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Discussion Starter #1
Hey all, im stuck and need some advice again! :roll:

Problem is that i have taken the cylinder head off because of a valve going, started putting it all back together & about to put the 2 camshafts back on again but there doesnt appear to be enough of the timing chain to get around the 2 sprockets...?! I believe the timing cover has a 'shoulder' to prevent the chain coming off of the crankshaft sprocket but is it possible for the chain to have slipped around and have slack trapped underneath the crankshaft sprocket? If so how do I remedy this problem?
 

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Have you removed the tensioner? - I'ts usual practice to fit the sprockets to the chain and then fit the sprockets to the camshaft rather than try to lift the chain over the sprokets while they are on the cams.
 

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Discussion Starter #3
yeh the tensioner is removed... Is it just an optical illusion and will the chain fit then if I take the sprockets off?!?
 

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When I did my headgasket I just left the chain on the procket and screwed the sprocket back on with the chain on it. You have to be really carefull that the sump and the camshaft are still in the same identical positions as they were when you pulled them appart or the valves will hit the pistons, but i spose u knew that :cheesy:
 

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Discussion Starter #5
yeh i timed it all up before i started taking anythin apart... But im still left with my problem! :eek: Im gonna go take the sprockets off and try that after lunch but if that don't work anyone got any other ideas?
 

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If there's slack timing chain bunched and trapped down at the crankshaft sprocket then you've got real problems :eek: With the chain tensioned (bungee cord or something) you could try rotating the crank just a smidge (breaker bar + 30mm socketon the crank pulley bolt) to loosen the chain. Whatever happens, the chain must not be allowed to slip off the crank sprocket.

With the head off the block, or indeed with the timing chain off the sprockets, you're supposed to keep the chain fairly taut. Using a bungee cord works well.

If you put the sprockets on the cam, you won't then be able to wind the chain onto the sprockets - there's just not enough slack. IIRC you have to put the chain onto the sprocket, and then bolt it to the cam.

The bold text below might help:
Tom Townsend said:
To set the engine in time, again recheck the crank timing via the pointer and degree wheel on the flywheel. It should point exactly at 0. Pull the chain up tight from the bottom (exhaust) side of the engine and start the cam gear for the exhaust cam in the chain. Be careful not to pull the chain so hard as to turn the crank, keep a constant check on the flywheel marks. I find it easier to turn the exhaust cam back counterclockwise just a hair off its mark.

Then install the exhaust cam gear on the cam, making sure its notch fits in the groove in the cam. Make sure the line on the cam gear is perpendicular to the head. If you turned the cam counterclockwise, bring it back so that the line on the gear is perpendicular to the head, making sure doing so does not move the crankshaft. Recheck the flywheel marks. This little bit of movement makes it easier to align the cam and gear with each other and still keep a tight chain. You just have to make sure the crank doesn't move off 0 when doing it.

Start the 14 mm bolt in the exhaust cam holding the gear on but do not tighten it yet. Pull the chain over the intake cam gear, getting the line on the gear close to perpendicular with the head. I also turn the intake a bit counterclockwise to ease in the mating of cam to gear. Pull the cam back to its marks after slipping the gear onto it.

When the gear goes on the cam, make sure all the marks line up still, the crank with the flywheel mark and pointer and that each line on the cam gears is perpendicular to the head. You can double check the cams by looking at the mark on them and the pointer on the first bearing cap. They should be close, but often aren't dead on. Using these marks alone to time the engine sometimes leads to a cam being a tooth off and a rough idle will result.

I have yet failed to get an engine in time correctly by using the marks on the gears perpendicular to the head. The small radius at the cam leaves too much room for error where the line on the bigger diameter gear is both easier to see and has less room for error.

If you have a lot of trouble getting a cam gear on the cam or seem to have too short a chain, double check the timing marks and insure that the chain isn't folded or in a bind in its guides.

Rocking the crank back and forth via a screwdriver on the flywheel teeth will usually free up a bound or folded chain. Just be extremely careful not to force the engine to turn, you may be bending a valve. If you get something you can't get loose, it is cheaper to remove the head to free the chain than to replace bent valves.
http://townsendimports.com/Web/engine_folder/headgasket90016v.htm

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Discussion Starter #7
Success!!!

Thanks for that info... IT WORKED SUPERBLY!!! Woohoo there is light at the end of the tunnel! :cheesy:
Im now slinging it all back together & was just wondering what the torque are for the bearing cap's?

Thanks again guy's

Jon
 

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Discussion Starter #9
Yeh will do! My good old fashioned Haynes manual told me about them but failed to mention the torque settings i needed...

Thanks :)
 
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