Bent Valves???

[ChvyKc]

I am trying to figure out what is keeping my 1st gen from starting. I have gone through everything except for the head. I know that the bottom end is good. I pulled it straight out of a running car. One of my buddies and I pulled the head off the other day and the intake valves seems to be sitting up a little bit. They don't look like they have a gap, but I was just wondering if this was normal. I don't have a lot of experience with a 4G. It looks just like the edge of the vavle is a little big or something so it won't set flush with the head. Any help will be appreciated.

Thanks,

David

 

[gsx_tuner]

You should have done a compression test before you took the head off. You can however see if the valves are bent. If you keep moving the cam gears, at one point you should be able to get both sides closed. Keep moving them one at a time until they are shut on both sides. If you can get pretty close, and see that one vavle is bent, there you go.

 

[ChvyKc]

Yeah, we thought of the compression test after we took the head off (good job huh???) We had to swap the heads on the cars because the first one was cracked. We wanted to go back through what we did to make sure that we did everything right and when we got the head off we took the cams out to see how the valves were sitting and that is what I was asking about. The valves look like they are closed but they are just not sitting flush with the head. I just wanted to know if that was normal or not. I guess that I can always put the head back on and do a compression test, but really didn't want to go back through all of that. Any other help will be appreciated.

Thanks,

David

 

[Defiant]

Originally posted by ChvyKc
The valves look like they are closed but they are just not sitting flush with the head.

If you can't tell by looking, turn the head upside down and pour some kerosene into the combustion chamber. It shouldn't leak out.

Although I don't know what you mean by "flush with the head". Valves almost always stand up from the head a bit, depending on how the seats and faces were cut.

 

[ChvyKc]

I didn't think that the valves set flush with the head. I will try the kerosene thing out and see what happens. If it works out fine then I will put the head back on and if it doesn't start then I will do a compression test. Thanks for the help.

Thanks,

David

 

[gsx_tuner]

At one point, you should be able to turn the cam gears, and get each cam to get its valves flush in the SEATS on every cylinder. If this doesn't happen, you're screwed. Also, I hoped when you put the cams back on, you made sure you put each cap was in the exact order they were in when you took them off. This is crucial.

 

[92awddsm]

What kind of head gasket? Most head gaskets can only be used once...... After it is torqued, the fire rings around the cylinder compress and wont seal on a reinstall which = zero compression = no start. If vavles dont leak, Install head with NEW head gasket, make sure timing belt is on correctly, disconnect fuel pump, check compression on all cylinders, check to make sure all 4 plugs are firing, and if all is good, reconnect fuel pump(dont want engine to fill up with fuel while you check these things), and try to start. If it doesnt start, start checking fuel system and air filter. A healthy engine only needs 3 things to run. They are air, fuel and fire.

 

[ChvyKc]

I didn't know that these head gaskets couldn't be used again. I am not for sure what kind of head gasket it is, but I will be investing in one asap. Didn't even think about that. I have extensive knowledge and experience with Starions/Conquests but this is my first true DSM. The 4G63 seems to be a little more picky than the G54. I am still learning on these motors and I appreciate all of the help. Any more help will be appreciated. Oh, and any suggestions on head gaskets????

Thanks,

David

 

[92awddsm]

OE Mitsu head gasket. Im running a felpro but just got my car running fri after battling problems for a yearso I cant tell you if good or bad. We will see if it hols up to 20+ psi of boost

 

[ChvyKc]

That is what I was planning on going with. Hopefully that will hold up for the time being. I don't plan on a turbo upgrade until next fall so the felpro should be fine.

Thanks,

David