Removing stripped flywheel bolt

[Paul Garvey]

'Fun-times'...serves me right for taking on an 'un-finished project'...  

I've just replaced the stripped front oil sealing block with a cnc steel one and now onto the clutch and found a stripped flywheel bolt so thought best to fix and check the torque settings. I don't know what grade or how much loc-tight used or torque settings but it hasn't been fun - in fact it's been worse than replacing the oil sealing block from under the car.  I managed to remove three of the flywheel bolts with a long breaker bar - but the last one...I tried heat, direct hit with hammer and breaker bar - no luck so ground off the top off the bolt, took off the flywheel and....heat, hammer and big vice grips - still no luck.  I could try an easy out but I'm not convinced it'd work as it's so tight and the only option seems to be to drill it out - no something I'm keen on doing.

Anyone got any suggestions?

Paul

[Paul Garvey]

Sorry 'rounded' bolt.

[nang]

Paul, can you get at it with a mig? May be able to tack something on it and the heat may help also.
Tony.

[piman]

Hello Paul,

a Stillson wrench will grip better than a pair of vice grips, with a bit of tube for extra leverage, however it sounds like the threads have galled so may well be damaged. I would give up trying to remove it if Stillsons don't work. You have already tried heat so I don't think further heating will help.
To drill it out, I would replace the flywheel (After carefully cutting the damaged bolt flush with the crank flange) and have made or find a sleeve that will fit snugly into the flywheel bolt hole with a bore to suit whatever drill you are going to use. This will centralise the drill and help to keep it perpendicular. You will probably have to drill to tapping size then retap the hole. It is possible that the threads will be damaged in the crank and you'll end up having to fit a helicoil?

Alec

[TedTaylor]

If it is a rounded head you could try one of the special removers for this purpose.  I have a set and have found them very useful in emergencies for rusted in/painted over bolt/nut heads - that someone else has knackered of course  ::)

Irwin http://www.irwin.com/tools/browse/screw-bolt-extractors/bolt-extractors are the original ones and arguably the best but Laser tools also do sets.  Because of their design a metric size also works with imperial.

Have a look on ebay - less than £20 for a set.

[Richard B]

Use a Mig to weld a nut onto the remains of the bolt.

This has two advantages;

• It applies a lot of heat into the bolt (gets it redhot)
• It geves good purchase with a socket set to turn it.

If the weld breaks, weld it on again.  (You do want a good welder, something that will well 3 - 6 mm plate).


This has worked a number of times for me with 6 pot cylinder head studs.

Alternatively you can have it electrospark eroded. Over here that costs about £40.

[Paul Garvey]

Thanks all,

I'll borrow a set of Stilsons and have a go on the weekend then if that doesn't work have a go with the mig and weld on a nut.  

If that doesn't work I can hire an oxy-acetylene setup and put in some 'extreme' heat, however wouldn't this damage the rear seal???

I haven't heard of electrospark so will have a look locally and see if there's anyone who could  come out

[Paul Garvey]

Mmm...I rang a local specialist Triumph mechanic and my local mechanic.  They both advised not to use excessive heat as will damage the rear seal.  They both suggested a few days with WD40 then spray onto the bolt a Wurth product called Rost Off Ice - essentially it's dry ice with a pentrating compound.  Certainly a different approach so will see if the local Wurth distributor has any.   They both also liked 'cam-lock' stud removers but doubted I'd have enough length to use one effectively.

[piman]

Hello Paul,

as the flywheel is off, just remove the seal?

WD40 is not a good penetrant but I feel it's not tight due to rust etc like fasteners under the car so I'm not convinced more heat will help. (Or cold for that matter)

Good luck.

[Sheepy]

Wd40 is not a penetrating fluid as pitman said, plus gas is the best one I know of!

But also as piman said, don't think that will help, as it could be the threads have gripped it tight, perhaps the previous person who fitted it cross threaded it!

Good luck

[GT6]

Maybe of interest is a post I've lifted from elsewhere:

Machinist's Workshop magazine actually tested penetrants for
break out torque on rusted nuts.

Significant results! They are below,They arranged a subjective test of all the popular penetrants with
the control being the torque required to remove the nut from a
"scientifically rusted" environment.

Penetrating oil ..... Average load
None ...................... 516 pounds
WD-40 .................... 238 pounds
PB Blaster .............. 214 pounds
Liquid Wrench ........ 127 pounds
Kano Kroil ............... 106 pounds
ATF-Acetone mix.......53 pounds

The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
transmission fluid and acetone.
Note the "home brew" was better than any commercial product in
this one particular test.

Note also that "Liquid Wrench" is about as good as "Kroil" for
about 20% of the price.

[TedTaylor]

Were the original bolts fitted using thread locking compound (e.g. Loctite) because I would be surprised if they would be rusty in that environment (but could be wrong ........ :X)

If you have removed some bolts has the thread a deposit (usually white and by now slightly powdery) in the thread itself.  If so then it is most likely thread locking compound has been used and therein may be the problem ...... wrong type (stud lock?) or some one too enthusiastic in the application (only a drop should be used).

If the bolt is jammed up because of thread locking compound then to release it you may need to get it very hot to break down its chemical structure and that can usually only be done with oxy-acetylene.

GT6 very interesting your info on penetrating lubricants.  Looks like I will be getting some acetone or experimenting with other organic solvents such as celly paint thinners that ATF is miscible with!

[Paul Garvey]

Yes, way too much Loctite used and far too much torque.  I'll have a go in the weekend and post the results...thank you all much appreciated.

[Paul Garvey]

Heat, heat and more heat - no, Rost Off Ice - no, Stilsons - no.  I'd try the ATF-acetone mix if the - no-gearbox - engine angle didn't mean it would just ide off with gravity rather than sit and penetrate.

I think the previous owner must have cross-threaded and made up for it with a bucket load of Red Loctite so thinking it'll be an engine out jobbie/strip and unfortunately I don't have the enthusiasm for that much of a step backwards again - restored x3 cars before this and this one has been the restoration from hell - definitely put me off ever doing another.  Fortunately I've a triple garage and only the Spitty in it so think I'll just walk away for a few months and then decide what to do - mind you I can't wait too long as is Red Stickered for demolition post Earthquake so has to come down with short notice - which is why no other cars in it.

[junkuser]

Drilling a hole in a bit of suitable flat bar, placing it over the bolt and welding it on, worth a try first isn't it?

Suppose it depends on how much bolt is remaining at this stage.

Seems difficult to cross thread a bolt that is passed through a flywheel but using a bolt with incorrect thread pitch or length may have been done by someone.
'Tis amazing what one can find in old cars.

[nang]

I tend to agree with junkuser. However if this fails I'd drill it out. First grind it off flush with the flywheel. Start with a small drill and go up in increments until you reach tapping size. With a bit of care and starting with a taper tap I think you would be able to get it square.
Tony.

[Paul Garvey]

Done it....1.5 hours, borrowed digital heat gun - whacked up to 500 degrees - that and vice grips 1/8", repeat to keep heat up, repeat....worst job ever done on a car - hands will be aching tomorrow but now it's Beer o'clock...

Thanks people for your help - BEWARE Red Loctite and his evil twin Overtorque!

[junkuser]

Good on you Paul. Just shows all problems are solvable.

Enjoy your beer.  (Might just have one with you)

[rotoflex]

Congratulations on your success!

I wonder if the loctited bolt would have been as immovable if an impact gun was used to turn it.
I know everyone doesn't have one available, but I bought an electric one fairly inexpensively which as been very good for removing many stuck fasteners.

[CHRIS211083]

Usually I would say hit the gym Paul!!!

However Red locktite is tuff stuff. Well done that man. A friend of mine uses it to stop bearing shells rotating and its seriously tough stuff. Even with heat.

So Well Done That Man!!!!

Chris.

[GT6]

Good news Paul, edging closer with every job. I can see a dim light at the end of the tunnel on my spitty,
on closer inspection it is nearer than i thought, turns out to be a lucas 7" sealed lamp on hi beam.

[TedTaylor]

Red loctite ..... sounds like StudLoc.  

NOT the right stuff on a nut or bolt because it is meant to be used on something that is not meant to come undone ........ as you have found  ??) !!!!

Ted