Crank bolt

[trentlane87]

How do I tighten the crank bolt on a daewoo lanos 1.5L without turning the engine, i stuck a screwdriver in between the cam gear snd broke the cam box! now replaced that and the head gasket and at the same point again, a spamner wont fit im between the gaps to hold the camshaft dieectly, and the flyywheel teeth seem small to hd with a pry bar, thinking of just rattling it up with my impact gun, any help?

[NubiraTurbo]

Never turn the engine against the cam!!!!!! Also no rattling gun!!!! Spray crank bolt with Q20 or some very thin oil. Go underneath the car. There is a cover under flywheel with, i think 4 small bolts or something. Not the gearbox sump! No oil should come out when you loosen the bolts. You'll see the ring-gear. Hmm, maybe that's the "flywheel teeth" that you've mentioned. Wedge a big flat screw driver in between a tooth and the casing. Slowly turn engine till screw driver is locked in there nice and tight, checking if it's not pressing against a sharp corner of a tooth or something that can be damaged. The screw driver must not "want to jump out" when you turn the engine against it. Also check that it is wedged in the right direction for you to undo the bolt, and again when you redo the bolt. You should be able to see if there's a chance for damage. If the bolt is really tight; put a little tension on it with spanner (the tension is just to keep the spanner nicely in place) and tap the spanner with a hammer. Not too hard. Don't use hammer when you redo the bolt. Done this twice on mine (1.5 Lanos). Worked like a dream.

[trentlane87]

Hey, thanks for the reply, are you talking about on an automatic transmission? mines a manual and I can't seem to find the 4 bolts and plate your talking about, I've removed the starter motor, hoping to hold a pry bar or screwdriver in there whilst i tighten it, otherwise there are hexagon shapes machined into the camshafts I just can't fit a spanner head in there to hold it, so was going to get one machined down. Rattle gun was going to be my last resort, it's hard when you have no one there to help.

[Daniel]

Hi,

The purpose for hexagon shapes machined into the camshafts is for fitting/removing camgear(s) bolt(s).
Certainly not to keep crankshaft from turning while you fit/remove crankshaft bolt. This way you'll put alot of stress on the cambelt which is not made for this.
Personally I've removed the crankshaft bolt by the "starter method" and torque it again in 4th gear while a helper hold down brake pedal (doable only if you have studs on rotor).

[NubiraTurbo]

It's a pleasure. Yes mine is also manual. I'm not sure if it is 4 bolts, might be more; 10mm I think. The starter motor runs on that ring gear that i've mentioned. The plate is about 20cm long and 15cm wide if i remember correctly. Just follow that big gear on the flywheel (on which the starter motor runs) and you'll find it. Not the one directly under the gearbox, that's the gearbox's sump. If there's oil coming out, your on the wrong path.

Also, Daniel's got a good point about torquing it while in 4th, with someone on the brake.
Daniel, wouldn't that also work for removal? I'm sure it should, just not sure about the strain/torque on the gearbox.

[Daniel]

Hi NubiraTurbo,

To tighten the bolt this method works. Do not be afraid for the gearbox. It takes a lot more stress in normal daily driving.
Be warned not to use this method if your disk brake is fixed only by the detent screw.

I tried this method to loosen the crankshaft bolt but did not work. The reason is that to unscrew that bolt the needed torque is approx two or three times stronger than the inital torque. And transmission elasticity didn't allowed to have sufficient angular clearance for that. Hence I used the "starter method". Quite crude but efficient.

[trentlane87]

Thanks heaps for the advice everyone I think I'm going to try the '4th gear' method, just a couple of questions, is 4th gear the best gear to do it in? and also, my rotors don't have studs, should I put the bolts in the rotors to hold it or something?

Another question, how do you tighten the camshaft bolt? the hexagon shape in the camshaft would be ideal but I can't fit a spanner in there the head of the spanner is too big, if there's another way for that to be done i would appreciate the advice, I'm too scared to jam a screwdriver in between the cam gear again in case I snap the cam box again.

Sorry for all the questions.

[Daniel]

I found the 4th gear to be the best compromise for me between what brakes can hold and transmission elasticity. And yes, put bolts in rotors or the detent screw may snap.
Edit: just remember another way to keep crankshaft from turning: http://www.daewootech.com/forum/viewtop ... el#p112667 .

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You may grind the spanner to fit.

Edit: Reminder Don't use the brake method to hold camshaft in place