How to time an m42?

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Ammaco
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Mon Aug 27, 2007 4:45 pm

ok so after rebuilding my head i think i have made a mistake re-timing my m42. As this was my first time trying this im guessing i probably did.

Can anyone talk me through how to do it properly. Do i have to take the head off again or is there another way i can make sure it is set to TDC?

Basically if someone could tell me how to find TDC, how the camshafts should be placed at TDC, and how many rivets show be between the sprokect arrows (ive heard 15 is correct?

Any help will be greatly appreciated. thanks
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Ammaco
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Mon Aug 27, 2007 7:01 pm

^^^
Chris-W
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Mon Aug 27, 2007 7:04 pm

Use a cam locking tool - only reliable way.
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Ammaco
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Mon Aug 27, 2007 7:21 pm

can u suggest where i can get one of these tools? never used one before.

Still need to know how to find TDC and how to put the cams in though!

can i find TDC without removing the head?
DanThe
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Mon Aug 27, 2007 7:28 pm

Not being funny but if you dont know how to find TDC you shouldnt really be messing

Look on eBay for the tools, they are expensive, but not as expensive as the dealers :eek:
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Ammaco
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Mon Aug 27, 2007 8:21 pm

well to be honest the only way to learn is to muck in, ive already replaced all gaskets, had head pressure tested and skimmed and put all back together. So i can work a spanner.

Just have no experience timing an engine as ive never done one before, hence why im on here looking for advice. So any help would be aprreciated
Ant
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Mon Aug 27, 2007 8:35 pm

you really do need the cam holding tool dude, its the only method to do the job and reliably getboth cams , the bottom end and the camchain tension all setup in one go.

The bottom end can be held in place @ TDC with an 8mm drill bit inserted in the hole by the starter motor, the cams could be eyballed to TDC using a set square but you'll need to hold the whole shabang in place to pop the tensioner and get the timing 100%

ECP sell the tool, £75 iiirc , I believe there's a template for it in the Bentley manual though..

if in doubt go cap in hand to the dealer and borrow/hire theirs, its not a dialy use item so I'm sure they'll oblige

A large deposit will secure ANY tool for my local 5 dealers, subject to availability of course

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Ammaco
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Mon Aug 27, 2007 9:33 pm

Thanks for the help ant. I think im gona get a mate to help me with this. Can someone just answer me this simple question: Is it possible to correctly time the engine by just removing the rocker cover and upper and lover timing case covers?

Or do i have to pull the cylinder head off? thanks
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Mon Aug 27, 2007 9:43 pm

No need to pull the head off, just do what Ant says above.
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Ammaco
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Mon Aug 27, 2007 9:56 pm

perfect. Thanks guys, will let you know how i get on
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