No compression after cylinder head service
erndogy
11-04-2009, 03:27 AM
Hi all,
Well I just had a cylinder head serviced and installed it into my daughters '98 neon. It started up but idles really bad. I traced it the #1 cylinder. I got spark, I got fuel but when I pulled the spark plug cable and noticed not difference. Checked compression and I have none whatsoever. I put a little oil in to check piston rings and still no compression.
So my question is how can I check the valves without removing the cylinder head again? It is a single overhead cam. I have the haynes book but I don't think it is not much help in showing me how to check the valves.
Does anyone know how I can go about checking them or know where I can find info on-line?
Thanks
Erndogy
Well I just had a cylinder head serviced and installed it into my daughters '98 neon. It started up but idles really bad. I traced it the #1 cylinder. I got spark, I got fuel but when I pulled the spark plug cable and noticed not difference. Checked compression and I have none whatsoever. I put a little oil in to check piston rings and still no compression.
So my question is how can I check the valves without removing the cylinder head again? It is a single overhead cam. I have the haynes book but I don't think it is not much help in showing me how to check the valves.
Does anyone know how I can go about checking them or know where I can find info on-line?
Thanks
Erndogy
Airjer_
11-04-2009, 09:42 AM
If your compression gauge is a two piece than you can hook an air hose to it. Remove the schrader valve before you install it into the cylinder. Hook up the air hose limiting its pressure. Listen for rushing air in the exhaust or the intake. Wherever you hear it is the valve that is open. You need to make sure the #1 cylinder is TDC also
erndogy
11-06-2009, 07:27 PM
Thanks for the help. That would have helped me if I was able to get to a computer earlier.
I removed the valve cover and noticed the plastic piece that holds the lifter( lash adjusted) in place was all the way down on the spring. I spoke to the engine guy at the machine shop I use and he said " Oh dont worry about it. The lifter has not discharged yet and it is normal for them to get stuck after a major job. Just run the engine and once it stays on drive the car the car for a while."
I decided to take a closer look and noticed the plastic piece was broken and removed it. Thats when I noticed the lash adjuster was not sitting on the valve stem like it should and had moved out of place and was pressed between the rocker and the valve stem so the valve never fully closed.
I removed the rocker arm assy for the exhaust side and took it to the machine shop. They balked at having to replace the entire rocker arm assy because the individual lash adjusters are not replaceable.
I spoke with their cylinder head guy and he removed the tip and inspected it. Installed a new plastic piece and viola! the lash adjuster was as good as new. Installed last night and the engine started up right away with no further issues.
So I just finished up a while ago with and oil change, exhaust pipe gasket replacement, front motor mount replacement and rear light assy replacement.
The car is now ready for my daughter to go out and screw up again.:rofl:
Erndogy
I removed the valve cover and noticed the plastic piece that holds the lifter( lash adjusted) in place was all the way down on the spring. I spoke to the engine guy at the machine shop I use and he said " Oh dont worry about it. The lifter has not discharged yet and it is normal for them to get stuck after a major job. Just run the engine and once it stays on drive the car the car for a while."
I decided to take a closer look and noticed the plastic piece was broken and removed it. Thats when I noticed the lash adjuster was not sitting on the valve stem like it should and had moved out of place and was pressed between the rocker and the valve stem so the valve never fully closed.
I removed the rocker arm assy for the exhaust side and took it to the machine shop. They balked at having to replace the entire rocker arm assy because the individual lash adjusters are not replaceable.
I spoke with their cylinder head guy and he removed the tip and inspected it. Installed a new plastic piece and viola! the lash adjuster was as good as new. Installed last night and the engine started up right away with no further issues.
So I just finished up a while ago with and oil change, exhaust pipe gasket replacement, front motor mount replacement and rear light assy replacement.
The car is now ready for my daughter to go out and screw up again.:rofl:
Erndogy
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