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Major Timing Or Compression Problem

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Old Oct 6, 2003 | 09:16 PM
  #1  
MY91Y84's Avatar
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From: Just outside of "D-town"
Major Timing Or Compression Problem

ok guys, after my car has been sitting on jackstand since april i finally got ready to fire the motor for the first time...put the carb on, primed the bowls since they were empty and cranked her over...BOOOOM...at first i thought a shotgun went off, but it was the loudest backfire i have ever heard...right out the open header...after my ears stopped ringing, we tried again..BOOOOOM another one...again after gettin my hearing back i took the distributor out and put it back in 180 degrees.....primied up the bowls and cranked again...a little cough, hickup and then it back fired slightly through the carb igniting the unburnt ful on the main body....so we played with time a little and no difference..still wont crank over..but it coughs and hicups....i pulled out the number one plug to find the compression stroke and i didnt feel anything..i mean nothing at all...so now im really starting to worry...
when i was building the motor i made sure before i dropped it in that it had compression...i didnt do a compression check then...when i manually turned the motor over i heard the compression blow out the exhaust ports.....

when i crank it over with the starter it doesnt sound like the motor is compressing...kinda like its just spinning it over ya know...
i had my buddy tw me home and when i was i put it in 3rd and let the clutch out...and when it was turning over you could feel the pulse in the exhaust form the compression......


im really very close to getting this POS going..and im getting a littel frustrated with this [crap]...

does it sound like the compression is gone or the timing is out?.....but even with the timing out a little it should still fire...

im really stumped guys...


BTW..this is a 94 shortblock with LT4 heads

Last edited by Injuneer; Oct 6, 2003 at 10:23 PM.
Old Oct 6, 2003 | 10:00 PM
  #2  
wrencher's Avatar
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From: Chicago Illinois
Sure the timing chain is on correctly?

Get a compression gauge & check all the cylinders.

If ok then turn the motor over by hand w/#1 plug out.

When you hear air come out off plug hole, line balancer up on TDC.

Then install distributor on #1.
Old Oct 6, 2003 | 10:26 PM
  #3  
MY91Y84's Avatar
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From: Just outside of "D-town"
thats another thing...the cam never came out...so its still set were it was from the factory...i took the chain off, but im 100% positive it went back on the same way
Old Oct 7, 2003 | 02:36 PM
  #4  
MY91Y84's Avatar
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Joined: Jun 2003
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From: Just outside of "D-town"
ok i loosend the rockers and i could visably see the springs coming up...i got them all loosend up and took out the distributor out found #1 compression and put it back in...primed the carb and BOOOOOM she fired right up =)..but i have another problem...

when i key up the FP comes on and primes it up or whatever...when i crank it the the pump pumps a little and when it fires the pump doesnt pump anymore...so i have to run a wire from the 12v on/off to the fuel pump soleniod under that back seat right?....so that whenthe key is on the fuel pump will be on...and could i put a switch in-line so i can have the ignition on but flip the switch when im ready for fuel?...

thanks for the help guys

Rob
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