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#16 Shifty

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Posted 07 March 2013 - 11:27 PM

As I recall(which could be wrong!!)

Remove the rocker cover and turn the engine until the valves on no4 cylinder are rocking on open, ie pushed down. Thats pretty much tdc.

(Mra/doug feel free to correct me!!)

#17 o0OWILKSO0o

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Posted 07 March 2013 - 11:31 PM

Guys just come over to Germany and you can do it for me, I'll provide tea, biscuits and a none fritzel-style cellar.

#18 Artful Dodger

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Posted 07 March 2013 - 11:32 PM

Late to the party shifty... ;)

And that's more crude surely? With the screwdriver tactic you at least have time knowledge on approx position. The timing on that engine may be well out and you could end up having a very wrong reading:P

But then again, to do it right, head off and use a DTI.







But the screwdriver is normally called a Northen DTI guage down here anyways ;) (awaits a northerner to arrive)

#19 Artful Dodger

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Posted 07 March 2013 - 11:32 PM

Can I have a ride in the tank?

#20 Shifty

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Posted 07 March 2013 - 11:33 PM

Late to the party shifty... ;)

And that's more crude surely? With the screwdriver tactic you at least have time knowledge on approx position. The timing on that engine may be well out and you could end up having a very wrong reading:P

But then again, to do it right, head off and use a DTI.







But the screwdriver is normally called a Northen DTI guage down here anyways ;) (awaits a northerner to arrive)



Hmm, anyone else think 'Fartfull Fudger' Has a nice ring to it?

#21 Artful Dodger

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Posted 07 March 2013 - 11:34 PM

NO


NONONO ONONONOOOOO


il be good I swear!

#22 o0OWILKSO0o

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Posted 07 March 2013 - 11:35 PM

Can I have a ride in the tank?


If we can find one that runs, bloody squadies spend more time playing with minis than tanks.

#23 MRA

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Posted 07 March 2013 - 11:41 PM

As I recall(which could be wrong!!)

Remove the rocker cover and turn the engine until the valves on no4 cylinder are rocking on open, ie pushed down. Thats pretty much tdc.

(Mra/doug feel free to correct me!!)


Ok ;-) ... tdc is when the piston is at true TDC in other words crank angle is 0 degrees as in vertical (in the A series) it is neither up nor down.... to find the firing stroke on no 1 then both valves need to be loose as well as the crank / piston at TDC

#24 Shifty

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Posted 07 March 2013 - 11:42 PM


As I recall(which could be wrong!!)

Remove the rocker cover and turn the engine until the valves on no4 cylinder are rocking on open, ie pushed down. Thats pretty much tdc.

(Mra/doug feel free to correct me!!)


Ok ;-) ... tdc is when the piston is at true TDC in other words crank angle is 0 degrees as in vertical (in the A series) it is neither up nor down.... to find the firing stroke on no 1 then both valves need to be loose as well as the crank / piston at TDC


So I was right then??

#25 MRA

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Posted 08 March 2013 - 12:08 AM

not really, that would be the ,power cycle (suck, squeeze, bang, blow) and the valves would be closed, the rockers would be loose not pushed down, you would be able to move the rockers though :-)

Sorry Sean :-(

Edited by mra-minis.co.uk, 08 March 2013 - 12:28 AM.


#26 MRA

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Posted 08 March 2013 - 12:27 AM

Guys just come over to Germany and you can do it for me, I'll provide tea, biscuits and a none fritzel-style cellar.


Ive seen where you are .... Are you with 19 regiment ?

#27 MRA

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Posted 08 March 2013 - 12:40 AM

Yes but that only assists in finding TDC, the rockers being loose can be quite a wide range of crank angle....

#28 MRA

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Posted 08 March 2013 - 01:03 AM

Yes I see know, my mistake, however this will still not be TDC. this will indicate the start of the intake cycle.

There are only 2 TDC's on a 4 stroke cycle, one for cylinders 1 & 4 the other for cyclinders 2 & 3, unless you have one of DV's special crankshafts.

Using the position of the valves to gauge TDC is only a rough guess.

#29 MRA

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Posted 08 March 2013 - 01:25 AM

agreed in normal situations..... however the OP will struggle to get a timing light to work if he can't get the engine to start, and it really is fairly important to get it as close as possible before starting the engine.

#30 Gr4h4m

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Posted 08 March 2013 - 07:25 AM

How do you find tdc on a new engine build, when you don't have a cam installed yet, and you want the correct tdc?





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