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2016-06-16 KZ1300 Water Pp Impeller inspection


2016-06-16 KZ1300 Water Pp Impeller inspection

Decided to replace the t-stat and inspect the impeller. I had a new t-stat that the vendor said was the same as OEM. Not really, but more on that later.

Radiator and fan off.

So ask me again why I didn't take a pix of the impeller. I do have this video though. To me, it appears the impeller blades are reversed in relation to rotation direction. Look at the video. Start at 18 seconds. The impeller rotates away from the 'v' of the paddle. This seems incorrect to me.. but I'm not going to change anything. What's there to change?

Start at 18 second mark to see true rotation.

ImpellerCorrectDirection? from dcarver220b on Vimeo.


Old OEM t-stat and spring. I have a new spring too. The spring keeps the t-stat located into the head.

The old t-stat rated at 82C which is close to 180F IIRC.

Careful, mad scientist in action. Had to to do this when ms dCarver wasn't home... both t-stats work correctly. The new t-stat opens at 155F and has greater travel e.g. it opens more to allow greater flow.

Video of the test..

KZ1300 Oem T-stat from dcarver220b on Vimeo.


I used the new spring, even though the old seemed perfectly fine.

82 vs 60C.

OEM sure looks fancier.. Not sure what the preload spring on top is all about. OEM on left.

6 little rich running sparking plugs, all in a row. When the cooling issue is fixed, tuning will begin.

Looking up into the head. Now you can see why the spring is needed to keep t-stat located firmly.

Another view.


I elevated the front to hoping to release any air bubbles in cylinder rear. My bud rides KTM's and says KTM requires a 35 degree front elevation to prevent air bubbles on the 990's? Anyway, couldn't hurt.

I used a different fill technique than that in OEM service manual. Removed the temperature sensor and switch.

Was going to measure how much coolant went in. Then realized I had captured all except for a few drips when I drained it.. so the better test was to see how much went in, if not more, using the new fill technique.

The new DG 6into1 interfered fan bracket. So relived a bit of material for clearance. Hard to see here.

All right then, started filling using the temperature sensor hole.

All but this much from the drain down was in the block! This is significant, as the radiator has yet to be filled. At this point, can not see level in radiator. Encouraging, me thinks.

Temperature sender installed, now filling from radiator top cap. Forgot about the switch hole being open.. And yes, I replaced the switch connector.

All of this went back into the radiator an more. This is a different bottle than in previous pix.

Almost done.

Initial results are encouraging. Previously, she would indicate well into the red zone while just idling on a fairly normal day, about 80F. After the this fill and purge, she gets to 3/4 scale and that's it.

Here's a video of the air bubble purge.

Kz1300 PurgingAirBubbles from dcarver220b on Vimeo.

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