15 replies to this topic

[Bell-nose]

Hi,

I have damaged the thread at the clutch end of the crankshaft.

(If I ever get the clutch off which feels like its never going to happen) is it possible to repair the thread in the crankshaft or am I totally ......erm screwed.

If so how and will i need to take the crank out as the engine is in great condition.

Thanks,

[Dusky]

How hard and deep is it damaged? Guessworks lends a tap.
http://www.guess-wor...play.htm?id=494

[carbon]

This item from Guessworks may also be useful...

Heavy Duty "Gerrof ya b'stard" Flywheel Puller
^GW-HDFP

Link: http://www.guess-wor...play.htm?id=501

[mini-mad-mark]

If you just need to clean out the thread you can buy a tap here:

 

http://www.tracytool...product_id=1108

 

£10 plus p&p and an extra £5 will get it to you next day shipping if you're in a rush (for carbon steel probably good enough for a clean out of an existing thread)

 

A plug or bottoming tap is probably best for going into blind holes like the crankshaft

 

Note my previous post on this subject - the correct tap/thread is 5/8" x 16 whitform (whitworth) special

 

To translate in case you are not aware; 5/8" is the major diameter (the "size") and 16 is the number of threads per inch (TPI) which is a special in this case, as a standard 5/8 whitworth thread would be 11 TPI

 

Whitworth means a specific thread form or "shape", different in detail to other thread types such as BSF, UNF, UNS, UNC, and others too numerous to mention (too complex to go into here but google is your friend)

 

 

Regards

[Spider]

I did have one once that couldn't be saved. I drilled & Tapped it 3/4" UNF. No issues from that.

[Bell-nose]

UPDATE

Thanks everyone I have a MUCH bigger problem now. One clutch puller has broken, bought a new one which arrived today evenly pulled the clutch which wouldnt come off even under extreme tension. I pulled one more time which resulting in one of the bolts that is screwed into the clutch being ripped from the clutch across the garage and now has ripped the thread.

As a result I cant pull the clutch anymore. Does anyone have any ideas im Not sure how im Actually going to get the clutch off to get at the gearbox.

Thanks.

[Northernpower]

Drill the flywheel and fit a helicoil. When you have the remover as tight as it will go hold a 1/2 drive socket extension at 90 degrees to the extended part of the flywheel (where it sits over the crankshaft taper) and hit the other end of the extension with a copper hammer. It will shock the joint between the flywheel and the crankshaft.

[Bell-nose]

Cheers, not worked. Im pretty sure this is welded on- never had problems like this before. If it is welded into the crank what are my options?

[Northernpower]

Cheers, not worked. Im pretty sure this is welded on- never had problems like this before. If it is welded into the crank what are my options?

http://www.guess-works.com/Shop/Parts/display.htm?id=501 

[cian]

The puller is not the issue ( well apart from the crappy Lazer ones ) you need to get the torque to where you cant physically turn the bolt any more then apply heat this always works for me with stubborn clutches

[Northernpower]

The puller is not the issue ( well apart from the crappy Lazer ones ) you need to get the torque to where you cant physically turn the bolt any more then apply heat this always works for me with stubborn clutches

I agree, I've never had a problem with a good puller and I've always found the shock method has worked for me without resorting to heat but I do understand the heat method. The key with the shock method it to hit it hard enough and I've never had one shatter the extension bar either,

[Bell-nose]

Okay thanks, out of all the clutches ive Pulled ive Never had the issues ive had with this.

Pretty sure Ive written the engine off now trying to get this off.

Is there any way to get a gearbox off an engine without removing the clutch?

[ukcooper]

seen hillclmime mins have em welded and then their scrap after .. I use the guessworks one its fab...

[cian]

Your not going to get the clutch off quick, next step is drilling and tapping or if you have a die grinder and a steady hand you might get lucky

[Bell-nose]

Thanks everyone.going to have to take it in.