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Remove Crank Nut

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B

BG 62AH

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Help. I need to replace the timing chain cover/crank shaft seal. I have not been able to undo the nut that holds the harmonic balancer on.

The tab is bent back, and I have sprayed everything with PB Blaster.

I have not been able to keep the crank shaft from rotating. It looks like there is a fitting on the very front of the end of the crank shaft.

My car is a BJ7.

Any advice on this (and getting crank pulley and timing chain cover off) the shaft is really appreciated.


Thank you, Bill
 
Put the car in first gear, set the hand brake, chock the wheels and then turn the nut. There is no fitting on the end of the crank shaft.
 
Get an impact wrench and it wil spin off for you.
 
Keoke said:
Get an impact wrench and it wil spin off for you.
Click to expand...

x2. That is the easy way. Start with lower torque on the impact, in case it is really tight on there. Although the crank is beefy, some of the big impact tools (3/4" or 1" drive) could snap something if the nut did not come off easily.
 
Put big box end wrench on nut. Rotate pulley CW until wrench hits frame. Stand back and give the starter a short burst (pull coil wire first). Nut will be loose now. Just make sure the wrench fits firmly and rests against a solid part of the frame.

It's risky but it has worked for me with several cars....

Good luck!
 
Healey 100 said:
Put big box end wrench on nut. Rotate pulley CW until wrench hits frame. Stand back and give the starter a short burst (pull coil wire first). Nut will be loose now. Just make sure the wrench fits firmly and rests against a solid part of the frame.

It's risky but it has worked for me with several cars....

Good luck!
Click to expand...

Make sure you undo the locktab first.
The 1-11/16" combination wrench is available on Amazon for $20.50.
screenshot.83.jpg
 
Hi Bill,

I totally agree with the use of an impact wrench and, if torque adjustable, use a medium torque setting and don't be surprised that it takes a you multiple efforts or an extended period before the nut brakes loose. If you do not have an impact wrench, look to rent one from one of the local parts houses. Along with the your seals and chain, make sure you consider changing the timing chain tensioner.


Good luck,
Ray(64BJ8P1)
 
Guys, thank you all for your advice on this, I really appreciate it. One of these will work.

Ray, (fellow PEDC'er and mentor) thanks for the reminder on the chain and tensioner! good point.
 
After trying everything else--including the starter 'trick'--I broke down and bought a 3/4" impact wrench from Horrible Fright. The problem is the length of the wrench won't let it fit between the nut and the front cross-member; had to undo the nut with the wrench canted at an angle and buggered-up the nut. They're available, but not cheap and they don't have the inner bevel to clear the threaded part of the crank but seem to work.
 
bdcvg said:
Did You loosen motor mounts and lift the engine up a smidge first?
Click to expand...

YES Jack the front of the engine up just a bit:encouragement:

Place a piece of 2X6 under the pan and then set the jack and raise it up.
 
I had the same problem on my 100, I was working with a breaker bar with a cheater pipe attached for even more leverage, I ended up bending the professional grade bar (SK tools if I recall right) and then snapping off the half inch drive on it. An impact wrench got me nowhere. I eventually bought a big old combination wrench, and a few hits with a wire wheel hammer and it came off. The breaker bar actually had quite a bit of flex when you really pushed it, the combination wrench, with the broader cross section did not, I think some of the old manual even refer to such items as a striking wrench or something like that to be used in just such situations. Worst stuck nut story I have, struggled with it for days off and on.
 
Thank you all for the suggestions. I really appreciate all the feedback, it seems every Healey owner I talk to about "the nut" has had some real fun getting it off.

I have ordered a 1-11/16" combination wrench, which I plan to use as a striking wrench and/or use the starter trick with. The wrench is not here yet. At this point I am not planning on raising the engine because I plan to build a small fixture to lock the harmonic balancer in place (as some members have suggested). Should be able to get the wrench on the nut easily enough.

Plan B is the impact wrench, in which case I guess I will have to raise the engine and make a new fixture set up.

Has anyone heated the nut with a torch, I have been wrestling with this idea, but did not was to warp or damage the crank?

Releasing fluid doesn't seem to be doing much, although I have continued to spray it.

Thank you all so much.
 
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