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#1 jonny d

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Posted 07 May 2007 - 09:53 PM

HI all I would like to know what the clearances are for the inlets/exhaust on
my modified rebuild.Also the timing if poss on crank pulley, at the moment
i have just turned dizzy until it sounds and runs better but when i put a timing
light on it its way below the marks how is this possible?The car starts ok but idles
at 1000rpm any lower and goes all lumpy and cuts out. Help please if you can.
spec
1330
276 cam
standard rockers
oe slipper A+pistons
MG Metro head ported and flowed(60thou skim)additive
yellow dizzy(no vac)
minispares road light flywheel
hif44 carb

#2 *DJH*

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Posted 07 May 2007 - 09:54 PM

A standard setup is 14thou

#3 icklemini

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Posted 07 May 2007 - 10:01 PM

I would like to know what the clearances are for the inlets/exhaust on
my modified rebuild


as you have standard rockers - 12 (tight) to 14 (loose) would be the rocker clearances to aim for...

at the moment
i have just turned dizzy until it sounds and runs better but when i put a timing
light on it its way below the marks how is this possible?

the TDC position is in the correct place on the pully? - (checked during build?)

Edited by icklemini, 07 May 2007 - 10:01 PM.


#4 jonny d

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Posted 07 May 2007 - 10:52 PM

I would like to know what the clearances are for the inlets/exhaust on
my modified rebuild


as you have standard rockers - 12 (tight) to 14 (loose) would be the rocker clearances to aim for...

at the moment
i have just turned dizzy until it sounds and runs better but when i put a timing
light on it its way below the marks how is this possible?

the TDC position is in the correct place on the pully? - (checked during build?)

What do you mean correct on pully it can only be one way cant it?

#5 icklemini

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Posted 07 May 2007 - 11:01 PM

What do you mean correct on pully it can only be one way cant it?

well the pully can only fit on the crank one way, however
what pully is it?
has the crank been reground? - if so was that done right? (can move the true TDC point)

have known the mark on the pully to be a good few degrees out when actually measured against the true TDC point of the engine... all down to tolerances..

ttfn,
Dave

#6 jonny d

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Posted 08 May 2007 - 06:27 PM

What do you mean correct on pully it can only be one way cant it?

well the pully can only fit on the crank one way, however
what pully is it?
has the crank been reground? - if so was that done right? (can move the true TDC point)

have known the mark on the pully to be a good few degrees out when actually measured against the true TDC point of the engine... all down to tolerances..

ttfn,
Dave

The crank has not been reground as far as I know
The pulley is MG Metro

#7 icklemini

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Posted 08 May 2007 - 07:25 PM

well all should be reasonably in the right ball park..

#8 icklemini

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Posted 08 May 2007 - 07:30 PM

i have just turned dizzy until it sounds and runs better but when i put a timing
light on it its way below the marks how is this possible

You will find that the engine will purr along at idle with a load of advance.
What timing are you actually running at idle? it sounds like you have >12degs of advance at 1000rpm - need to measure it and adjust accordingly.. with the Aldon yellow they suggest around 10degs advance at idle though to be honest you may be able to get away with a little more..

another way of setting the advance would be at higher revs - around 4krpm, set the advance then to around 32degs

car starts ok but idles at 1000rpm

doubt you would get much lower on a 276 in a 1330 with distributor ignition.

TTFN.
Dave

#9 jonny d

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Posted 08 May 2007 - 08:02 PM

thanks icklem wow you seem to know your stuff but i don't seem to be able
to get any where near the degree marks by a long way on the strobe light
could i have not put the dizzy drive in right?

#10 icklemini

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Posted 08 May 2007 - 11:09 PM

the dizzy drive could be out, though usually you can turn it (the distributor) quite a way to get the timing... unless the vac advance is hitting the oil pressure take off or similar..

the timing light is connected to #1 lead (the one closest to the rad)??

#11 jonny d

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Posted 09 May 2007 - 06:30 PM

No vac fitted i did the strobe on number 4 could that be my problem?
also lets assume i put the dizzy drive in wrong.would i just turn the
dizzy to correct this?

#12 icklemini

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Posted 09 May 2007 - 07:38 PM

i did the strobe on number 4 could that be my problem?


thats the problem! - you set the timing on lead 1 (the one next to the radiator...)

#13 jonny d

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Posted 09 May 2007 - 10:54 PM

THANKS I will try again on number one and see if the timing marks
come near the ball park figure of 12 degrees as you suggested i will keep you posted
if you don't mind you have been very helpful thanks again.

#14 icklemini

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Posted 09 May 2007 - 11:48 PM

;) - go get it sorted! :P

keep us posted!

(by the way everything else is connected properly? - firing order 1 3 4 2 (1 at rad end, 4 at clutch end) )

all the best,
Dave

#15 jonny d

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Posted 10 May 2007 - 08:37 PM

WELL Dave success at last strobe on no.1 turned dizzy till 12deg turned up idle speed 1100
seems to run ok keeps idle ok so a very big thankyou to you for helping me sort this.




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