Gas shoots out of carb, wont fire

[MitchThor14]

Hello everybody, i have a bit of a problem. When i go to start my truck it cranks and shoots fuel out of the carb but does not fire.

It ran fine yesterday but when i set the valve lash i set it a little too loose (was my first time) so i pulled the covers off and re did it properly. To do that i obviously took the spark plugs out so i had to unhook the wires but i put them back on correctly.

I did not touch a thing other than set the lash, So I'm not sure what i could have done to make this happen. Could the timing be off or something? I'm not sure how because i didn't touch it. Anyways thanks for the help in advance.

It is an 84 C20 305 with a 4 barrel Quadrajet carb.

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[bd]

Recheck the firing order again 1-8-4-3-6-5-7-2, odd cylinders are driver side with #1 at front, even cylinders are passenger side.  How did you go about adjusting the valves?  Sounds like they could be too tight and hanging open.

[MitchThor14]

Recheck the firing order again 1-8-4-3-6-5-7-2, odd cylinders are driver side with #1 at front, even cylinders are passenger side.  How did you go about adjusting the valves?  Sounds like they could be too tight and hanging open.

I dont think they are too tight i followed this 100% http://www.speedwaymotors.com/Tech/how-to-adjust-hydrualic-lift-cam-valve-lash.html


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[bd]

You followed the Exhaust Opening Intake Closing (EOIC) method, which is a very workable procedure.  Nonetheless, people who get into trouble adjusting valves, often get into trouble at the following point regardless of the method they use (excerpted from the procedure you linked)...

• To achieve zero lash, tighten down the rocker as you spin the pushrod in your fingers, do this until you notice slight resistance as you spin the pushrod (this is zero lash). You should also no longer have any lateral movement in the pushrod.
  
• When you know you’ve hit zero lash, tighten the rocker another 1/2 turn to set the optimum preload on the lifter, pushrod and rocker arm.
  

The key phrase is "...do this until you notice slight resistance as you spin the pushrod...."  Unfortunately, that is a very subjective description if ever there was one.  The phrase is way too easy to misinterpret.  Chances are that the "slight resistance" you felt while spinning the pushrod was actually the lifter piston bottoming in the lifter body.  The subsequent additional 1/2 turn actually pushed the valves off of their seats.  Obviously, I cannot assure you that this happened, but it is a common error.

Read the following thread from the linked post, forward:  Bent Intake Valve?  The circumstances vary slightly, but the reasoning still applies.  Pay particular attention to the description of determining "zero lash."  Does any of it sound familiar?

[VileZambonie]

Agreed, make sure you began at TDC compression, back them off and recheck your lash.  A common mistake is to feel for lash while the socket is still pressing down on the rocker, spinning the pushrod can also be misleading. Be sure to feel for movement up and down with the socket removed as you go. If you can't tell, back it off and start again.

[Rattler12]

Anybody else use the  1-6 , 8-5, 4-7, 3-2  etc. method ie adjust # 1 I and E valves  when # 6 I and E lifters are just rocking and so on ?

[gunrac]

Best and quickest way, IMO. Do this moving pushrod up and down checking lash. When you think your close, keep checking lash with the socket off the adjuster nut.

87' repair manual

6A5-34 V8 ENGINE

VALVE ADJUSTMENT

1. Remove the rocker arm covers.
2. Crank the engine until the mark on the torsional
damper lines up with the center or “ 0 ” mark on the
timing tab (figure 72). The engine must be in the
number one firing position. This may be determined
by placing fingers on the number one cylinder’s
valves as the mark on the damper comes near the
“ 0” mark on the crankcase front cover. If the valves
are not moving, the engine is in the number one
firing position. If the valves move as the mark comes
up to the timing tab, the engine is in the number six
firing position and should be turned over one more
time to reach the number one position.
3. With the engine in the number one firing position as
determined above, the following valves may be
adjusted:
— Exhaust - 1, 3, 4, 8
— Intake - 1 , 2, 5, 7
(Even numbered cylinders are in the right
bank; odd numbered cylinders are in the left
bank, when viewed from the rear of the
engine.)
4. Back out the adjusting nut until lash is felt at the
pushrod then turn in the adjusting nut until all lash
is removed. This can be determined by rotating the
pushrod while turning the adjusting nut (figure 73).
When the play has been removed, turn the
adjusting nut in as follows:
— 5.0 L and 5.7 L engines: One full turn.
— 7.4 L engines: 3U turn.
5. Crank the engine one revolution until the pointer “ 0” mark on the crankcase front cover. If the valves
are not moving, the engine is in the number one
firing position. If the valves move as the mark comes
up to the timing tab, the engine is in the number six
firing position and should be turned over one more
time to reach the number one position.
3. With the engine in the number one firing position as
determined above, the following valves may be
adjusted:
— Exhaust - 1, 3, 4, 8
— Intake - 1 , 2, 5, 7
(Even numbered cylinders are in the right
bank; odd numbered cylinders are in the left
bank, when viewed from the rear of the
engine.)
4. Back out the adjusting nut until lash is felt at the
pushrod then turn in the adjusting nut until all lash
is removed. This can be determined by rotating the
pushrod while turning the adjusting nut (figure 73).
When the play has been removed, turn the
adjusting nut in as follows:
— 5.0 L and 5.7 L engines: One full turn.
— 7.4 L engines: 3U turn.
5. Crank the engine one revolution until the pointer
“ 0 ” mark and torsional damper mark are again in
alignment. This is the number six firing position.
With the engine in this position the following valves
may be adjusted:
— Exhaust - 2, 5, 6, 7
— Intake - 3, 4, 6, 8

[SomeTexan]

Man, y'all all do this the hard way. It's really simple. Start engine, remove one valve cover, loosen each rocker until it starts to clatter, tighten until clatter stops, add another 1/4-1/2 turn of preload, repeat on the next 7 valves, replace valve cover, repeat on the other bank. Super easy and it takes 5 min. I've done this on literally hundreds of Chevy engines with zero issues. I was taught to do it that way by an engine builder at Rehr Morrison back when I was 14ish.

[gunrac]

Man, y'all all do this the hard way. It's really simple. Start engine, remove one valve cover, loosen each rocker until it starts to clatter, tighten until clatter stops, add another 1/4-1/2 turn of preload, repeat on the next 7 valves, replace valve cover, repeat on the other bank. Super easy and it takes 5 min. I've done this on literally hundreds of Chevy engines with zero issues. I was taught to do it that way by an engine builder at Rehr Morrison back when I was 14ish.

Ya, I know where your at, been there done that. Reason I went the other way was on my 94' everything hung over the  valve covers. Air and PS both needed to be removed. Getting to them fan an shroud had to go also + couple sensors......wasn't fun. Guess the best part was no oil mess all over to clean up.

[SomeTexan]

Man, y'all all do this the hard way. It's really simple. Start engine, remove one valve cover, loosen each rocker until it starts to clatter, tighten until clatter stops, add another 1/4-1/2 turn of preload, repeat on the next 7 valves, replace valve cover, repeat on the other bank. Super easy and it takes 5 min. I've done this on literally hundreds of Chevy engines with zero issues. I was taught to do it that way by an engine builder at Rehr Morrison back when I was 14ish.

Ya, I know where your at, been there done that. Reason I went the other way was on my 94' everything hung over the  valve covers. Air and PS both needed to be removed. Getting to them fan an shroud had to go also + couple sensors......wasn't fun. Guess the best part was no oil mess all over to clean up.

Good point, I forget about the long a/c compressors that GM used to use. When I was younger, that was the first thing to hit the trash though. If it didn't make power, it wasn't on my vehicles.

[FlatBlack77]

My first time setting valves i did it as said above with the engine not running.

and i ended up setting them way too tight by making the mistakes said above.

and the engine did exactly what MitchThor14's engine is doing lol it would fire here and there but it sounded like a Briggs and Stratton 5horse with a miss and no muffler.

so i set them with the engine running and will never go back