PDA

View Full Version : LS-vtec, GSR head, small issue. i'm a newb to vtec.



teh_mugen18
09-20-2009, 10:00 AM
Okay, heres my issue.
I bought a vtec head from someone on a different website, and it didnt come with cams, or a solenoid or any of that. I had to source the parts myself, which i did. But, basically after finding the set of oem cams for the head and installing them with assembly lube on all the journals and rockers, it seems that when you try to turn the intake camshaft its exceptionally difficult to spin. The exhaust one seems to be okay. I checked all the LMA's for any binding, and there is none.

Now, i know that on the non-vtec heads, the cams are so easy that they can be spun by hand almost because the valve springs are so soft. Is it just in the nature of the vtec head that the camshafts can't really be spun by hand because the valve springs are harder, or is it possibly something else that could be wrong with the head? The only thing that worries me is the intake cam, because i'd hate to have it all installed and ready to run and then when we go to hand-turn the engine, the belt slips off and jumps timing because the cam gears are so hard to turn.:no: Can anyone offer some suggestions/advice? This is also my first bit of exposure to vtec parts, so im still learning bit by bit too. It might just be me being overly careful..

ls-r teg
09-20-2009, 10:18 AM
there both suppose to be hard 2 turn? but ona gsr head 1 side has dual valve springs i no that much. 2 lazy to research tho lol

masonhenson
09-20-2009, 10:18 AM
someone help this man

Slomaro Z28
09-20-2009, 10:57 AM
Intake side is where the secondaries are I believe.

http://suspendedhatch.thecarthing.com/gassavers/VTEC-E_diagram.gif

Might be why its harder to turn, just a thought don't take my word on it.

Barefoot
09-20-2009, 12:31 PM
i can turn both sides by hand. do u have any bent valve

Starrfire
09-20-2009, 12:40 PM
the picture above doesn't have anything to do with vtec when it isn't engaged, plus his is a single cam. Do you have the timing right? You may be trying to open the valves into the piston. Either that or a bent valve.

Slomaro Z28
09-20-2009, 12:45 PM
the picture above doesn't have anything to do with vtec when it isn't engaged, plus his is a single cam. Do you have the timing right? You may be trying to open the valves into the piston. Either that or a bent valve.

Really? A LS/Vtec single cam:thinking:

Edit: I see that the pic is a single cam now, and you missed the T in this

Maybe this, have you tried putting the timing belt on and turning over the motor by hand @ the crank?

masonhenson
09-20-2009, 12:45 PM
def a dohc...

teh_mugen18
09-20-2009, 01:15 PM
Well, the head isnt on the engine yet. I've been trying to weed out any issues with the head (if there are any left) before i install it to the block. I dont believe that there are any bent valves, but i didnt take it apart enough to see whether or not there were. I sent it out to the machine shop to have them put new valve stem seals in it. I would've thought they would let me know if there were any bent valves while they had it open. Since i didnt hear anything from them about it, i assume not. I guess i could take it apart and check for myself if there are any bent?

Also, i can turn both of them. Its just hard to do, and i have to turn it with a wrench.

EDIT: i just did a leakdown test on the valves by pouring water into all the intake/exhaust ports to see if they'd leak and none of the valves are leaking. They're all seated 100% properly, so i doubt the valves are bent. Still doesnt explain why my cams are so hard to turn though.

Barefoot
09-20-2009, 02:36 PM
are you tq the caps down to the right spec.

teh_mugen18
09-20-2009, 03:29 PM
are you tq the caps down to the right spec.

its 20 ft. lbs all around, right?

Barefoot
09-20-2009, 04:27 PM
its 20 ft. lbs all around, right?
yah everything but the small ones at the ends. is it jsut a lil tough to turn by hand or does it feel like its locked.

Starrfire
09-20-2009, 04:34 PM
Yeah I know both of the motors he is talking about is dohc. But you won't be able to turn them by hand anyways. So you would need a wrench. unless you got gorilla hands

Barefoot
09-20-2009, 04:38 PM
unless you got gorilla handsi normally can turn it by hand without a problem. i think im just used to. i do use a wrench if i just need it to turn 1 or 2 teeth. in his case im starting to believe everything is just fine. he is just over thinking what could go wrong.

teh_mugen18
09-20-2009, 04:47 PM
yah everything but the small ones at the ends. is it jsut a lil tough to turn by hand or does it feel like its locked.

Its very tough to turn, but it does definately turn and once i get it turning, the valves and stuff all open and close, etc. I have to turn it with a wrench, and when i start turning it, i kinda hafta stand on the head or put a little bit of extra weight on it to make sure that the whole thing wont move when i start trying to move the cams. Does that sound about right? (lol keep in mind, the head isnt bolted to anything yet)

I think that i might be over-thinking it too, but you can't be too careful when you're trying to do major upgrades to a daily driver lol ;)

Starrfire
09-20-2009, 05:51 PM
I've never tried to spin my valvetrain over by hand, I can the crank very easily because I know it's supposed to, but there really isn't any ergonomic places to grip it if you know what I mean.

teh_mugen18
09-20-2009, 06:17 PM
I've never tried to spin my valvetrain over by hand, I can the crank very easily because I know it's supposed to, but there really isn't any ergonomic places to grip it if you know what I mean.


Yeah, i know what you mean.. also, theres the fact that the belt tensioner does the job of making the belt as tight as it can to the sprockets and the way the pulley system is designed on these engines is supposed to "multiply" the strength of the belt, like how the crank turns 180degrees and each of the camgears only turn 90degrees, so im hoping that when i get this all together that itll be easier to turn when i do it from the crank. Not to mention, that there's no oil in the head other than the assembly lube, so thats probably also adding a lot of extra friction to the equation too.

I'm gonna be so glad when this is all over with :blah::blah: