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pistons not at TDC as marked at crankshaft?
- BretY
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But my question has to do with this: I have the crankshaft T mark (the T next to the F1.4 as in the clymer book) lined up with the indicator mark as illustrated in posts here and in the book, but 1 and 4 pistons are definitely not at the top of their stroke, nor are 2-3 either. 1 and 4 are at the top at about a 1/4 turn of the shaft prior to T lining up with the mark. I am assuming that 1 and 4 should be at the top when the T is lined up with the mark? - The head is off now so I can clearly see where the pistons are. And I sure don't want to attempt to put a head back on until I know I will have the engine where it should be to reinstall the cams...
Could anyone tell me what would throw this off? I don't want to proceed with anything else until I know what I am dealing with.
Thanks!
Brett
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- loudhvx
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I believe the 750 is a one-piece crank like the 650 and 550, so I don't think there is a twist issue that you occasionally find on the big motors.
Another possibility is that the timing rotor was replaced at some point with one from another model. If your bike is a Zx750, then it came with electronic-advance. The rotor will be a one-piece rotor and might have the number 1069 stamped on it somewhere. It's possible to retrofit an older ignition onto the motor, even from a different model size. A 550 advancer should fit and most/all advancers from Kz650's and Kz750's would fit. This could lead to the timing marks being in the wrong positions. If you can post photos of the ignition rotor and pickup area, maybe someone can identify if you have the correct one.
1981 KZ550 D1 gpz.
Kz550 valve train warning.
Other links.
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- Scirocco
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You have to pull the cylinder for a closer look for more damages.
My 1975 Z 1 B 900 Project
www.kzrider.com/forum/11-projects/605133...ears-deep-sleep-mode
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- loudhvx
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1981 KZ550 D1 gpz.
Kz550 valve train warning.
Other links.
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- Scirocco
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Some pics of the damaged engine parts are very helpfull
My 1975 Z 1 B 900 Project
www.kzrider.com/forum/11-projects/605133...ears-deep-sleep-mode
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- Irish Yobbo
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I would inspect the ignition rotor before pulling the block.
1981 KZ750 LTD
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- Nessism
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Irish Yobbo wrote: The fact that the 1 and 4 pistons are both off the mark makes it unlikely to be a rod. If only one of them was off the mark that would make sense, but for both to be off that would mean two rods bent by the same amount.
I would inspect the ignition rotor before pulling the block.
Any time the head is removed the cylinder block should be too or the probability is high that a base gasket leak may occur.
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- BretY
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Thanks again!
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- loudhvx
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The larger nut-shape is what you use to turn the crank or hold the crank.
You hold the nut with a big wrench while turning the bolt. The bolt is just a normal bolt.
Here's the rotor you should be looking at.
1981 KZ550 D1 gpz.
Kz550 valve train warning.
Other links.
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- BretY
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I've notice it is hard to find a used head for one of these. But there are a few bikes around craigslist that are beat up but "running" while mine looks great, but is not running.... Maybe it would be smarter to swap out the whole engine?
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- loudhvx
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Maybe someone here can chime in on the possibility of welding up the gouges and re-grinding the dome in the head.
But I suppose if you were going to do all that, you could use a standard Kz head and up the compression on that. That way you won't have to worry about a hidden crack somewhere.
I forget if the Zx550 motor had higher compression than the standard Kz. In the 550 world, the Gpz's had 10:1 where all the other Kz550's had 9.5:1.
1981 KZ550 D1 gpz.
Kz550 valve train warning.
Other links.
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- old_kaw
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loudhvx wrote: That is some pretty bad looking damage.
Hold my coffee.
A XS1100 yamaha I bought for parts. The valve head broke off somewhere out of state, and they kept riding it home. Beats walking:
There wasn't much to lose at this point. Beats walking:
1981 Kawasaki Kz1000K1
Located in the Saint Louis, Missouri Area.
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