Daewoo Nexia Head Gasket - horatio
I will use this thread for any questions I have on this job

Daewoo Nexia 1.5L 8V SOHC 1997 P reg, Engine is basically a vauxhall SOHC

I have so far removed the air box, wiring loom from top of engine, alternator & belt, Air con belt, exhaust manifold heatshield, fuel feed pipe and return from the fuel rail. Top half timing belt cover, and eventually got the lower half TB cover off aswell.

I have lined up the timing marks top and bottom, top slightly out when bottom lined up, so I marked where the top was (with bottom lined up). Is this correct?

If you have access to data sheets I'd appreciate some help, or just from your experience.

The bottom timing pointer, is on the lower half front timing belt cover (i.e. the bit that you remove) so I am concerned about that because with the cover removed, I have no reference point to make sure everything is still ok, or to reset it if I move the lower sprocket.

There were 3 retaining screws for the lower TB cover, the 3rd in the middle was behind the crank pulley??? I used an offset 10mm ring spanner to get it off but my spanner did not seat very well, and I'm not sure about how good it will be in tightening on refitting.........So, Are you supposed to remove the crank pulley? before removing the lower TB cover? - note this pulley only has one single bolt - presumably goes through the crank sprocket aswell!

If you are supposed to remove the crank pulley.......How to do this? Do I put it in 2nd gear?
And then if the crankshaft moves I just line it up again before I remove it completely. How about refitting the crankshaft pulley? Is 2nd gear going to be strong enough when I put about 100 lb/ft on it? - Can you give me the precise torque settings (listed below). The crank pulley only has one central bolthead 18mm hexhead, holding it on, presumably this bolt goes all the way through the crankshaft sprocket aswell? My vauxhall book, shows an engine which has 4 outer bolts (20Nm) which hold the pulley to the crankshaft sprocket, this Daewoo engine is not as easy as that.

Once I have removed the crankpulley and the TB cover. I can see there is a waterpump sprocket, I can see one allen head retaining screw for the waterpump, But I cannot see the other two screws - presumably when I have the crankshaft pulley off, I will see the other two waterpump retaining screws? Next to the waterpump sproket there is a spindle where the belt goes round on the flat side of the belt. It is a similar diameter spindle to the size of the waterpump sprocket. This spindle appears to be retained with a 13mm hex head bolt, this bolthead was visible through a hole in the lower TB cover - which did lead me to think that it might be linked to the method of tensioning the TB (without having to remove the TB cover. But I think now, it has nothing to do with tensioning, and is just a spindle - Am I right about that?

I need the torque settings for:
Crankshaft pulley/sprocket bolt
Camshaft sprocket bolt
Cylinder head bolts

Hope you can help.
Daewoo Nexia Head Gasket - Number_Cruncher
I don't think I dare try to help you - I might be accused of moralising.

Daewoo Nexia Head Gasket - horatio
Thanks for those words of wisdom, now get lost.
Daewoo Nexia Head Gasket - Dynamic Dave
Ok, cut it out, before I get out my scissors and start doing some cutting myself.

Daewoo Nexia Head Gasket - dieselhead
If your unsure as a double check make several corresponding marks between the timing sprockets and engine with typists correction fluid and also on the belt itself ...that way you can count the teeth between the marks on the old belt and transfer them to the new so that you know for certain the timing is the same as before.

You might have to remove the starter and wedge the flywheel if you don't have a nut runner to loosen the crank pulley bolt(s). also ensure the camshaft and crank marks line up (refit cover to check).
Now you need to turn the tensioner until you can insert a locking pin....also you need to loosen the waterpump bolts to adjust the belt tension -this can cause it to leak so you need to replace the seal really if its anything like a vauxhall ..you adjust tension on the belt with the waterpump until the tensioner pointer aligns with a notch...sounds very complicated but it isn't just make sure the timing marks line up and the belt tension is correct.
Not the sort of job you want to be doing if your not experiened in this sort of work. Your best bet would be to get hold of an autodata cd/book which details the job fully... it's just too easy to make a mistake and wreck an engine.best regards
Daewoo Nexia Head Gasket - horatio
Thanks for your comments dieselhead & Steptoe

I don't have a nut runner, (or I think I don't) what is that?

I took your advice of looking for a manual, I found one online but it's all in Romanian! Still it is very useful as it gives diagrams and torques. I will search again for an English version.

For belt tensioning - Interestingly it shows a diagram of the flat faced spindle (I mentioned in OP) next to water pump, it shows this with an "off centre" hexhead bolt and it shows a pointer device and a 'V' notch which you have to line up. (as you said) So I checked my car for a similar pointer and V notch on that spindle and yes they are there. I take your point about loosening the waterpump before tensioning. I see now from the diagrams (and Romanian instructions) that you...
1. loosen the 3 waterpump bolts
2. turn the waterpump till the tensioner lines up
3. tighten the 3 WP bolts

What does it mean, on my car that the pointer and "V" notch are not lined up? The pointer is below the V by about 7mm (belt still fitted), is this showing it was not done correctly at last belt change, or that the belt has stretched a little over time, and the tensioner has taken up the excess play?...If this is the case I think this explains the slight mismatch on the camshaft timing mark?

I wonder, though If when I reassemble (using the old belt), it's difficult to decide what I should do.
A) align the cam-mark exactly as before and re tension the belt pointer to V-notch
B) align the cam-mark exactly as before and retension the belt to where it is now 7mm bellow V-notch
C)align timing marks as they should be, but re tension belt pointer to V - thus taking up the slack in the stretched belt

*The camshaft sprocket mark is currently about 2mm before the mark.

BTW I found the torques as follows:
camshaft sprocket 45 Nm
have not yet found crankshaft pulley torque

CH bolts 25Nm (spiraling inwards)
then 60°
then 60°
then 30°
Because it's in Romanian I think it says do some other stuff like refitting some ancillaries
then another 30°

inlet and exhaust manifolds 25Nm (and it gives the correct order too)

Ok so I'm going to crack on with this now, and remove the crankshaft pulley - I'm going to put it in 4th gear for this, as I read it on t' Internet!

Oh and also, it is a scrap car, I bought for scrap value, has 4 good tyres (fit my other car) and half tank of petrol, I'm just doing this to see if I can get to work again, and pass its MOT then I will keep it for a bit and sell it - if it all goes Pete Tong - no loss, I just scrap it.
Daewoo Nexia Head Gasket - horatio
BTW (by the way)

Here is a pic of timing belt tensioner in Romanian
click the picture to enlarge.

Just wondering if it is saying the first is the position for a new belt the second for a used belt? Or is it saying something else?
Daewoo Nexia Head Gasket - Steptoe
Your concerns at the moment seem to be with the crankshaft pulley rather than the actual head gasket change, so a few general thoughts on this bit;

The timing pointer on the front belt cover will be for the purposes of checking ignition timing rather than belt positioning (think back to the days of swiveling distributers), there *should* be some marking/timing pin hole on the crankshaft sprocket, which is keyed to the crankshaft ( if this is aligned you may find the camshaft mark also lines up).

To check this the crankshaft pulley needs to come off, I bought a 12v impact driver to do this without the hassle of jamming flywheel or putting in gear but have not as yet needed to use this in anger.

Sorry I can't help you with the torque settings but best of luck

One mans junk is another mans treasure
Daewoo Nexia Head Gasket - horatio

Well I didn't get very far today. The crankshaft bolt is too tough, I might give it another go, but I am unable to apply a shock force only able to apply gradual force, and this just takes up the slack in the gear box and then moves the car backwards, until I have no more room to pull.

I noted your comment on the impact wrench, so you have an electric one like these and it works well does it?


I am toying with the idea of buying an air powered one (already have compressor) like one of these cheaper SIP 1/2" ones

Then again I think I will try a manual impact driver first.

Hi Ho.... Hi Ho...
Daewoo Nexia Head Gasket - Steptoe
I bought my 12v impact wrench from Aldi's reasoning that the £12 cost was not a lot to lose if it didn't work.
It looks similar to the Clarks one on the Autoexpess review, but I have not yet had to try it on a crankshaft pulley. It wouldn't undo the very tight wheel nuts on my van though, so I'm not holding my breath!

One tip regarding the car moving backwards; when this happened to me I partially undid two wheel bolts and braced a flat metal bar between these and the ground, this stops the winding-up effect.

One mans junk is another mans treasure
Daewoo Nexia Head Gasket - horatio
Interesting method, to stop roll-back.

I did finally get the crank pulley bolt undone, just needed to adjust the socket on the bar so I could start at an earlier point iyswim. So I don't think I'll get an impact wrench afterall. Torqueing that crank pulley bolt is going to be fun, with the limited space I have under the car.

Right then, update:
With the pulley off, I can now see there is a timing mark on the crank sprocket and a mark on the rear TB cover which it lines up with - so that's ok then.

I can also move the tensioner upwards/clockwise by hand and it releases enough tension to disconnect the belt. I see the holes in the pointer on the tensioner and I think, dieselhead, you are telling me to release the tensioner and lock it in the released position with a pin through the holes. Then remove belt from cam sprocket, go to work on the head gasket, and then I suppose I could just refit the belt, release the tensioner, without moving the waterpump? What do you think about that?

Tomorrow I'll remove the inlet and exhaust. And hopefully the cylinderhead. I am working slowly on this in my spare time.
Daewoo Nexia Head Gasket - RichardW
You're on the right track. Autodata says to remove the belt: turn the tensioner until you can fit a pin in the holes, then remove the belt. Fit the new belt, then remove the pin from the tensioner and release it. Turn the WP clockwise to tension the belt until the pointer hits the stop at the bottom. Nip up the WP bolts and turn the engine over forwards 2 full revs, and check timing marks (top of cam and side of crank sprocket) align, then slacken water pump and turn anti-clock until the tensioner pointer points at the mark above the stop. Tighten the WP and refit the crank pulley. Book time 0.9 hours!!

Is it illogical? It must be Citroen....
Daewoo Nexia Head Gasket - dieselhead
Think it's all been said but do double check the tension/timing marks after turning the engine over a couple of times. It's easiest to engage 5th gear and jack the offside wheel up and turn the engine over on that.
Don't think you would regret buying an impact wrench (SIP are the best you can buy without spending alot more money imho) , go for pneumatic if you have a compressor as the elecric types are less reliable and powerful.

Value my car