Engine Rotation Locking
- Buffalo515
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Engine Rotation Locking
Today 13:22
Been rebuilding this 1985 zx550A. The entire engine has been taken apart and put back together. When i try to rotate the engine with the cams in it stops at 2 places. Heres some troubleshooting ive done so far.
-No bent valves. I pulled the head after this condition to make sure again after this.
-Timed the cams according to service manual and louds graphics.
-engine rotates freely with cams removed so i think bottom end is fine
-Checked valve clearances for each valve. All meet the minimum clearance so its not a lack of clearance.
-Ive removed the tensioner and still experience this condition while rotating with hand pressure keep the chain on the sprockets.
-Everything is oiled with a light coat of oil and the caps are torqued to spec in order of service manual
-It stops at the same two spots every time. (Intake 1 and Exhaust 2 depressed / Intake 3 and Exhaust 1 depressed).
Ive included pictures of my cam timing and of the positions of everything in these two spots. Let me know what you think im kindve lost.
-No bent valves. I pulled the head after this condition to make sure again after this.
-Timed the cams according to service manual and louds graphics.
-engine rotates freely with cams removed so i think bottom end is fine
-Checked valve clearances for each valve. All meet the minimum clearance so its not a lack of clearance.
-Ive removed the tensioner and still experience this condition while rotating with hand pressure keep the chain on the sprockets.
-Everything is oiled with a light coat of oil and the caps are torqued to spec in order of service manual
-It stops at the same two spots every time. (Intake 1 and Exhaust 2 depressed / Intake 3 and Exhaust 1 depressed).
Ive included pictures of my cam timing and of the positions of everything in these two spots. Let me know what you think im kindve lost.
Travis
Maryland
1981 GPZ 550 -gone
1984 GPZ 550
1985 GPZ 550
Maryland
1981 GPZ 550 -gone
1984 GPZ 550
1985 GPZ 550
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- StreetfighterKz
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Re: Engine Rotation Locking
Today 14:15
You show multiple “timing mark” pics as far as I can tell. The cam lobes for #1 are typically facing directly toward each other when 1&4 are at TDC. It’s really hard to tell from your pics is that’s the case.
Later, Doug
Later, Doug
1978 z1000 Streetfighter
1976 z900 ‘Stripfighter
1978 z1000 w/RC Turbo
1979 z650 Resto-Mod
1983 Gpz750 Resto-Mod
2018 Z900RS
1976 z900 ‘Stripfighter
1978 z1000 w/RC Turbo
1979 z650 Resto-Mod
1983 Gpz750 Resto-Mod
2018 Z900RS
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- StreetfighterKz
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Re: Engine Rotation Locking
Today 14:22
The lobes on #1 can also face away, as that would be the compression stroke as the exhaust lobe would be close to opening the valve.
Later, Doug
Later, Doug
1978 z1000 Streetfighter
1976 z900 ‘Stripfighter
1978 z1000 w/RC Turbo
1979 z650 Resto-Mod
1983 Gpz750 Resto-Mod
2018 Z900RS
1976 z900 ‘Stripfighter
1978 z1000 w/RC Turbo
1979 z650 Resto-Mod
1983 Gpz750 Resto-Mod
2018 Z900RS
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- Wookie58
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Re: Engine Rotation Locking
Today 15:25 - Today 15:34
As well as the timing marks have you confirmed correct pin count between the sprockets ?
you say it locks in two places, have you forced it past the first one to find there is a second?
rotating the motor while trying to tension the chain with your hand is a recipe for disaster. Reset the marks with the tensioner removed and the correct pin count, refit the cam cover, reset the tensioner then try to rotate the motor
you say it locks in two places, have you forced it past the first one to find there is a second?
rotating the motor while trying to tension the chain with your hand is a recipe for disaster. Reset the marks with the tensioner removed and the correct pin count, refit the cam cover, reset the tensioner then try to rotate the motor
1982 KZ1000 Ltd
www.kzrider.com/forum/11-projects/617631...-82-begins?start=192
kzrider.com/forum/faq-wiki/616810-electr...-fault-finding-guide
www.kzrider.com/forum/11-projects/617631...-82-begins?start=192
kzrider.com/forum/faq-wiki/616810-electr...-fault-finding-guide
Last edit: Today 15:34 by Wookie58.
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