V6 timing - here we go again!!

[murphyv310]

Originally Posted by hogweed

BANG!!! Pieces of valve and piston everywhere...




Yes, there's a lot to be said for chains...

Until your chain breaks............ Not unknown.

[Mike Noc]

Must admit I've never heard of one breaking on an M47R engine though Trevor, which is good news, as mine have done a fair few miles now.

Originally Posted by Phil-T4

No, they dont always line up perfectly, this is also evident on vehicles that have never had a belt change, the front (LH Bank) is always inline but the rear (RH Bank) isn't, it can be 1/2 or 1 tooth out of alignment with the timing pin is locked into the flywheel.

Having said that, i was in Yorkshire the end of last month and did 2 belts changes whilst i was there (a 177 2.5 and a 190) and on both of them the rear pulley marks aligned perfectly

Another thing to watch for is the mark on the crankpulley isnt always in the correct place, i have come across 2 or 3 where it is 180 degrees out which confused the hell out me at first!

So the note in the Landrover cambelt refitting instructions is quite correct then:

Refit

NOTE: Following front or rear timing belt
refitment, it is possible that, after rotating the
engine and positioning the crankshaft pulley to
the 'SAFE' position, the timing marks on the
rear timing gears may be misaligned. This
misalignment is acceptable provided that the
timing belt refitting procedure was carried out
correctly.


Curiouser and curiouser.


If the alignment of the marks can vary, then it seems the only way to ensure the timing is spot on is to use the tools.

Begs the question where is this variation coming from though?

[murphyv310]

Could it be as simple as the marks on the pulleys are wrong from the factory? Hence the need to time with the tools in the sequence that Rover lay down.

[COLVERT]

Originally Posted by murphyv310

Until your chain breaks............ Not unknown.

Slightly rarer than hens teeth.---

[murphyv310]

Originally Posted by COLVERT

Slightly rarer than hens teeth.---

Neighbours BMW 3 Series with the same basic engine broke a chain at 210,000 miles, granted its rare but can happen, one of the sprockets was badly hooked. Car was sold spares or repair due to the damage done.

[reclamation ray]

Hey Colvert, you know whats going to happen now don't you.LOL

[kaiser]

Originally Posted by Mike Noc

Must admit I've never heard of one breaking on an M47R engine though Trevor, which is good news, as mine have done a fair few miles now.




So the note in the Landrover cambelt refitting instructions is quite correct then:

Refit

NOTE: Following front or rear timing belt
refitment, it is possible that, after rotating the
engine and positioning the crankshaft pulley to
the 'SAFE' position, the timing marks on the
rear timing gears may be misaligned. This
misalignment is acceptable provided that the
timing belt refitting procedure was carried out
correctly.


Curiouser and curiouser.


If the alignment of the marks can vary, then it seems the only way to ensure the timing is spot on is to use the tools.

Begs the question where is this variation coming from though?

This is most likely because finding the safe mark involved a bit of to and fro. So a lot of times the mark (which consists of two holes that have to align) is found by moving the flywheel back and forwards, until the pin fits. That then could include a bit of slack, depending on how the point was found, and the marks can thus be out a small amount.
You of course realize that his inaccuracy has nothing to do with how the marks was found in the first place.! The manual is just warning you not to panic, if the marks are a fraction out, when you find the safe spot again. That would make sense, and I think that is all there is to it.

And of course the marks on the sprockets must align, like on any other car!!
Anything else would be lunacy!

And as for the three different tools, there are at least two different numbers for the sprockets! and two different cams for the various 6 cylinder engines.
That gives 4 combinations!
However if the sprockets are the correct ones for your engine, use the timing marks at the rear for the recommended setting, that is pure logic.

[Phil-T4]

All pulleys (sprockets) are the same regardless of the engine size and power output.

[Phil-T4]

Originally Posted by COLVERT

Slightly rarer than hens teeth.---

[kaiser]

Originally Posted by Phil-T4

All pulleys (sprockets) are the same regardless of the engine size and power output.

that might be, but the spare part numbers are different for the 2 and 2.5 V6! That is what I get if I look at Rimmers.