Valve job now no start
#11
07-14-2012, 07:57 AM
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Location: Forked River N.J.
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All suggestions are welcome! If you are ever wrong about a suggestion, you will learn something when you are corrected.
Your correct about cam rotation being half of the crank. The crank turns twice each cycle while the cam turns once. Every 180 crank rotation, leaves 2 pistons up. 1&4 and 2&3. The cam position determines which stroke it's on. one will be on compression while the other will be between exhaust and intake stroke. The crank doesn't know the difference. In fact, some engines will fire spark when ever the piston is up, one fires while the other just sparks.
You should see how Harleys work. It's amazing that the even stay running. 2 cylinders on the same stroke at the same time. They fire both cylinders then nothing the next revolution. In a sense, they stall every other rotation! Wacky...Thank god for big flywheels.
Your correct about cam rotation being half of the crank. The crank turns twice each cycle while the cam turns once. Every 180 crank rotation, leaves 2 pistons up. 1&4 and 2&3. The cam position determines which stroke it's on. one will be on compression while the other will be between exhaust and intake stroke. The crank doesn't know the difference. In fact, some engines will fire spark when ever the piston is up, one fires while the other just sparks.
You should see how Harleys work. It's amazing that the even stay running. 2 cylinders on the same stroke at the same time. They fire both cylinders then nothing the next revolution. In a sense, they stall every other rotation! Wacky...Thank god for big flywheels.
#13
07-17-2012, 09:16 PM
so every turn the side thingy 360 degrees to the T mark... the piston in Cylinder #1 is up all the way. ...when i keep on turning the side thingy clockwise... eventually, it gets stuck... and i have to turn it counter-clockwise... is this normal?
this is what everything is like...
___ intake cam , ex cam ___ (on T)
turn it 360s.
the marks on intake and ex cams.. no longer straight like above.
turn side thing 360 again..
___ intake, ex ____ straight again
i assume this is right... the only thing i can do now is test for compression. the kit i haven't doesn't have the adapter for the f4i.. i'll have to go sears to see if I can find one.
this is what everything is like...
___ intake cam , ex cam ___ (on T)
turn it 360s.
the marks on intake and ex cams.. no longer straight like above.
turn side thing 360 again..
___ intake, ex ____ straight again
i assume this is right... the only thing i can do now is test for compression. the kit i haven't doesn't have the adapter for the f4i.. i'll have to go sears to see if I can find one.
#14
07-26-2012, 04:49 PM
#15
07-26-2012, 05:16 PM
When 1 is up, so will 4. 2 and 3 will be down.
What do you mean it locks up when you turn it? That points to binding on something. If the cams are off time and the motor was cranked over, the valves could have been bent. That would explain why you feel it stop when you turn it by hand and there is no compression. Measure the valve clearance. If the lash has become large, they're bent.
What do you mean it locks up when you turn it? That points to binding on something. If the cams are off time and the motor was cranked over, the valves could have been bent. That would explain why you feel it stop when you turn it by hand and there is no compression. Measure the valve clearance. If the lash has become large, they're bent.
#16
07-26-2012, 10:19 PM
i double checked the clearance before putting the valve cover back on, but I can do it again. i have a awful feeling that I need to pull off the head and look at stuff. grr. Before that, can someone confirm the following:
1. when the side is turned to the T marker. piston 1 is all the way at the top. and the markers (IN and EX) on the cams are as shown by the picture:
2. cylinder 1 is the cylinder farthest on the side of the clutch lever. It's the left most cylinder when you sit on the bike.
1. when the side is turned to the T marker. piston 1 is all the way at the top. and the markers (IN and EX) on the cams are as shown by the picture:
2. cylinder 1 is the cylinder farthest on the side of the clutch lever. It's the left most cylinder when you sit on the bike.
#19
08-08-2012, 05:13 PM
It comes down to either, I do not know how to perform a compression test on a motorcycle or that the valves are bent... or something of the sort.
I've pulled the head cylinder off. Aside from some dirty build up on carbon on the piston and valve surface, everything seems to be in order. I do not have the skills or tools to proceed and pull the valves. i'll probably take the head to a bike shop or something to have them check it out.
I've pulled the head cylinder off. Aside from some dirty build up on carbon on the piston and valve surface, everything seems to be in order. I do not have the skills or tools to proceed and pull the valves. i'll probably take the head to a bike shop or something to have them check it out.
#20
08-08-2012, 05:25 PM
Turn the head upside down (with the cams out). If the shims are still in the head, take them out and put them in order so the dont fall out.
Fill the chambers with water. If a valve is bent, it will leak past the seat and into the ports. You may be able to see a shinny part on the valve and/or piston where it made contact, if it did.
Just a note: before you put the head on, bolt the cams on and adjust the valves on the bench. take them back out and keep them in order. Then you wont need to mess with it in the bike.
Fill the chambers with water. If a valve is bent, it will leak past the seat and into the ports. You may be able to see a shinny part on the valve and/or piston where it made contact, if it did.
Just a note: before you put the head on, bolt the cams on and adjust the valves on the bench. take them back out and keep them in order. Then you wont need to mess with it in the bike.