ZERO compression on all 8 cylinders
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Joined: Aug 2003
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From: Hilliard FL
ZERO compression on all 8 cylinders
I went to start my newly rebuilt (i built it) with my old edlebrock carb. Well, the carb was all gummed up and let gas run continuously down the intake. I would guess that a gallon or so went straight into the cylinders before I figured out what was happening.
I went to get #1 piston TDC by putting my finger over the spark plug hole while bumping the starter. Well, It NEVER pushed any air out. So, I went to each of the other cylinders with the same results. :crazy:
I read somewhere that the gas could make the rings unseat, and you should squirt a little oil down the cylinders and let it sit for a couple of hours. I went thru this exercise yesterday and rechecked it today with the same results.
I have tried a little more oil in the cylinders today and will try it again tomorrow.
ANY SUGGESTIONS?
I went to get #1 piston TDC by putting my finger over the spark plug hole while bumping the starter. Well, It NEVER pushed any air out. So, I went to each of the other cylinders with the same results. :crazy:
I read somewhere that the gas could make the rings unseat, and you should squirt a little oil down the cylinders and let it sit for a couple of hours. I went thru this exercise yesterday and rechecked it today with the same results.
I have tried a little more oil in the cylinders today and will try it again tomorrow.
ANY SUGGESTIONS?
Race Director
Joined: Apr 1999
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From: Beverly Hills/Pine Ridge Florida
Re: ZERO compression on all 8 cylinders (zwede)
Drain all the gas contaminated oil and put a new filter on. Don't start the car with the gas diluted oil.
If you squirted oil down each cylinder, you should have compression. The valves could be stuck open/misadjusted holding them open. Are you sure about the ring end gaps on the piston rings??? Did you check for compression before the carb leak? Chuck
If you squirted oil down each cylinder, you should have compression. The valves could be stuck open/misadjusted holding them open. Are you sure about the ring end gaps on the piston rings??? Did you check for compression before the carb leak? Chuck
Melting Slicks
Joined: Jun 2002
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From: Orrtanna Pa.
Re: ZERO compression on all 8 cylinders (73Gator)
Make sure the throttle is open(stick a screw driver in the carb to hold the throttle plates open) and remove all the spark plugs to eliminate excessive strain on the starter and battery.If you still don't get decent compression check the valve lash,and verify the distributer rotor is turning.
Good luck!
Good luck!
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From: Hilliard FL
Re: ZERO compression on all 8 cylinders (Chuck Gongloff)
I will change the oil and filter before starting the engine.
I was very carefull with the ring end gaps.
I did not check the compression before the carb leak
I will go out and remove the rocker arms on #1 and see what I get.
I was very carefull with the ring end gaps.
I did not check the compression before the carb leak
I will go out and remove the rocker arms on #1 and see what I get.
Burning Brakes
Joined: Apr 2004
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Re: ZERO compression on all 8 cylinders (73Gator)
Nope....Pulled valve covers and they are rocking as they should.
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Burning Brakes
Joined: Feb 2004
Posts: 958
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From: In the Beautiful Shenandoah Valley of VA
Re: ZERO compression on all 8 cylinders (73Gator)
I would suggest that you double check your valve adjustment, since you just assembled the engine. This is the same outcome I had on my '74 LS-4 I purchased after an unknowing mechanic "adjusted" the hydraulic valves during a "tune-up" by cranking all of the rocker arms down as far as they would go. And then cranking the engine over. Every intake valve was bent and every intake pushrod was bent or broken resulting in no compression. I'm not suggesting that you might have bent the valves, but they might be held open from an incorrectly performed valve adjustment, thus causing a no compression situation.
I seriously doubt that gasoline through the cylinders would stick the rings and cause no compression, but stranger things have happened.
Steve
I seriously doubt that gasoline through the cylinders would stick the rings and cause no compression, but stranger things have happened.
Steve
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Re: ZERO compression on all 8 cylinders (Steve's74)
A friend of mine had a similar problem, but only one cylinder had zero compression. Turned out to be the rocker arm stud on that cylinder was not the same as the other 7. It was too short and wasn't allowing the valves to close all the way
Team Owner
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From: eville in
Re: ZERO compression on all 8 cylinders (coldwarrior2000)
with the carb throttle plates open (floored) when cranking (ign disabled) listen
in carb for lost compression, stuck intakes, i have taken rockers off all valve's and used a plastic mallet to rap each one (not to hard) and had it free up the carbon and or varnish the was causing things to stick
in carb for lost compression, stuck intakes, i have taken rockers off all valve's and used a plastic mallet to rap each one (not to hard) and had it free up the carbon and or varnish the was causing things to stick
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Joined: Aug 2003
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From: Hilliard FL
Re: ZERO compression on all 8 cylinders (73Gator)
Time to remove the ADULT BEVERAGE cart from the garage.
I had to have one too many adult beverages when I was adjusting the valves.
EVERY ONE of them was screwed up.
Thanks to you guys for making me see the light.
I'm just glad that that was all it was! :party:
Got to change the oil and rebuild the carb and I will light that baby off! (hopefully)
Thanks again guys!!!!!!!
I had to have one too many adult beverages when I was adjusting the valves.
EVERY ONE of them was screwed up.
Thanks to you guys for making me see the light.
I'm just glad that that was all it was! :party:
Got to change the oil and rebuild the carb and I will light that baby off! (hopefully)
Thanks again guys!!!!!!!
Race Director
Joined: Apr 2000
Posts: 17,676
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Re: ZERO compression on all 8 cylinders (Gordonm)
Cocktails and engine work can get very expensive, reminds me of a little story, oh never mind, glad you got it worked out :lol:
[Modified by MotorHead, 6:06 PM 4/26/2004]
[Modified by MotorHead, 6:06 PM 4/26/2004]
Racer
Joined: Apr 2004
Posts: 271
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From: Alpharette GA
Re: ZERO compression on all 8 cylinders (73Gator)
Been their done that!!! Check the valve lash more than likely all your valves are not seating on the CP stroke. Take them back to zero lash and you'll have compression. At zero lash tighten 1/2 turn for a 20 pre load on a 350. :smash:
OPPS Sorry did not see you post about Adult beverage before my post.
[Modified by checklst, 12:13 AM 4/27/2004]
OPPS Sorry did not see you post about Adult beverage before my post.
[Modified by checklst, 12:13 AM 4/27/2004]
Race Director
Joined: Apr 1999
Posts: 10,866
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From: Beverly Hills/Pine Ridge Florida
Re: ZERO compression on all 8 cylinders (checklst)
Reminds me of my buddy's 327/300 for his 64 a few years ago. He got it back from the machine shop, completely assembled, heads and all. Was told everything was "adjusted and ready to fire up".
We put the motor/trans in the car, and hooked everything up. After fooling with it for an hour and having no luck starting it, we reluctantly removed the freshly painted "engine orange" valve covers, getting some paint curls on the fresh paint. Whoever adjusted the valves was either having a bad day, or was clueless about valve adjustments.
After correctly resetting all 16....it fired right up. My bud was NOT real happy with the machine shop, and had a few words for them which I cannot repeat here. :) Chuck
We put the motor/trans in the car, and hooked everything up. After fooling with it for an hour and having no luck starting it, we reluctantly removed the freshly painted "engine orange" valve covers, getting some paint curls on the fresh paint. Whoever adjusted the valves was either having a bad day, or was clueless about valve adjustments.
After correctly resetting all 16....it fired right up. My bud was NOT real happy with the machine shop, and had a few words for them which I cannot repeat here. :) Chuck