Valves, not seating?
Mikelb
06-04-2007, 01:04 PM
I pulled the head on the Talon Sat.
Everything went smoothly...
All the timing marks were aligned before I took the heads off (no interferance). The car ran out fine before the heads were removed (even fixed the damn idle [gaskets;)]).
I took the heads and laid them on my porch, aligned the marks, and looked closely. Something just wasn't right. I have 4 valves (intake, cylinders 2&3) that aren't seating. They stick out enough that there has to be some leaking. I'm not really familiar with the internals of engines (as far as putting one together, I know what everything does, just no hands-on internal work).
Is there a way to adjust these valves? Do I need to pull them and make sure they aren't bent (none of the others are?!?)?
I'll see if I can get some pics.
P.S.-I didn't realize that the car had a MLS...
Everything went smoothly...
All the timing marks were aligned before I took the heads off (no interferance). The car ran out fine before the heads were removed (even fixed the damn idle [gaskets;)]).
I took the heads and laid them on my porch, aligned the marks, and looked closely. Something just wasn't right. I have 4 valves (intake, cylinders 2&3) that aren't seating. They stick out enough that there has to be some leaking. I'm not really familiar with the internals of engines (as far as putting one together, I know what everything does, just no hands-on internal work).
Is there a way to adjust these valves? Do I need to pull them and make sure they aren't bent (none of the others are?!?)?
I'll see if I can get some pics.
P.S.-I didn't realize that the car had a MLS...
kjewer1
06-04-2007, 11:00 PM
First things first, there is only one head. :) Second, if the cams are installed, you will never have all of the valves closed at the same time. With the cams removed you can check the closing of each valve. But, if compression is good, the valves are closing fully. Even the slightest gap at the seat will result in zero reading during a compression test.
gthompson97
06-05-2007, 12:31 AM
Kevin is right about if there are cams in you will always have valves open and closed, but I'm assuming you pulled the cams before you took the head off, it seems much easier to get the head bolts out that way. Anyways, there's no way to adjust the valves on theses cars, they're hydraulic lifters so you'll need to be pulling those valves. I'll put $1 down that you'll be joining the "bending valves 101" club with Dustin and I.
Mikelb
06-05-2007, 08:33 AM
Ok, I have pulled the HEAD... sry for my mistake, I realize there is only one... I'm used to a V6.
I didn't pull the cams, but I can rotate them slightly and get the valves to close on cylinders 1 and 4, they didn't close on 2 and 3. I'll pull the cams, but isn't there some specific pattern for removing the bolts (I don't have $$$ or a manual right now).
It wasn't hard to remove the headbolts with the cams in place. That's what an extension and breaker bar (with added pipe ;)) are for. 20min tops. (yes, I used the correct torque procedure, in reverse).
I didn't pull the cams, but I can rotate them slightly and get the valves to close on cylinders 1 and 4, they didn't close on 2 and 3. I'll pull the cams, but isn't there some specific pattern for removing the bolts (I don't have $$$ or a manual right now).
It wasn't hard to remove the headbolts with the cams in place. That's what an extension and breaker bar (with added pipe ;)) are for. 20min tops. (yes, I used the correct torque procedure, in reverse).
smoke121212
06-05-2007, 08:56 AM
I'll put $1 down that you'll be joining the "bending valves 101" club with Dustin and I.
wow you can tell he gambles a lot.:grinno:
wow you can tell he gambles a lot.:grinno:
l_eclipse_l
06-05-2007, 06:41 PM
I learn more in one of Kevin's posts than I do in any 20 others I read.
kjewer1
06-05-2007, 08:46 PM
Thanks, but my POS is still slow, so take anything I say with a grain of salt. :D
There is no real specific order for take off the cam caps, but the typical outside in pattern wouldn't hurt. I do the opposite putting the caps back on. Keep in mind that the cap bolts only get about 18 ft-lbs since they go into aluminum.
If you only rotated the cams slightly as your post implies, all valves wouldn't close, you would have to do at least one complete rotation to get them all. If you rotated the cams and the valves didn't close when the followers were on the base circles that is not a good sign, but I would pull the cams to be sure. It's possible to have other problems, like pumped up lifters, etc.
For reference, with the head setup at TDC for #1, #1 would be in overlap and number 4 is in compression, so they should all be close to being closed and only a few degrees of movement would be required to close them all. Cylinders 2 and 3 would be in either intake/compression (BDC, intake valve will remain open until ~30 degrees ABDC) or power/exhaust (exhaust valve opens before BDC in the power stroke), so valves would be open on both of those cylinders.
There is no real specific order for take off the cam caps, but the typical outside in pattern wouldn't hurt. I do the opposite putting the caps back on. Keep in mind that the cap bolts only get about 18 ft-lbs since they go into aluminum.
If you only rotated the cams slightly as your post implies, all valves wouldn't close, you would have to do at least one complete rotation to get them all. If you rotated the cams and the valves didn't close when the followers were on the base circles that is not a good sign, but I would pull the cams to be sure. It's possible to have other problems, like pumped up lifters, etc.
For reference, with the head setup at TDC for #1, #1 would be in overlap and number 4 is in compression, so they should all be close to being closed and only a few degrees of movement would be required to close them all. Cylinders 2 and 3 would be in either intake/compression (BDC, intake valve will remain open until ~30 degrees ABDC) or power/exhaust (exhaust valve opens before BDC in the power stroke), so valves would be open on both of those cylinders.
Mikelb
06-06-2007, 09:02 AM
Thanks, but my POS is still slow, so take anything I say with a grain of salt. :D
There is no real specific order for take off the cam caps, but the typical outside in pattern wouldn't hurt. I do the opposite putting the caps back on. Keep in mind that the cap bolts only get about 18 ft-lbs since they go into aluminum.
If you only rotated the cams slightly as your post implies, all valves wouldn't close, you would have to do at least one complete rotation to get them all. If you rotated the cams and the valves didn't close when the followers were on the base circles that is not a good sign, but I would pull the cams to be sure. It's possible to have other problems, like pumped up lifters, etc.
For reference, with the head setup at TDC for #1, #1 would be in overlap and number 4 is in compression, so they should all be close to being closed and only a few degrees of movement would be required to close them all. Cylinders 2 and 3 would be in either intake/compression (BDC, intake valve will remain open until ~30 degrees ABDC) or power/exhaust (exhaust valve opens before BDC in the power stroke), so valves would be open on both of those cylinders.
You know that actually makes sense when I think about it... cylinders 1 and 4 (with the heads removed, cyl 1 at TDC) are closed, 2 and 3 are not. I didn't rotate the cams but a few degrees, b/c I didn't want to damage the journals(?). Cyl 2 and 3 have the int valves open, so it all makes sense. I'll remove the cams just to check the valves, but they're probably ok (I would assume, the car ran fine before it sat). I might check the lifters too.
Thanks
There is no real specific order for take off the cam caps, but the typical outside in pattern wouldn't hurt. I do the opposite putting the caps back on. Keep in mind that the cap bolts only get about 18 ft-lbs since they go into aluminum.
If you only rotated the cams slightly as your post implies, all valves wouldn't close, you would have to do at least one complete rotation to get them all. If you rotated the cams and the valves didn't close when the followers were on the base circles that is not a good sign, but I would pull the cams to be sure. It's possible to have other problems, like pumped up lifters, etc.
For reference, with the head setup at TDC for #1, #1 would be in overlap and number 4 is in compression, so they should all be close to being closed and only a few degrees of movement would be required to close them all. Cylinders 2 and 3 would be in either intake/compression (BDC, intake valve will remain open until ~30 degrees ABDC) or power/exhaust (exhaust valve opens before BDC in the power stroke), so valves would be open on both of those cylinders.
You know that actually makes sense when I think about it... cylinders 1 and 4 (with the heads removed, cyl 1 at TDC) are closed, 2 and 3 are not. I didn't rotate the cams but a few degrees, b/c I didn't want to damage the journals(?). Cyl 2 and 3 have the int valves open, so it all makes sense. I'll remove the cams just to check the valves, but they're probably ok (I would assume, the car ran fine before it sat). I might check the lifters too.
Thanks
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