Crank pulley nut: huge breaker bar or impact driver/wrench?

[PhilBell]

Can anyone confirm which will pose the lowest risk of damage to the engine and transmission please?

With the car in top gear and with an assistant applying the footbrake, the nut won't budge with my 24in breaker bar. And yes, I did have three Shredded Wheat for breakfast beforehand.

Options include investing in a 39in breaker bar from Draper, a Laser impact breaker bar or an impact wrench.

[mgcjag]

Have you removed all the lock tabs.........i find a cheep usefull extension tool is a lenght of old steel waterpipe or scaffold tube.. Steve

[kingzetts]

Phil,

Not sure how you get access with an impact wrench unless the radiator and picture frame are already removed (at least on a 6 cylinder - not sure about V12).

The technique I used was to get a long metal bar or square box section tube, drill it to fit 2 adjacent of the 4 bolt holes in the crank damper for the crank pulley and bolt it in place so it braced against the garage floor or similar. Then I used a very long breaker bar on the damper nut (from memory a 3 foot one), and I may have added a piece of tube as an extension on the breaker as Steve suggests.

Good luck!

[ALAN COCHRANE]

I did this recently in the car with it just in top gear and hand brake on but was probably just lucky.
I used a two foot breaker bar and gave the handle a sharp whack with a 2lb hammer. The sudden jolt was enought o loosen it.
If youo're taking out and splitting the engine and gearbox you can jam the flywheel against the block with an old cylinder head stud or the like. In my case this was enough to loosen all the set screws holding it on and would probably do the same for the crankshaft damper bolt.

Cheers

Alan

[johnetype]

The answer depends on where the reaction to the torque you're applying is going to go.

If you are holding the crank stationary through the crank, clutch, gearbox, final drive and finally into the rear brakes then if you use an impact wrench or airgun all of those elements along the way will absorb the impact which is potentially not good for them and means less direct effect on the bolt you're trying to undo.

If you do what John suggests and restrain the damper pulley by a bar resting on the floor then only the bolt and pulley are being acted on so there's no chance of damage to the crank or any other damage and any impact device will be concentrated on the bolt.

Personally, if the bolt won't budge with a 3 foot breaker bar and you're holding the crank stationary with the brakes I'd consider that the limit although I would prefer to use the flywheel ring gear as the place to lock the engine at and eliminate the clutch etc. If that won't work, I'd move to John's method of holding the pulley firm against say the floor and it's game on for the longest breaker bar or impact device you can find until the bolt lets go.

[abowie]

Use a hammer on your breaker bar or a ring spanner. You can't get an impact driver in there.

I use a foot long piece of flat 3" x 1/4" bar that I have welded a cut down socket on the end of.

[keithmac]

I feel your pain. It took me a week to get mine off. I tried everything.As previously mentioned , what finally worked for me was removing the started and blocking the flywheel against the bell housing and of course , a breaker bar with an extension. It came off on the second try with a crack like a gun going off. I thought I had broken it off !
I used a small piece of oak I shaped to fit the teeth of the fly wheel with a long safety wire attached in case it fell into the clutch housing.
You will prevail !

[PhilBell]

As a veteran of three IRS removals/rebuilds I was starting to feel invincible. This has retaught me humility.

[ands59]

Don’t give up it will move eventually
I nearly gave up but it did shift after WD40
Did this last summer with
1 Engine in top gear
2 Wheels chocked
3 2 foot breaker bar
4 lump hammer
5 WD40 3 times in 24 hours
6 Good strike hammer to breaker bar
Very loud crack and then hand released nut
Best of luck
Andrew

[Hugo]

Easiest job in the world. Put a wrench on the nut & hit the starter. It'll come straight off.
You might want to tie the wrench to the frame somewhere & put a piece of wood in an appropriate place so you don't damage anything.
I'm in Florida right now playing with various cars. I decided to change the harmonic balancer on my Impala, and was staggered to find there is nothing holding it on but will power. It is pressed onto a keyway & that's it. No bolt, nothing.
My Corvette engine is the same. The Impala has a 348 & the Corvette has a 283, from 1960 and 1961 respectively. Later ones had bolts, apparently. The early ones, I am told, don't come off very often, which is kind of reassuring.

[PhilBell]

Cracked it!
Bolted a couple of lengths of Dexion, (doubled up for strength) across the pulley bolts and braced it against the garage floor. Lengthened the 24in breaker bar with a trolley jack handle and gave it a good heave. Released quite gently in the end.
Pulley came off easily with a 3-leg puller. Damper is currently putting up a fight.
Thanks for all of the advice and encouragement chaps.

[david muir]

flogging spanner and hammer!

[rfs1957]

If you are holding the crank stationary through the crank, clutch, gearbox, final drive and finally into the rear brakes then if you use an impact wrench or airgun all of those elements along the way will absorb the impact which is potentially not good for them and means less direct effect on the bolt you're trying to undo.

Couldn't agree more ; it's the acceleration you impart on the bolt, catching it by surprise, that determines how much useful effort you're actually applying to undo it. Just like banging against a decent anvil.

Otherwise, all the slop from bolt-head through to rear brakes is soaking up the jerk.

The best mechanical advantage - through the bigger radius - you can get is to wedge the flywheel through the starter motor hole, but be beware that this can damage the teeth if you're not savvy about how the wedge is angled and shaped.

I've always been surprised that no tool is commercially available to do this - with my motor out right now, I'm going to make a sort of dummy pinion, but straight not round so that it will share the load over several teeth, that fits into the starter hole.

[Hugo]

A lot of discussion on how to make an easy job difficult . Just stick a wrench on the nut, hit the starter and you're done ;)

[sjclark]

Just removed the crank bolt today, after trying most of yesterday. Long breaker bar plus tube to add more leverage and judicious use of a lump hammer to put some shock loading into the joint, with the pulley anchored with a piece of angle iron drilled to take two of the four pulley bolts, and in contact with the floor. Plenty of penetrating oil several times yesterday and this morning. Today, after more penetrating oil, and re-positioning of the angle iron onto the other pulley bolts, it finally succumbed to more torque and hammering.

Next step was to tackle the torsional damper, which I had not been looking forward to, given the tightness of the bolt and some other write-ups on this forum. With a good flat plate puller, however, that part of the exercise was almost an anticlimax when it parted from the cone with a gentle pop.

Now to remove the engine...

[Hugo]

Just removed the crank bolt today, after trying most of yesterday. Long breaker bar plus tube to add more leverage and judicious use of a lump hammer to put some shock loading into the joint, with the pulley anchored with a piece of angle iron drilled to take two of the four pulley bolts, and in contact with the floor. Plenty of penetrating oil several times yesterday and this morning. Today, after more penetrating oil, and re-positioning of the angle iron onto the other pulley bolts, it finally succumbed to more torque and hammering.

I reckon my method is easier - takes 30 seconds ;)