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darkstar_one

Registered User
Dudes, fired up the t-bird today, idleing crappy, turns out no pressure on cylinder number 3, we changed the spark plugs, wire, injector, and finally did a pressure test, ZERO PRESSURE, im calling the machine shop monday morning to see what they are going to do about it, they probably didnt seat the valves rights :( makes you just want to junk this crap!
 
i honestly feel like just calling it quits... nothing ever works out for me, i give and i give and i give, and for what? NO PRESSURE ON CYLINDER 3! I hope death is easy cuz my life is hard! :eek:
 
i pulled the rocker covers and both of them are going up and down with the cam, weve gone through everything, and we checked already to make sure the piston is going up and down and it is also,
 
i pulled the rocker covers and both of them are going up and down with the cam, weve gone through everything, and we checked already to make sure the piston is going up and down and it is also,

Did you try readjusting the rockers on the cylinder with a problem ? Is it possible a longer than stock pushrod could have been used ?

Before pulling the head...remove the rockers and do a leak down test.

David
 
if it dosent build compression to begin with. You wont find anything from the leak down test. A leak down test checks rings mostly because you time how long it takes the pressure to drop. A open valve wont build pressure period
 
if it dosent build compression to begin with. You wont find anything from the leak down test. A leak down test checks rings mostly because you time how long it takes the pressure to drop. A open valve wont build pressure period

I know what a leak down test is for. Your making an assumption that it's an open valve (probably correct)...applying air pressure to the cylinder with rockers removed (closes valves) will show you if the air is going into the pan (rings/piston) or into the intake manifold (valves/head).

David
 
im going to try that on monday, since i work 12 hours tommorow, thanks dudes, keep ya posted, im seriously fed up with the SC already, its just depressing staring at them...
 
I know what a leak down test is for. Your making an assumption that it's an open valve (probably correct)...applying air pressure to the cylinder with rockers removed (closes valves) will show you if the air is going into the pan (rings/piston) or into the intake manifold (valves/head).

David

99 times out of 100 it will be in the heads, because right now hes got compression on 5 other cylinders and one with nothing going on. Even if the piston ring was broke some form of compression would happen which is why im going with a valve problem they are prolly out of adjustment check the lash on each valve i dont recall the spec
 
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I had this happen on my first sc engine it was a lifter that was fully pumped up would not bleed out i replaced all the lifters but my buddy installed the rockers for me as i had to make a restroom run .

anyway he didnt notice the lifter was fully pumped up I undid the rockers some and it made compression so it was easy to find out which one then I had to remove the lifter for some reson it would not go down we even drained it cleaned it still it was stuck in fully expanded stuation.

I returned it got a new one and it worked fine . not saying this is definitly it but on mine it was a lifter.
 
99 times out of 100 it will be in the heads, because right now hes got compression on 5 other cylinders and one with nothing going on. Even if the piston ring was broke some form of compression would happen which is why im going with a valve problem they are prolly out of adjustment check the lash on each valve i dont recall the spec

Agreed-if he is indeed reading 0 pressure in only one cylinder, something is going on up top. Even if they didn't put piston rings on that one cylinder, it would still read at least a little bit of pressure.
 
Even though it is a hydro lifter, check valve lash. It only takes a second, and will tell you if you crushed a lifter, bent a pushrod etc ... after everything was put together.
 
Even though it is a hydro lifter, check valve lash. It only takes a second, and will tell you if you crushed a lifter, bent a pushrod etc ... after everything was put together.

Captain obvious to the rescue!!! Jason is actually trying to help someone, too bad your suggestion has already been MENTIONED several times. $99 says Manny is right. Checking lash won't tell you if you have a stuck lifter. :p
 
lol, dudes, i fixed it, i had to shim the rockers, most likely the ~~~~~~~s at the machine shop must have put valves a little too long on that side, so my dad put shims on the rockers, i will take pics, i havent seen it yet, too tired..
 
Agreed-if he is indeed reading 0 pressure in only one cylinder, something is going on up top. Even if they didn't put piston rings on that one cylinder, it would still read at least a little bit of pressure.

what if the machine shop just forgot a piston and rod all together :eek: lol...can you imagine? you take the head off, and you're staring at a totally empty cylinder like "ummmm...." haha i have no idea why i find this so funny
 
what if the machine shop just forgot a piston and rod all together :eek: lol...can you imagine? you take the head off, and you're staring at a totally empty cylinder like "ummmm...." haha i have no idea why i find this so funny

Huh. I suppose I never considered that. That would make a great internet picture though.
 
go ahead and check pushrod lenght....

Chances are though that they milled your head to much. Yah the shims will compensate but I'd check the pushrods..Also generally if you mill something that much yad have manifold seating issues.
 
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