OK hers the prob I got a 89 blazer with the 4,3 vortec and I managed to
get the TBI to put fuel out and I have goten spark . The prior owner has
put a timing chain in it so I pulled the valve cover and turned the motar
and it seems to be in the right timing order--- The intake valve shuts
just as the piston comes to top dead center-- So after all this I am
s6till wondering why it wont start.. I have also unpluger the distributer
and reset It and then pluged it back in .. I was told it would make a
differance .. Please help me
You mean the motor has been apart just before it was sold and you've never
seen it run since it's been back together? The intake valve can be closed at
TDC as well the top of the exhaust stroke. You need to find TDC by
aligining the groove on the balancer with the 0 degrees index on the timing
chain cover with both valves being closed on number one. At this point you
can then insure the distributor is properly indexed to the #1 position.
Something is out of time because the intake fully closes well before
TDC on the compression stroke. (somewhere between 100 and 120 BTDC)
Sounds like cam is out of time if you are checking it correctly. This
would definately keep it from starting and running.
alright...i just rebuilt my 89....if u have a diagram u can see they
made these things for retards to put back together....if the cam and
crank are aligned correctly there should be two dots that match up one
on top of the opther like this: top dot on the cam gear and bottom on
the crank gear........have a nice day man.......
Ok well i took the front of the motar apart and it apears that the timing
chain and the gears line up properly ( as diagram in chiltons).I i do need
to adjust the distriburor a bit but i will have to do that tomorow.I was
sick all day and had to stop ill put it back together and ill see what
happenes Thanks for the advice.
YOu know after thinking about this somemore I am wondering if you were
rotating the engine bacwards and 360 degrees out of sync with timing
(720 degrees to a complete cycle). If you did it would make sence that
you saw the intake valve just closing because when spun the other
direction it would just be starting to open to draw mixuter in to
compress it during the next 360 degrees of revolution. This would mean
timing was exactly 360 degrees off (180 related to cam) and had no
mixture to ignite so it would not even to begin to try to fire because
it would be trying to "light" empty uncompressed cylinders.
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