads square because it became easyer and easyer to turn the tap. I mounted the clutch back together using Locktite on the flywheel-bolt to compensate for any damaged treads. Now I just need to mount up the rest of the components, and I can test my new clutch. Hopefully it will work!

[Carlos W]

Now I have got the treads cleaned up with the tap I ordered form Minispares. I am confident I hit the treads square because it became easyer and easyer to turn the tap. I mounted the clutch back together using Locktite on the flywheel-bolt to compensate for any damaged treads. Now I just need to mount up the rest of the components, and I can test my new clutch. Hopefully it will work!

 

Good luck, you have the patience of a saint! 

 

I would've got annoyed and broken it well and truly!