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[blue_dream]

Hi
   Can someone please give me some advice, 25  v6 engine, valve timing seems to be out, unable to fire.
   checked cambelt, crank spocket out, took cambelt off, need to change oil seal, on taking main bolt out found that the spocket turns on the end of the crank shaft, no resistence, pulled spocket of, guide had gone inside but must be held by the toque of the bolt
   If i align the spocket and then try to align the cams, valve to piston may stop this, am i right in thinking this is TDC and not BTDC  :-? :-?

[3.2 manual]

not sure what yr asking is the crank seal leaking? also on my 3.2 the crank mark faced down, while the cams faced up. but it may have a keyway or something as i cant believe cam timing is held on a frictional drive, how would you positively locate it? after taking the pulley off?

[Darth Loo-knee]

There should be a woodruff key to locate the crank sprocket onto the crank, without that I would imagine it very difficult to get the crank into the correct position especially when torquing to Mega Tight :-?

[al brown]

Also crank goes round twice to the cams once so you would know if the crank is at TDC or 180* out.
Al

[deviator]

Yeah there should be a woodruff key, I've seen this before, happened to my engine. The bolt worked loose and broke the woodruff key off throwing 24 valves. Might I add according to my manual this bolt needs 250nm of torque on it! Mine has that and then some thread lock to make sure.

To find TDC. Get a new crankshaft pulley and fit it. I had to use a large set of stilsons on the flat sides, locked off against the water pump or ground to get it tight.

With the cam belt off, so all the valves are closed....
1. Take out plug number 1, stick a long screw driver down the hole.
2. Stick a torques socket (I forget the size) on the crankshaft nut (double hex 16mm socket as an alternative) turn the engine until the line is at the bottom and lined up to the notch on the bottom of the oil pump.

At this point the screw driver will be either at it's highest point or lowest point, to confirm turn the engine 360 degrees and see if the screw driver is high or low.

When cylinder 1 is at it's high point, thats TDC.

PS If you are struggling to turn the engine over by hand, take all the plugs out.

[blue_dream]

Hi
  Thanks for coming back guys, keyway broken on crankshaft timing spocket, was taking it of to replace front crankshaft seal and notice no resistence, the bolt was mega tight, used a trolley jack handle on the rachet to undo but cannot understand how this has stayed, must be due to the touque on the bolt , just hope i can get the cams into align along with the spocket
      Thanks again lads 

[3.2 manual]

STOP. is the engine still in time, i mean was it running? when stripped? i ask, as how did the key shear and still be in 'time'. the key must be at least a tooth-wide(at the pulley belt surface) and something sheaered that. but the bolt held it tight after the key was gone. check it, its probably out. but you may have gotten away with it!

[Elite Pete]

STOP. is the engine still in time, i mean was it running? when stripped? i ask as how did the key shear(and still be in 'time') but the bolt held it?

The key shears from the bolt being undone incorrectly, you need to lock the bottom pulley before undoing the bolt.

[3.2 manual]

ah, so it may have been fine before the removal?

[Elite Pete]

ah, so it may have been fine before the removal?

Possibly, I had a 3.0 that was the same, the car was very uneconomical and a bit down on power even though I had changed the cambelt and timed it up properly. When I came to change the front crank oil seal at a later date it turned out that someone had previously had it to bits and used an airgun to take the bolt out shearing the key, they put it back as near as dam it