tdc method...valve position
tdc method...valve position Hey guys, real quick...
Im trying to replace just two broken springs and i would like to do this using the tdc method.
however, i was wondering if this can be done while cranking the motor over with the key and not the crank bolt? I dont have a big enough wrench....
Also, since i dont have my timing cover off, i wanted to know where or how can i verify tdc with the position of the valves. BAsically, at tdc, will both valves be down or up?
thanks, i appreciate this..would like to get this done as soon as possible....
Im trying to replace just two broken springs and i would like to do this using the tdc method.
however, i was wondering if this can be done while cranking the motor over with the key and not the crank bolt? I dont have a big enough wrench....
Also, since i dont have my timing cover off, i wanted to know where or how can i verify tdc with the position of the valves. BAsically, at tdc, will both valves be down or up?
thanks, i appreciate this..would like to get this done as soon as possible....
so, basically i turn until both rockers are on the up position....
At this point, could i compress the spring so i can push down on the valve lightly and see how far it wil go down?...I just dont want to have a valve fall...that would SO suck right now!!!!!
At this point, could i compress the spring so i can push down on the valve lightly and see how far it wil go down?...I just dont want to have a valve fall...that would SO suck right now!!!!!
Right, you can also (if you have a friend to bump the starter over, or a remote start switch) put your finger on the spark plug hole (after removing the plug) and feel for the air coming out
IIRC the piston @tdc will keep the valve from falling all the way in (not sure of that for an LS1)
You could use the rope trick, feed some rope into the cylinder thru the plug hole, and that will hold the valve up once the spring is off
ls1howto I believe has a post on how to change springs with the heads on
IIRC the piston @tdc will keep the valve from falling all the way in (not sure of that for an LS1)
You could use the rope trick, feed some rope into the cylinder thru the plug hole, and that will hold the valve up once the spring is off
ls1howto I believe has a post on how to change springs with the heads on
The best way to do it is to remove the spark plug or plugs where the broken springs are located. Stick a plastic soda straw in the spark plug hole. Preferably some can turn the crank bolt and you will feel the piston coming up, if you go past tdc just turn the bolt in the opposite direction. This method is fool proof, I've been doing it for 45 years.
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im gonna try the this out now, i'm gonna have to try it using the starter since i dont have a wrench big enough for the crank bolt.....
thanks guys.
update, good or bad, soon to be posted....
thanks guys.
update, good or bad, soon to be posted....
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TECH Fanatic
Joined: Jan 2003
Posts: 1,094
Likes: 0
From: Northern Va
I agree, rope, straw, small hose... these are very good methods. I used a small diameter rubber hose. When the piston reaches the top of the cylinder it clamps down on the hose until it feels tight when you tug on it. Low-tech and pretty fail-safe.
well............
I got the plug of and used a straw to feel when in tdc. I cranked the motor over with the starter and with small cranks....it worked perfectly!!! ....
However....and im gonna try this without swearing my life away.....
I got the old, broken spring compressed with a compressor from an auto parts. Its the one with the handle. Locks like a crow-bar with a wedge/split end where the retainer goes.
Anyways, i got the spring compressed and removed the old spring and assembly. (sigh!) ....I installed the new spring assembly and when i was compressing to install the locks......
BLAM!!!!!!!!!!!!!!!!!!!!! The Fu...uh, freaking bolt broke off in the head!!!!!!!!!!!!!!!!!!!!!!!!!!! I used the yella terra bolt and that is gone!!!
AAAAAAAARRRRRRGGGGGGHHHHHHHHHHHH!!!!!!!!!!!!!!!!!! !!
Oh, did read that these are "notorious" for doing this but i figured that if i went slow that it would be ok....i didnt even crank it far enough to get the locks on....
DUDE!!! I flared!!!!!!!!!!!
Well, I guess my only solution right is to get the heads of and see if i can salvage them. If not, well, i guess this is a good time to inverst in a set of the new ET heads.
Im ao pisst'd.........my recomendation......NEVER USE THIS KIND OF SPRING COMPRESSOR!!!!!!!!!!!!!!!!!!!!!! EVER!!!!
.....OH, and thanks for the assistance, it helped alot just things like this just happened i guess....now to party as hard as i can so i can try and forget about this.
thanks again ppl!!
I got the plug of and used a straw to feel when in tdc. I cranked the motor over with the starter and with small cranks....it worked perfectly!!! ....
However....and im gonna try this without swearing my life away.....
I got the old, broken spring compressed with a compressor from an auto parts. Its the one with the handle. Locks like a crow-bar with a wedge/split end where the retainer goes.
Anyways, i got the spring compressed and removed the old spring and assembly. (sigh!) ....I installed the new spring assembly and when i was compressing to install the locks......
BLAM!!!!!!!!!!!!!!!!!!!!! The Fu...uh, freaking bolt broke off in the head!!!!!!!!!!!!!!!!!!!!!!!!!!! I used the yella terra bolt and that is gone!!!
AAAAAAAARRRRRRGGGGGGHHHHHHHHHHHH!!!!!!!!!!!!!!!!!! !!
Oh, did read that these are "notorious" for doing this but i figured that if i went slow that it would be ok....i didnt even crank it far enough to get the locks on....
DUDE!!! I flared!!!!!!!!!!!
Well, I guess my only solution right is to get the heads of and see if i can salvage them. If not, well, i guess this is a good time to inverst in a set of the new ET heads.
Im ao pisst'd.........my recomendation......NEVER USE THIS KIND OF SPRING COMPRESSOR!!!!!!!!!!!!!!!!!!!!!! EVER!!!!
.....OH, and thanks for the assistance, it helped alot just things like this just happened i guess....now to party as hard as i can so i can try and forget about this.
thanks again ppl!!
Originally Posted by MadBill
"Stage 3 Trans" in your sig sounds like an auto, but If it's a manual, you can also put it in gear and 'bump' the car forward or back to get it right at TDC...
TECH Fanatic
Joined: Jan 2003
Posts: 1,094
Likes: 0
From: Northern Va
Sorry to hear that man. After much research, I invested in the Crane spring removal tool and I have used it on 4 different spring removal jobs (it's slowly paying for itself). I know you probably don't want to hear this now but it's never a good idea to cheap out with the tools. Good luck with the head.
