Thanks
Announcement
Collapse
No announcement yet.
Did I just crash a valve?
Collapse
X
-
Did I just crash a valve?
In the middle of checking valve clearances and moving shims I jumped from no 1 exhaust (I think) to #3 exhaust without moving the engine. The cam lobe was pointing at the front of the bike (on #3). I didn't feel any difference and to be truthful didn't think about it. Don't know why but I woke up this morning thinking what a dummy I was. Then a buddy says it doesn't matter. Sorry for the long explanation but want to know if the cam lobe is pointing straight up or at 90 degrees to the outside of the engine(depending on int or ex.) am I OK or do I need to compression test this thing???
ThanksTags: None
-
I can't see how you could possibly have crashed a valve without moving the engine. Even then you would have to have disconnected the cams from the crank. Am I right in thinking that what you did was just checked clearances in the wrong sequence and did #1 and #3 together instead of #1 and #2 ?
Oh yeah, what bike ?97 R1100R
Previous
80 GS850G, 79 Z400B, 85 R100RT, 80 Z650D, 76 CB200
-
Jamesp
Its a GS 1100. I just thought if the piston happened to be TDC I could have pushed the valve into it. I was actually depressing the bucket to put a different shim in because the shim from one was what I needed in 3
Comment
-
koolaid_kid
Comment
-
Jamesp
Sorry 1100 GLZ. Didn't realize there were motors in that era that didn't use shims. Of course you couldn't fill a thimble with what I know about bikes--just willing to learn.
Comment
-
If you had pushed a valve into a piston with a hand tool you would have felt it. Normal procedure after refitting timing chains or belts is to turn the motor over by hand to see if a valve touches. This is a standard safety check and you know you screwed up if the motor won't turn as in locks up solid. It doesn't kill the valves or pistons.
Valves are pretty tough customers. I don't think Arnie on steroids could bend a valve with a bucket tool.97 R1100R
Previous
80 GS850G, 79 Z400B, 85 R100RT, 80 Z650D, 76 CB200
Comment
-
Jamesp
-
Originally posted by 850 Combat View PostThe manual shows checking the valves with the lobe parallel with the gasket surface pointed away from the valve stem, , OR pointed straight up.
The reason for that is that both lobes are pointing somewhat away from the valves. They are at least far enough away that neither one of them is pushing on a valve, which ensures that the cam is centered in the bearing on that side of the engine. That will give more-consistent and accurate readings.
If you start with EX 1&2, you can check both valves, turn the crank 180 degrees (1/2 turn), check IN 1&2, turn the crank another 180 degrees, check EX 3&4, turn the crank a final 180 degrees, check IN 3&4.
Once you see the logic and the pattern, it's quite simple, but many first-timers struggle to get the cam lobes in the correct position for each valve, when you are supposed to do them in pairs.
.sigpic
mine: 2000 Honda GoldWing GL1500SE and 1980 GS850G'K' "Junior"
hers: 1982 GS850GL - "Angel" and 1969 Suzuki T250 Scrambler
#1 son: 1986 Yamaha Venture Royale 1300 and 1982 GS650GL "Rat Bagger"
#2 son: 1980 GS1000G
Family Portrait
Siblings and Spouses
Mom's first ride
Want a copy of my valve adjust spreadsheet for your 2-valve per cylinder engine? Send me an e-mail request (not a PM)
(Click on my username in the upper-left corner for e-mail info.)
Comment
-
Jamesp
I did check them in pairs but when i was shifting the shims around I got into a hurry and when I saw the lobe in the right position I just put in the shim in not realizing that the engine (for measuring) needed a 180. When I did realize it, I thought maybe there was more than just cam position that mattered (3 being TDC and running into the piston)and got real worried!!! Still wierd I woke up thinking about it. Thanks for all your imput!!!
The dog got hit by a car tonight so I still didn't get any sleep--and I thought the bike was expensive!!! For those who care, he came out with a couple casts-- he'll be fine.
Comment
Comment