undoing the infamous crank nut

Bailey

New Member
Hey guys, in the middle of a head swap on my 4g15 which is my first time pulling a motor to bits, only ever done a clutch swap and basic servicing/upgrades. im having immense trouble getting the crank nut (i think thats what id call it) off so i can get access to the crank gear. ive tried the starter method with a breaker bar but i dont think my starter is strong enough, it just clinked and did nothing. i have an air compressor and might have an old impact but not too sure on that. not sure how id stop the motor from rotating anyway. any advice?
 

donki

Administrator
Forum Administrator
Hey guys, in the middle of a head swap on my 4g15 which is my first time pulling a motor to bits, only ever done a clutch swap and basic servicing/upgrades. im having immense trouble getting the crank nut (i think thats what id call it) off so i can get access to the crank gear. ive tried the starter method with a breaker bar but i dont think my starter is strong enough, it just clinked and did nothing. i have an air compressor and might have an old impact but not too sure on that. not sure how id stop the motor from rotating anyway. any advice?
I believe the Gregorys manual describes the method as leaving the car in fourth gear, on the ground, and a big as *fudge* breaker bar. Dont ask me how to do that with the crank nut being on the bottom of the engine and the car on the ground but whatever haha. The other way is to bolt a steel plate to the flywheel (might need to remove the starter motor or inspection plate if there is one, and attach it to that spot, or jam in a screwdriver to the flywheel.
 

pelican

Active Member
I believe the Gregorys manual describes the method as leaving the car in fourth gear, on the ground, and a big as *fudge* breaker bar. Dont ask me how to do that with the crank nut being on the bottom of the engine and the car on the ground but whatever haha.
maybe if you can park it with one wheel up on a kerb or something, you can get a little extra space? you might only need to crack it a degree or two with the big *fudge*off breaker bar, just to loosen it enough to do the rest with a normal size breaker bar and a wrench :sweatsmile:
 

Bailey

New Member
maybe if you can park it with one wheel up on a kerb or something, you can get a little extra space? you might only need to crack it a degree or two with the big *fudge*off breaker bar, just to loosen it enough to do the rest with a normal size breaker bar and a wrench :sweatsmile:
intake manifold and exhaust manifold are out and coolant and oil is drained. up on jack stands with drivers side wheel off at the moment :///
stuff like this is starting to put me off cars haha
 

Bailey

New Member
also if i manage to get it off with the starter or something how in the hell am i gonna torque it back on? i have a torque wrench, but even so this sounds like a poo job
 

SDate42

Active Member
Lifetime Premium Member
My op is usually the starter motor and a breaker bar locked against a control arm. Maybe the battery is low, if the starter is only clicking?

Air impact gun should hit it easy, any compressor, a good hose (not sca/repco cheap junk) and even a basic $50 impact gun will knock it off.

the tightening torque isn’t huge when going back on, and if you used the gun coming off, itll cover you going back on
 

Bailey

New Member
the starter doesnt just click, it swings the breaker bar into the control arm like it should and clanks but never strong enough to undo the nut. also how do i reach torque specs if im tightening with an impact? that doesnt sound safe at all. i multimetred my battery and it was showing about 12.6v so id assume its fine. im honestly lost. i have a puller for harmonic balancers and such that would help heaps if the pulley actually had holes in it but its solid, so i dont know any other way to stop the damn motor from rotating
 

SDate42

Active Member
Lifetime Premium Member
Woah! Load the breaker bar against the control arm first, then crank the starter. It shouldnt be swinging around, that’s dangerous and won’t net the results youre after. Tie a cable tie around it if you need to secure it
 

Bailey

New Member
Woah! Load the breaker bar against the control arm first, then crank the starter. It shouldnt be swinging around, that’s dangerous and won’t net the results youre after. Tie a cable tie around it if you need to secure it
hah, i think i worded that a bit misleadingly, by swing i meant only half a cm to a cm of room between the bar and the control arm. i tried with it already resting on the arm but all i heard was a relay click when i turned the key
 

Bailey

New Member
Hey yall, my lancers still in the shed and half done and i thought id update to get some advice. i tried ziptying but once again my starter was too old and weak to break it. I then thought about what the service manual said so i took my bumper off, put the wheels back on and dropped it on the ground. I put it in 4th gear and tried the nut but my engine was still slightly rotating backwards. i dont even understand how this is possible to be honest, and the last thing i want to have to do is put it on a trailer and take it to a real mechanic
 

SDate42

Active Member
Lifetime Premium Member
Hey yall, my lancers still in the shed and half done and i thought id update to get some advice. i tried ziptying but once again my starter was too old and weak to break it. I then thought about what the service manual said so i took my bumper off, put the wheels back on and dropped it on the ground. I put it in 4th gear and tried the nut but my engine was still slightly rotating backwards. i dont even understand how this is possible to be honest, and the last thing i want to have to do is put it on a trailer and take it to a real mechanic
any chance of trying that air compressor you mentioned?
 

SDate42

Active Member
Lifetime Premium Member
impact wont fit with the wheels on and with the wheels off itll just rotate the motor
you can remove the sump, and stick a pry bar against the balance weight of the crankshaft and the crank case. Or go full rouge, rocker cover off and stick a spanner on the cam shaft and have someone else hold that for you. Be sure to have the spark plugs still in if youve taken them out.
 
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