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Timing the 8 valve.
#1
I have looked at a few threads her and I'm now confused. After reviewing the timing belt thread I thought I was on the right track. Then I looked at how to time the distributor and was lost. The timing belt thread said to time from number 4 like it was number one. Then I looked at the distributor timing post and it said it should point to the number one post. So here is my question with all marks at 12 o'clock should the distributor point to number 4 or number 1 on the cap? If anyone has a link to a illustration that shows all three both timing marks and the distributor location that would be great.HuhHuh 92 geo tracker 8 valve.
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#2
THE CAM IS TIMED AT #4 FIRING
THE DISTRIB ON ALL CARS #1
just forget the distributor.
time the cam. ( perfectly)
now time the distrib. it's timed at #1 firing.

the cam drives the distrib. so the distrib is never going to work if the cam is timed wrong.

btw , the cam mark is at 6pm firing #1, and there are on marks there, for that, see, because its timed at #4 firing.

your wish for all at once does not exist.

but if you wanted to, you could time the cam at #4 (12pm on cam is that, cant make it differerent) the time the distributor to #4 firing,
there is no compelling reason to do that. 1,3,4,2 firing order, so the rotor 180 degrees from #1 on the cap.

cam the distrib.
there are like 10 ways to mess it up.. sadly.
but if all parts are good. no stripped keys, no false marks.or china rotors that fit 3 ways, all plays easy
http://www.fixkick.com
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#3
complicating this is the fact that the distributor can be timed with the rotor at any PM "clocked"position (landing on a cap terminal of course)

the ECU nor Distrib. has no idea what cylinder is wired up.
only combustion knows. (grin)
the factory way of doing this makes the (primary) harness fit right and not be tight or missing the connection totally , Imagine it not connecting to the back side,, oops...

this is the factory way.... the last photo shows the 8v timed the factory way.


[Image: firing8v.jpg]

[Image: dizzy91-real1w.jpg]

confusing all this , is the FSM book, tells you to put the rotor to #1 firing many times.. (eg. setting lash is one)
and if the owner thinks his custom firing is factory HV wiring bam, you just set the valves wrong.
but if you follow the #1 high voltage wire, to find the #1 true cap location, all is well.....

get cam right first. its timed at #4 ,
then put the cam and crank to #1 firing. (#1 valve lash is loose, is just that, unless lash is all wrong. and will be. of the belt is done by factory way.)
drop the dizzy in its hole , until the rotor matches the above photo. bingo it runs.,
now do the strobe light fine adjustments with the engine running hot and timing freeze jump inserted into the DLC



the 8v timing belt is set with lash adjusters loose. so that the tension is correct. this is because the valve bias is very strong and unbalanced on the 8v, (not true on 16v)
if done wrongly, the belt will be too loose. (due to this bias effect) on the extra 16v the springs balance each other out.



on your engine, the cam cog has 2 marks one is false (older engines have just 1 pimple)
this photo makes this very clear. "80C is wrong"

[Image: 8v-cam-cog-close.jpg]


I do the cam first. then do compression test 150psi + good. ( this audit step proves cam time right) { even doing just #1 and going, I didnt mess up , really helps now}
and make sure the crank cog bolt 17mm hex head is at 94 ft/lbs.
if all that passes muster.
now the distributor is ready (for planting)

also
there is no reason at all even to think what cylinder is firing doing the cam.
you just set the marks and time it, (the #4 fact is only a side comment and not important to the steps at ALL)

the reasons its mention at all, is for the mech to be aware of this fact.
say , you notice, OMG, it not at #4, oops cam cog key sheared, or crank key sheared or PO set cam cog to false keys, or?
and the #4 fact, means not looking at the distributor at all, just watch the cam, to find the #4, not the distributor its now all wrong in many cases...

the cam watching is the #4 (2)lobes and valve actions and last if set right)
you see cam go,, intake, compression, firing, power stroke , then exhaust. (valve action) (seen at the belt tensioning step, clearly this action)
this tells you the cam is working right. nothing else
the lash procedure does that too...
after setting any cam, for sure twin cams, i roll the engine by hand spark plugs out. then watch that cam action, (critical im am that it working right)
on twin cam engine not doing that risks bent valves.
so do that on all engines.

btw, the white mark above , when at 6pm is #1 firing.... (fact)

1,3,4,2
12pm ,3pm, 6pm, 9pm (white mark actions) if not stop and correct this error.

i do the audits on all engines, saving bent valves on new engines, and wasted efforts on distributor timing, when there is no hope at all there.
http://www.fixkick.com
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