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How to loosen crank bolt

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Hi Kurt,

They are amazing. I worked in an AMSA shop (Army Maintenance Support Activity) and we had a 3/4 and 1 inch sizes. Didn't take much pull on the handle but they were much more powerful than any impact.

I would think the smallest size set would be at least $1200 so it is a little much for a home shop. That is why I suggested renting one. But it might be worth checking with a Reserve Unit if they have any heavy equipment in their motor pool.
 
The starter turns the motor over, but with the breaker bar wedged against the inner fender, the starter does not have enough power to break the bolt loose.
 
:iagree: Right. Lucas starters were purpose designed that way so as to not bend the body work or break your tool.
 
This method is a last resort! And ... the bolt will be non serviceable after you get it out! Use a drift, preferably the same diameter as the bolt head and a large hammer. Hit the bolt squarely on the head as if trying to drive a nail, hit it as hard as you can, Try not to disfigure the bolt head to the point you can not get a socket on it. Try turning the bolt with your breaker bar, if it still won`t budge .... try the procedure again.
This is a trick taught me by an old junkyard dog to get flywheel bolts out .... trust me .... it works!
 
If you don`t like the idea of hitting the bolt for any reason, you could try a torque multiplier but you still have to figure out how to keep the engine from turning. The multiplier I have is 1:64 but quite a large tool not well designed for tight quarters. here is one that may work , it is only 3:1 but it may be enough
https://www.northerntool.com/shop/tools/product_200315001_200315001
 
Hi Kerry,

I like your idea of hitting the bolt. Would work similar to the smaller hand held impacts for getting screws loose in aluminum castings (motorcycles).

I was also wondering if he might use a large strap wrench on the pulley and a breaker bar on the bolt. I have a strap wrench like that with a 12" handle. Wondering if a cheater pipe on the bar might then help or maybe hitting the bar or socket while pulling on the bar.

I should have thought of this sooner, and a photo.
 
So have we eliminated all possibilities of Rightey Tightey / Lefty Loosey. Are you certain you are trying to loosen the correct way? Just one more time to make sure before you break something or hurt yourself.
 
tomshobby said:
Hi Kerry,

I like your idea of hitting the bolt. Would work similar to the smaller hand held impacts for getting screws loose in aluminum castings (motorcycles).

I was also wondering if he might use a large strap wrench on the pulley and a breaker bar on the bolt. I have a strap wrench like that with a 12" handle. Wondering if a cheater pipe on the bar might then help or maybe hitting the bar or socket while pulling on the bar.

I should have thought of this sooner, and a photo.
Click to expand...

If this car is std transmission I would think putting the trans in reverse and setting the e-brake should suffice in keeping the engine from turning IF he can hit that bolt hard enough and squarely it WILL come out rather easily. in fact I have removed flywheel bolts with an end wrench because I buggered up one shoulder of the bolt while striking it to the point a socket would no longer fit.
 
Gee fellas- just take out the engine or raise it enough to get a proper air/electric impact on it, job done!

tho i do like the strap wrench idea...need to be a really large one.

I can vouch for hitting it on the head with the bfh a couple of times, that works. but to hit it well you will probaly need the engine raised or out of the car.


m
 
Using the E brake bends axles on Spridgets. ( ask me how I know).

You can just wack the head of the bolt with a hammer too instead of using a punch.


I'm with Dad ( as well I should be). I'd drop the pan and put a 2X4 b/w the crank and block. I'm not too hip on the rope trip for this.
 
If the starter won't do it, and you don't want to yank the starter to jam the ring gear, drop the pan (it needs a new gasket anyway, right?) and pipe or 2X4 blocking the crank to the block.
I have an 18" breaker bar and a 40" piece of pipe for a cheater.
If you pull the pipe towards you, don't pull it towards your forehead, please.

The worst to get loose was Hondas. Seems there was something in the thread pitch on the crank and end bolt, and geez, we had to try a lot of things to get that off, but we always did.
I cannot imagine this being even that tight.
I mean, we're dealing with Brit tolerances, fercrissakes.
You're in California, and unless the engine came out of a Massachusetts rustbucket, it HAS to come off.
 
You really are loosening it right??
As you stand at the front of the car looking at the front of the engine the cheater pipe on the breaker bar should move to the left to loosen.

If you hold your two hands out and make an "L" with your thumb and finger the one that makes a backwards "L" is your RIGHT hand.
The other hand is your LEFT hand...

Just checking... don't shoot me!

:jester:
 
Take a look at the tool used to block the fly wheel on a vw bug. It will slip into the hole where you stater goes and locks into the fly wheel teeth. The is a nut in the center to lock it in place against the tranny housing. The use a breaker bar on the nut. I used this on my midget and my Spitfire.
 
Grrr....darn Car. Why is somehting that is in theory so simple becoming so painful. And yes, I am turning it the correct way :p
I'm going to go top off the battery and give the starter thing one more try after I beat the bolt with a hammer and a punch. I really with I had pneumatic tools about now. Hmm....reason #1 to go buy a compressor.....
 
Miss Agathas had to come out with heat, lots of heat. But then the crank was broken in half if you remember.
 
bugedd said:
I really with I had pneumatic tools about now. Hmm....reason #1 to go buy a compressor.....
Click to expand...
When I was trying to disassemble my 1275 (out of the car) I fought with that bolt for a week or two using everything I could think of. Then I went and bought a compressor and impact wrench and had the bolt off in about 10 seconds. I use the compressor all the time now. Well worth the investment.
 
And a big enough compressor to do the job.An investment in one that moves a serious amount of CFM is required.
 
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