Rover 75 Contemporary 2.5 v6 Tourer , crankshaft sprocket removal problem

[mgbsw]

I am in the process of changing the 3 timing belts on my car and have spotted
oil just below the crankshaft sprocket so decided to remove the sprocket and replace the crankshaft oil seal.
But the sprocket seems to be fused to the crankshaft as it will not slide off of the shaft as the RAVE CD and Haynes manuals suggest. I then tried using a hub puller but had to stop as I was in danger of breaking the legs of the puller.
There are two threaded holes on the face of the sprocket which serve no purpose that I can see as the pulley is held hard against the sprocket by a large single bolt. Someone suggested that these two extra bolt holes may be used to prise the sprocket off of the shaft if two long bolts were inserted into these holes and turned clockwise in equal amounts but I cannot see what the bolts would bear against to 'jack' the sprocket off of the crankshaft.
So I am stuck now as I have no idea how to remove the sprocket short of carefully cutting it and cracking it open. The sprocket is available on-line if that is the only option but I would be interested to hear if anyone else has had this problem.

[Salad-Dodger]

Sometimes that sprocket just falls off, and sometimes you will need to use a harmonic puller. Its as easy as pie with the right tool. Don't hit it as they are quite easily damaged. Two bolts pass through the puller plate and screw into those two holes. You leave the bolt in the crank and do up the bolt on the puller. You could try using a couple of long bolts and give it a wriggle but
have a look at this.
http://www.ebay.co.uk/itm/HEAVY-DUTY-13PC-HARMONIC-BALANCE-CRANKSHAFT-GEAR-PULLEY-PULLER-FLYWHEEL-BALANCER-/281649213730?pt=LH_DefaultDomain_3&hash=item419399f122

Steve

[mgbsw]

Hello Steve
Thank you for your help with this. I have just ordered the puller you linked me to on eBay so I will do nothing more until I receive it. Will update you on progress.
Rgds
Mike

[Salad-Dodger]

Hiya Mike.
You have been really unlucky. I have just finished an engine swap on my 190.
One sprocket practically fell off and the other, I had to use the puller. You could make something to do it if you have a vice, a drill and a piece of metal but I have a puller that gets anything off, and its just a slightly larger version of the tool you are buying.
I bought mine a few years ago and I have probably only used it a few times.
You may have to use some spacers/washers on the bolts that you will screw into the sprocket to get the drag on it that you need but its a very easy operation really. Steve

[mgbsw]

Steve,

Just wanted to let you know that the harmonic puller you suggested to me worked a treat, The sprocket came off without a whimper so thanks for your assistance.

Whilst I am here I wanted to ask you if you are aware of any manufacturing issues Rover may have had in their dying days related to this crankshaft sprocket and pulley and if they pinched bits from the production line of other cars. The reason I ask is that on my car the sprocket and pulley timing marks don't match with :-
a) each other
b) the SAFE mark on the engine front plate.

When I first started this job I tried to get all 3 timing reference points to match , namely that:-
1) the timing pin would locate properly in the drive plate hole
2) the SAFE mark on the crankshaft pulley was positioned next to the SAFE mark on the engine front cover plate
3) the rear sprocket timing marks pointed towards each other.
But I could not get all 3 conditions met. When the pulley SAFE mark aligns with the engine plate , the other two (1 and 3 above) were completely off. In the end I decided to ignore the marks on the crankshaft pulley and set the engine up so that the timing pin located properly and the rear sprocket marks matched. The timing belt is now off and as it was removed , both front camshaft sprockets rotated under the action of valve spring pressure in exactly the way the Haynes manual shows so I am absolutely certain I have the engine in the SAFE position in spite of what the crank pulley shows ! Incidentally whilst I have the engine in my 'SAFE' position the SAFE mark on this pulley was currently pointing vertically down (at 6 o'clock position). This is important for the next point...

OK...so now back to the sprocket which I have removed...
When I look at it carefully I can see a small cut-out on its rim which is approx 130 degrees anti-clockwise around from the 6 o'clock position. This cut-out can't be seen when the pulley is still bolted to the crankshaft. I wondered if this was the true SAFE mark to use , not the pulley SAFE mark , but when I loosely re-fitted the engine front plate and loosely re-fitted the crankshaft sprocket again..still no match , the mark is off by about 20 degrees. So I am really puzzled by this and if you or anyone else can shed some light on this I will be very relieved.

Incidentally , I am aware that for every 2 revolutions of the crankshaft , the camshafts rotate through 1 revolution so I have been careful to ensure that I have considered this when setting up my engine.

Look forward to any input you can give me on this issue.

Regards

Mike

[Salad-Dodger]

Hiya Mike. Glad to see you got it all in bits just like me!
The timing mark issue is a common one. You will never get the rear sprockets to aline with the marks on the front of the engine.
Leave the rears alone till you have finished all the work on the front. The real part of the timing is the relation between the inlet cams and the exhaust cams themselves and as the rear sprockets are keyed to the camshafts, there's not much chance of you getting it wrong!
Assuming you haven't undone the sprocket bolts on the front of the engine, all will be well. especially if you don't have the timing tools!

Starting with the crank. Its not uncommon for the mark on the belt sprocket to not line up with the oil pump tab when the pin is inserted through the rear into the flywheel. There's a plate on the back of it that's spot-welded onto it and the accuracy of the position is often a bit off. When you have the pin in there, check the position of the rear sprockets. Although the marks on the rears won't probably line up exactly, they should be very local to each other. If they are on the outside, you are a revolution out.
Use the pin through to the flywheel as god. That's the starting point.
Its a very good idea to mark the sprockets with say tippex before taking anything apart. There's a lot of information on this procedure on this forum and if you put it into google you will find a lot more.
http://forums.xpowerforums.com/showthread.php?t=60892
then there's this one.
http://www.landyzone.co.uk/land-rover/freelander-kv6-cambelt.176621/
And from our own place.
http://www.the75andztclub.co.uk/forum/showthread.php?t=204919&highlight=cambelt+change
It will be much better if you read all you can rather than me to duplicate what's there already. Please come back if you get stuck, but I've a feeling that you will be ok. Steve