valve clearance check question


9 replies to this topic
  • atf8611

Posted October 23, 2005 - 08:15 AM

#1

before starting this project, i could not move the piston past tdc without using the decomp lever. when i took the valve cover off and went to line up everything at tdc by hand, i was able to cycle the piston through tdc without a whole lot of trouble. is this bad or is it normal? i havent put everything back together yet b/c i am waiting on some shims.

bike is a 99 wr400 btw

  • tshe1

Posted October 23, 2005 - 08:29 AM

#2

before starting this project, i could not move the piston past tdc without using the decomp lever. when i took the valve cover off and went to line up everything at tdc by hand, i was able to cycle the piston through tdc without a whole lot of trouble. is this bad or is it normal? i havent put everything back together yet b/c i am waiting on some shims.

bike is a 99 wr400 btw


i can think about 3 reasons:
1. the timing is wrong and you are not were you think you are (TDC).
2. most likely, did you removed or loosen the spark plug?
3. your decomp was stuck and pushing down the exhaust valve (open valve).
can you explain the steps you take??

  • atf8611

Posted October 23, 2005 - 08:37 AM

#3

i can think about 3 reasons:
1. the timing is wrong and you are not were you think you are (TDC).
2. most likely, did you removed or loosen the spark plug?
3. your decomp was stuck and pushing down the exhaust valve (open valve).
can you explain the steps you take??



1. i am at tdc b/c the cams, before i removed them, were facing outwards and the E and I marks on them were it the correct position and the I was lined up in the window thing correctly.

2. i didnt pull the plug yet, but i did remove the cap and that was sort of a struggle. it might have loosened it?

3. i dont think the decomp was stuck, but there is a chance it was.

im going to go check the plug right now. i have done everything so far following the instructions in the manual.

  • atf8611

Posted October 23, 2005 - 09:00 AM

#4

well the plug was fine. it was old, but it was in there fine.

  • tshe1

Posted October 23, 2005 - 09:03 AM

#5

1. i am at tdc b/c the cams, before i removed them, were facing outwards and the E and I marks on them were it the correct position and the I was lined up in the window thing correctly.

2. i didnt pull the plug yet, but i did remove the cap and that was sort of a struggle. it might have loosened it?

3. i dont think the decomp was stuck, but there is a chance it was.

im going to go check the plug right now. i have done everything so far following the instructions in the manual.


i will sugest for test:
1.pull the decomp lever out
2. remove the cams and make sure that the valves are closed (jently tap on the caps).
3. tighten the plug.
their should be compression if it wes their from the bigining.

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  • byggd

Posted October 23, 2005 - 09:39 AM

#6

before starting this project, i could not move the piston past tdc without using the decomp lever. when i took the valve cover off and went to line up everything at tdc by hand, i was able to cycle the piston through tdc without a whole lot of trouble. is this bad or is it normal? i havent put everything back together yet b/c i am waiting on some shims.

bike is a 99 wr400 btw

I'm confused by your question.
"before starting this project" so the plug was still in? That would explain why it wouldn't go past TDC.
"when i took the valve cover off" I'm assuming the plug is out now and the engine should turn over easily. :banghead:

  • atf8611

Posted October 23, 2005 - 09:41 AM

#7

i will sugest for test:
1.pull the decomp lever out
2. remove the cams and make sure that the valves are closed (jently tap on the caps).
3. tighten the plug.
their should be compression if it wes their from the bigining.



I think I will do that when I get a chance. 1 question before i do that, does the "I" marker come around only at tdc on the compression stroke, or does it come around at other times. I ask because i dont want to have a hard time putting everything back together.

  • tshe1

Posted October 23, 2005 - 10:51 AM

#8

I think I will do that when I get a chance. 1 question before i do that, does the "I" marker come around only at tdc on the compression stroke, or does it come around at other times. I ask because i dont want to have a hard time putting everything back together.


the "I" mark can come either when it is at top compression or at final expail.
align the "I" mark and notice that the letter "E" on both cams should be to the left , as described in the manual.

  • atf8611

Posted October 23, 2005 - 11:01 AM

#9

the "I" mark can come either when it is at top compression or at final expail.
align the "I" mark and notice that the letter "E" on both cams should be to the left , as described in the manual.



its lined up fine right now with the cams off, i was just wondering about it lineing up with the cams off and nothing to go by.

  • atf8611

Posted October 23, 2005 - 11:01 AM

#10

I'm confused by your question.
"before starting this project" so the plug was still in? That would explain why it wouldn't go past TDC.
"when i took the valve cover off" I'm assuming the plug is out now and the engine should turn over easily. :banghead:


i took the valve cover off with the plug still in place.




 
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