Identify my new engine rattle - 1981 KZ750 LTD

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Re: Identify my new engine rattle - 1981 KZ750 LTD

04 May 2017 02:22
#761134
So using my stethoscope, I've determined that it's definitely coming from the left-side cover, so most likely that either the stator or rotor has come loose.

So my next question is, that side cover has a gasket. Does that mean that it's holding in oil and that I'll need to get a new one for this repair? I think it's likely that I'll need to take it off, see what's wrong and then order any parts that are required, but I want to know if that means catching any oil, or if it means draining oil first. The service manual says nothing about oil.
1981 KZ750 LTD

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  • SWest
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Re: Identify my new engine rattle - 1981 KZ750 LTD

04 May 2017 06:43
#761141
I use a gallon oil container with the side cut out of it to catch the oil. When taking that cover off there may be a small amount of oil coming out. You will need a gasket but if you're careful you may be able to save the old one for the time being. When I did mine I had to reuse the gasket many times until I was sure I had it right. I used high temp copper silicon to seal it. I've yet to get a new gasket but will soon.
If that cover hasn't been off the screws will be hard to remove. I have Allen heads but before I used this.

Every toolbox needs one of these.

This is a larger four but the principles are the same.
Steve

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Re: Identify my new engine rattle - 1981 KZ750 LTD

04 May 2017 15:48
#761191
I've always had good success with the proper JIS bits and and impact driver for taking out the bolts. I'll give it a go on the weekend.
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Re: Identify my new engine rattle - 1981 KZ750 LTD

04 May 2017 16:52
#761195
There is no oil inside the cover on the 750/4 bikes.

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Re: Identify my new engine rattle - 1981 KZ750 LTD

04 May 2017 17:00
#761196
Nessism wrote: There is no oil inside the cover on the 750/4 bikes.

Ah, that's what I thought (since there was nothing mentioned in the manual), but since there was a gasket there and so many mentions of oil elsewhere I wasn't sure.

That will make life much easier.
1981 KZ750 LTD

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Re: Identify my new engine rattle - 1981 KZ750 LTD

05 May 2017 20:57
#761282
All fixed - perhaps the easiest repair I've ever done. One of the stator bolts had wound out and was fouling the rotor. Tightened them all up with a little loctite and no more noise. Thanks for all your help.



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Re: Identify my new engine rattle - 1981 KZ750 LTD

05 May 2017 21:22
#761284
Good thing you caught it early. Good job.
Steve

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Re: Identify my new engine rattle - 1981 KZ750 LTD

05 May 2017 21:50
#761285
Yeah, I can imagine it coming out just a little too far and shearing off completely, leaving a bolt head in there to bounce around and destroy the stator, and probably the magnetic surface of the rotor too. But it started to suddenly and sounded too mechanical to just leave it. And the fix cost me nothing except time - and I spent more time on this thread than I did on repairing it.
1981 KZ750 LTD

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