View Full Version : How to: Crankshaft pulley removal
jesmine0
08-02-2009, 03:55 PM
Hi, currently I am facing a problems when removing the crankshaft pulley on my spare engine while the engine is out of the car.
When i try to unlock the nuts on the pulley, the crankshaft is actually moving and I cant do the job. So i 'jam' the power steering pulley and hopping that the belt will actually hold the belt system from moving. However, the crankshaft pulley slip on the belt and still turning.
So could anyone help me on how to remove them properly?
I had remove the crankshaft pulley that was currently on the car now by putting the wrench on the nut and support to the ground and crank the engine to create sufficient torque for removing the nuts. It is two second job. but for my spare engine that out of the car, I had no idea.
I know the other way you doing it is by supporting the flywheels from turning in order to remove the crankshaft pulley. But I dun wan to open the gearbox.
Anyone had other alternative?
The reason i wan to swap over the pulley is because the car got accident it bent the pulley. So i wan to swap the good pulley from my spare engine.
Thanks
Blulude98
08-02-2009, 04:04 PM
I know this might sound silly but i would take the engine to a tyre workshop/tyre fitter and get them to use there rattle gun , the reason why i am saying go to a tyre fitter is cause they loosen big truck bolts with there "double" impact rattle guns, i have done this before and it worked for me.
Mission
08-02-2009, 04:49 PM
There is a sst (special service tool) that must be used to hold the crank while you turn the nut. Honda service places have them. Ask to borrow one. Or you can make your own. Search on google and you will find how to.
jesmine0
08-02-2009, 11:28 PM
Thanks guys for the reply.
I had solve it :P
What i did is:
Pull out the starter - the reason is the starter is connected to flywheel and starting the motor by turning the flywheels.
So i pull out the starter, using .5" wrench and 'jam' the flywheels preventing it from moving, and unlock the crank pulley nuts. :P
The crank pulley nut is so tight like 245N.m.
I end up using 1m extension for the .5" wrench to untight it.
There is another way of doing it:
Put the wrench and 19mm socket on the crank pulley, support it on the ground.
hold the engine really firm and make sure it wouldn't fall when any side force apply onto it.
connect the negative of the starter to the battery,
touching the positive as quick as possible say 0.01 second to the battery.
this allow the starter to generate torque to the flywheel and turning the crank pulley.
since the wrench is supported to the ground, the crank pulley nut will get loosen.
But it is so dangerous that the engine will fall over. DO not under look the torque generated by starter. it can pull an elephant!! :P
jesmine0
08-02-2009, 11:36 PM
Also, just to point out that you never use impact wrench to unlock or lock the Crank pulley nut. This is because the crank pulley is fully balanced and using impact wrench will causing unbalance and destroy the crank shaft.
You never want an unbalance crankshaft.
ECU-MAN
09-02-2009, 07:56 AM
how does a rattle gun unbalance a harmonic balancer and crank shaft ?
can you shed some more light on this
dwn_boi
09-02-2009, 08:13 AM
I dont mean to spam, but if you had a prelude, they remove themselves :P
http://www.ozhonda.com/forum/showthread.php?t=81113
JasonGilholme
09-02-2009, 09:05 AM
how does a rattle gun unbalance a harmonic balancer and crank shaft ?
can you shed some more light on this
x2. Please explain OP.
jesmine0
09-02-2009, 11:52 PM
Yeah, check the honda service manual and helm manual. I try to attach the page but it fail.
I am not 100% sure why it does, but I do believe the impact wrench is generating unbalance torque to the crankshaft and it can permanent distort the surface into certain degree (hardly noticeable with eye).
Besides, the impact generated is so dangerous. you are not dealing with 10N.m or 20 N.m but 245N.m. The failure under impact is 2.5 - 3.5 times larger than the fatigue of metal (mechanical engineering).
ALso, when force are applied to the nuts, they are uniformly distributed throughout the nut and thread. Thus, nut will screwed uniformly and applying uniform force throughout the entire pulley.
But for impact torque, they are not uniformly loaded load and thus creating some "degree" of angle to the crankshaft. It might also causing damage of the lock pin on the pulley.
This is just my basic knowledge. not sure if it apply to the system. hopefully someone knowing better will let us know.
JasonGilholme
10-02-2009, 07:40 AM
when you're undoing the bolt you are not apply torque to the balancer. its going to the bolt which is threaded into the end of the crank which is being held in place at the other end (normally by a screw driver in the flywheel.
If anything you are applying 245nm of torque to the teeth on the flywheel. If you can do that without snapping teeth and destroying a screw driver then i'm sure the pulley will be safe.
I'm not sure on installation though. Maybe its recommended to be hand done. (if 245nm is even doable by hand haha.
Type S Tony
10-02-2009, 08:34 AM
Yeah, check the honda service manual and helm manual. I try to attach the page but it fail.
I am not 100% sure why it does, but I do believe the impact wrench is generating unbalance torque to the crankshaft and it can permanent distort the surface into certain degree (hardly noticeable with eye).
Besides, the impact generated is so dangerous. you are not dealing with 10N.m or 20 N.m but 245N.m. The failure under impact is 2.5 - 3.5 times larger than the fatigue of metal (mechanical engineering).
ALso, when force are applied to the nuts, they are uniformly distributed throughout the nut and thread. Thus, nut will screwed uniformly and applying uniform force throughout the entire pulley.
But for impact torque, they are not uniformly loaded load and thus creating some "degree" of angle to the crankshaft. It might also causing damage of the lock pin on the pulley.
This is just my basic knowledge. not sure if it apply to the system. hopefully someone knowing better will let us know.
When I was training at tafe as a mechanic this very question came up in class, THE RATTLE GUN DOES NOT EFFECT THE CRANK SHAFT IN ANY WAY, the crank has been designed to cop huge amounts of force through combustion & compression so believe me when i say an air powered rattle gun's vibrations is not going to effect the crank to any degree, if that was the case engines would be knocking and ceasing everyday everywhere, Oh and the fly wheel wasnt designed to have a screw driver jammed into it either, you can do some serious damage to the teeth if something stuffs up, especially on automatic vehicles.
jesmine0
10-02-2009, 12:13 PM
Oh and the fly wheel wasnt designed to have a screw driver jammed into it either, you can do some serious damage to the teeth if something stuffs up, especially on automatic vehicles.
Yeah, that true. wat i did is using .5" wrench extension to go through the hole on the flywheels (which perfectly fit) and stop the flywheel from moving.
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