- Posts: 38
- Thank you received: 1
No compression in #2 Cylinder
- monroeraustin
- Topic Author
- Offline
- User
Please Log in or Create an account to join the conversation.
- wireman
- Offline
- User
- The most interesting prick in the world
- Posts: 4761
- Thank you received: 299
Sounds like low compression on all 4 to me,did you hold throttle wide open when you ran the compression test?
Id try dumping a little oil down the cylinders and check numbers again.
posting from deep under a non-descript barn in an undisclosed location southwest of Omaha.
Please Log in or Create an account to join the conversation.
- monroeraustin
- Topic Author
- Offline
- User
- Posts: 38
- Thank you received: 1
Please Log in or Create an account to join the conversation.
- monroeraustin
- Topic Author
- Offline
- User
- Posts: 38
- Thank you received: 1
Please Log in or Create an account to join the conversation.
- wireman
- Offline
- User
- The most interesting prick in the world
- Posts: 4761
- Thank you received: 299
Leaking valves would cause same issue,if the compression goes up after dumping more oil down the cylinders and retesting id say rings,if it doesnt id look at a valve job
posting from deep under a non-descript barn in an undisclosed location southwest of Omaha.
Please Log in or Create an account to join the conversation.
- monroeraustin
- Topic Author
- Offline
- User
- Posts: 38
- Thank you received: 1
Attachment ring.jpg not found
Please Log in or Create an account to join the conversation.
- baldy110
- Offline
- User
- Posts: 2272
- Thank you received: 512
Please Log in or Create an account to join the conversation.
- monroeraustin
- Topic Author
- Offline
- User
- Posts: 38
- Thank you received: 1
Attachment 101.JPG not found
Attachment 102.JPG not found
Attachment 103.JPG not found
Attachment 104.JPG not found
Attachment timingmarks.jpg not found
Please Log in or Create an account to join the conversation.
- Patton
- Offline
- KZr Legend
- Posts: 18640
- Thank you received: 2098
Should have specific directions and pictures.
Click the link and scroll down to "The Bible."
kz.bike-night.com/
Good Fortune!
1973 Z1
KZ900 LTD
Please Log in or Create an account to join the conversation.
- OldSchoolZ
- Offline
- User
- Posts: 217
- Thank you received: 33
Remember, don't work on your bike so much you never ride it.
Please Log in or Create an account to join the conversation.
- monroeraustin
- Topic Author
- Offline
- User
- Posts: 38
- Thank you received: 1
OldSchoolZ wrote: Im suspecting a valve problem, possibly bent valve maybe more than one. If cam timing is off, usually comp is different on all cylinders. Always fluid check your valves through the ports before installing.
Oldschooolz thanks i appreciate your comment. I'd like to entertain every possible scenario so to try to pinpoint where to start looking next. I just installed new valve boots, cleaned and checked the valves and they are not bent. I have provided photos of the timing marks and have followed the provided instructions by turning the crank to "T" TOP DEAD CENTER for 1-4. I have also checked by looking thru the #1 and 4 spark plug whole to make sure I see the piston at the top. I've lined up the marks. I am not getting good compression in every cylinder and in one I am getting no pressure at all. Rings are new and the cylinder has been honed. Hypothetically, If timing is correct, and valves aren't bent what do I look at next? I've heard so far check the timing, and or valves is there anything else which might cause this problem. I will be tearing the engine back down I just need some idea direction to go in next. Thanks..
Please Log in or Create an account to join the conversation.
- Patton
- Offline
- KZr Legend
- Posts: 18640
- Thank you received: 2098
Can perform a poor man's leak down test by introducing compressed air into a spark plug hole and listening to where it escapes from the combustion clamber. This may be done at TDC or any other cam positions where both valves are fully closed. Top dead center (TDC) is when the piston is at its highest position. An easy way to tell TDC is by alignment of the T mark with the case mark when viewed through the timing window.
May introduce a spurt of compressed air by using a rubber cone-tip blow gun (rubber air nozzle) held into the spark plug hole. And of course keep holding it in position to keep air from coming back out the spark plug hole while listening for escaping air at other places. The air compressor should not be running while listening because the noise will likely drown out any sound of escaping air.
Air heard escaping from exhaust port indicates exhaust valve not fully closing (perhaps too tight clearance or damaged valve or valve seat).
Air heard escaping from carb intake indicates intake valve not fully closing (perhaps too tight clearance or damaged valve or valve seat).
Air heard escaping from crankcase breather indicates loss of compression past rings into crankcase (perhaps worn piston rings or cylinders).
Air heard escaping from head gasket area indicates indicates loss of compression past head gasket (perhaps due to a blown head gasket).
A leaking valve may sometimes be resolved by adjusting the clearance to within specs.
A leaking head gasket may sometimes be resolved by torquing the head fasteners when the engine is stone cold (such as after sitting overnight).
Good Fortune!
1973 Z1
KZ900 LTD
Please Log in or Create an account to join the conversation.