Jump to content

Crankshaft confusion


SolihullBeast

Recommended Posts

I am in the process of attempting to remove the timing cover from 200tdi disco, in order to repair suspected broken timing belt, the only remaining thing obstructing its removal is the crankshaft pulley, I am aware the large bolt can be done up very tightly and there are several ways of getting it to undo,

1. use a special/homemade tool to hold the pulley steady whilst the bolt is undone

2. Put the vehicle in difflock low ratio and the main gearbox in 1st and turn the nut against the resistance now created

3. wedge a breaker bar under the front chassis rail and turn the engine over(last resort)

In the absence of a special tool to hold the pulley steady, and my reluctance to try the last method(also as the battery is flat!) I have attempted to undo the bolt using the second method, however it has not gone to plan; With the vehicle in the gear setup mentioned above, and pushed until gears give resistance I had a helper depress the brakes and I attempted to undo the bolt however the crankshaft kept turning over as I attempted to undo the bolt as if it was not in gear, so i checked again and pushed the car whilst it was in gear to be absolutely sure it was in gear and it was, the wheels came to a stop when it was pushed. So given the fact it was in gear and the crankshaft bolt would just turn over when I tried to undo it, I came to following conclusion that either the clutch was slipping or the crankshaft itself was broken. Considering the clutch is two months old I assume it is unlikely to slip? and the pushrods move correctly when the engine is turned over manually suggesting the crankshaft is not broken?

I am by no means a mechanic, I am a novice lr enthusiast- so if anything I have said here does not make sense, or is incorrect I apologise!

Can anyone shed any light on why the crankshaft turns over so easily manually when i try to undo the bolt when in gear? Have I missed something?

Many Thanks

Sam

Link to comment
Share on other sites

You haven't missed anything. It'll be the clutch slipping!! Doesn't matter how fresh it is...

Try method 3. In my experience it's taken a flick of the key to crack the nut. You don't even get the engine fired up. 10 minutes with the battery charger should see it with enough juice to perform the required task.

Link to comment
Share on other sites

If the pushrobs are all pushrodding when you turn the engine over, then the cambelt cant be broken :unsure:

With the vehicle in gear you will have to put a few turns on the crank to wind the transmission up tight. Only then will you start to feel the resistance.

Good luck!

Dan

Link to comment
Share on other sites

Take the wire off the injector pump so that the engine won't start, then use the starter motor method. I do this 100% of the time and it pretty-much always works first time. You'll be there forever if you try the transmission wind-up method. If the rockers are moving, then the belt hasn't snapped, but may have jumped a couple of teeth - preventing the engine from running. Stripped timing belt teeth is rare on non-Freelanders, but does happen sometimes.

Les.

Link to comment
Share on other sites

i second that ^^

With first low, your gearbox/txb/diffs are multiplying the force your applying by something like 30times before its applied to the wheels, and will have to turn quite a fwe times to take up all the slack in the various transmission components.

Use 5th high.

Link to comment
Share on other sites

Answers to the various questions;

1. Yes the helper was definitely pushing the brakes, he knows his pedals! cheers for the input though, you never know!

2. when i say the pushrods are functioning I mean they are moving slightly when it is turned

3. Sorry for my ignorance but I don't know what a Windy Gun is!!?

4. The symptoms that made me suspect that the cambelt had gone were, bent pushrods, fractured and broken rockers and timing belt dust under the airconbelt tensioner cover, but as you say, I am quite possibly wrong

Its looking like i am going to have to bite the bullet and try the starter motor method!

Much appreciate the input, thanks to all

Link to comment
Share on other sites

this is an impact gun, windy gun, rattle gun, impact wrench etc :)

but you'll need a decent compressor and decent gun to undo it.

you can get 12v or 18v versions, but not sure how strong - depends on the make ;)

154156_lg.jpg

G

Link to comment
Share on other sites

Cheers for the explanation regarding the windy gun, I have learnt something new today! fortunately today has proved a successful day, I did not have to use the starter method! Thanks to all those who suggested putting it in 5th high ratio, the bolt cam off like a charm, cheers for the advice, much appreciated! Now I am faced with the problem of removing the metal disc(not sure what its called) that sits behind the pulley, any ideas?

Sam

Link to comment
Share on other sites

Metal disc - you mean the crankshaft damper (big lump of metal with a rubber strip around the centre face). This should come off once the bolt is removed, but quite often is stuck - sometimes really badly. You can apply some leverage behind it, but be careful not to damage the timing cover. Alternatively - you can make up a fairly simple puller from some thick metal and a couple of bolts.

gallery_2_301_293447.jpg

Les.

Link to comment
Share on other sites

Now I am faced with the problem of removing the metal disc(not sure what its called) that sits behind the pulley, any ideas?

Sam

it's called a harmonic damper, you could make up a puller as shown in this thread http://forums.lr4x4.com/index.php?showtopic=14285

or try with prybars/tyre lever & prise it along the crank nose.

Link to comment
Share on other sites

had a go with prybars and it did not budge, and I'm cautious of being heavy handed and cracking the timing cover, looks like im going to have to buy a special pulling tool! I can't make one as I am up at uni with a basic tool kit!

Sam

I have never liked the starter motor method as the bar usually comes flying off and there is too much for it to damage. What I have always done is remove the cover at the front of the transmission under the motor. I have some little bits of metal that neatly fit between the bell housing while lodged in the teeth of the flywheel. But a screw driver will work just as well, especially if you have someone to hold it. You lodge it in the flywheel just as it disappears behind the motor. this way the back of the motor acts as a stop to prevent the flywheel turning. Put on the left side of the flywheel to undo the crank bolt and on the other side when you tighten it back up. You still need a bloody big breaker bar to undo the thing.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy