400 smallblock... retarded?
Thread Starter
Teching In
Joined: Nov 2012
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400 smallblock... retarded? So I purchased a 400 sbc from a friend of mine originally out of a 72 impala... its now in my 86 montecarlo
So we button her up, go to crank her and heres what I get
we go to crank it and gas comes gushing out of the top of the carb
Intake is BLOWING air and not sucking, so we threw the compression checker on it and, cylinder #1 has 0 compression cylinder #2 30
I was wondering if anyone had any ideas about this, I was thinking it was an improperly positioned camshaft but I would appreciate your input guys
thanks, Josh
So we button her up, go to crank her and heres what I get
we go to crank it and gas comes gushing out of the top of the carb
Intake is BLOWING air and not sucking, so we threw the compression checker on it and, cylinder #1 has 0 compression cylinder #2 30
I was wondering if anyone had any ideas about this, I was thinking it was an improperly positioned camshaft but I would appreciate your input guys
thanks, Josh
Last edited by Josh Hopkins; Nov 5, 2012 at 02:19 PM.
Launching!
Joined: May 2012
Posts: 209
Likes: 1
From: NC
I'd put the motor on #1, watch for the intake valve to open and as you approach TDC watch to see if the intake valve closes BTDC as you continue to rise to TDC. Once you reach TDC see if you can feel the top of the piston. Both valves should be closed at TDC. If this is not the valve event order that you are experiencing then something is definitely not right.
If this is the correct valve event that you see i would verify solid roller or hydraulic, and test to see what pushrod lengths are installed. I would also do a leak down test and determine if the valve seats or valve seals are to blame.
If this is the correct valve event that you see i would verify solid roller or hydraulic, and test to see what pushrod lengths are installed. I would also do a leak down test and determine if the valve seats or valve seals are to blame.
How long has it been sitting. Valves may be stuck in the open position. What do the rest of the cylinders check at? If they are normal, 140-160, then you most likely have valve problems.
Thread Starter
Teching In
Joined: Nov 2012
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Its up at a shop now, I just couldn't figure it out because I dont have much experience building motors so internally speaking about a motor is like me talking about how much i love the dodge caravan
