[raffaelli]

Thank you.  Good information!

[Ulfthednar]

RELATED -Similar issue.

So again on my 2022 CForce 800XC that had the injector issue.

I just replaced the Speed Sensor and RPM sensor.

Several weeks back Id had it running while tinkering on the 2023 800 and saw exactly where my coolant leaks were (the crimped tanks) and found a soldered Radiator for $129.

I havent tinkered with it too much but just instastalled the new radiator and the two new sensors.

PRIOR to this Ive never had a fan issue.

Now I do.
The FAN ITSELF works fine. I ran a couple jumpers and tested that.

burped the radiator, filled the coolant tank and so forth.

Started it up and let it run and it hit temp and the alamr went off, no fan running so I shut it down.

So tonight I tested the fan right off and checked the related components that I know about.

The engine temp sensor seems to be seated right, as does the sensor on the radiator as well as the plug for the fan.

I checked the fuse (standard mine 15 amp in the small black box) but Im not sure how to check the main relay in the big clear box.

I know the fan itself works as I tested it straight off this evening.

So, start it up, let it run, it reaches temperature normally. (time wase) but the fan never turns on, the gauge maxes out and the alarm sounds.

I can disconnect the dash and do a reset and it goes back to normal, till it reaches the temp the fan would normally turn on and it does it all over again.

I also tested this with my Other ECU (my tuned one) and it did the same thing.
It wont reset unless I unplug the dash, but it goes right back as soon as it hits "fan on" temperature, which has always been four bars on this bike.

I looked specifically for an auto fuse like referred to previously in this thread but cant find one on here.

I have NOT let the bike actually overheat or anything and it still runs just fine . . .


I was testing everything prior to testing it to see if I've sorted out the underlying issues.

but I cant proceed til I figure out why the fan isnt coming on . . . GRRRR . . .

[NMKawierider]

Just some thoughts: On the older Kawasaki's with the fan switch on the radiator, if the unit isn't completely submerged in the coolant it won't close and the fan won't come on. Is it possible there is enough air-gap to cause this. It does have to have NO airgap at all. And does the fan switch protrude into the new radiator as far as it did with the old one? And the fan switch is in the same location on the new radiator as on the only one..right? At least it is on the top or high-side somewhere where the hottest coolant is..right?
Also, if for some reason the thermostat isn't opening the radiator won't be getting any hot coolant so the switch won't come on anyway. With it running and the cap off, do you see it moving and is it actually getting hot in the radiator? Any pitched lines? 

[Ulfthednar]

Thats a very good thought on the air cavity.

So the radiator I picked up is like an exact match dimension wise and ports.
I did have to drill 4 small holes to mount the plastic guard but other than that EVERYTHING was a direct fit.
the Huge difference is that the entire thing is soldered/welded and instead of $439 it was $129. 
 (- link for those interested https://www.amazon.com/dp/B09M6YTT3X?psc=1&ref=ppx_yo2ov_dt_b_product_details -)
There is a good possibility that there is an air cavity arond the thermostat.

I did try to burp the air out, but perhaps I need to run it longer with the cap open unless someone knows a better way?
I know how to do an old V8 but Im still a newb with these new fangled machines

As far as I know, except for one instance where my plug wasn't seating right on the temp sensor on the rear cylinder Ive had no issues with running temperatures on the engine.

It has never gone over 4 bars. the fan has NEVER failed to cycle and you can set you clock by it system wise.
Four bars, on. three bars off. If the weather is warmer/hot or Ive been riding hard it will stay on four bars longer before it drops a bar and the fan stops but nothing that seemed the least excessive.

Im pretty much at the stage of "have I ferreted out my prior issues" testing before deciding if I want to pull the heads and have the valves done.

Again, I visually inspected the fuse. I could try swapping it in case there is a hairline break (Ive had those before) but visually there is no burnt or darkened plastic.
I do not see a connector with an auto reset fuse as mentioned prior on this thread but it does have a designated (15amp) fuse in the little fuse holder.
I manually tested the Fan itself by hot wiring and it runs just fine.
I did install new RPM sensor and CPU and it does seem to have really smoothed out the engine, but I couldnt really continue testing.

I did swap in my "tuning ECU" to cross check if it occured with that ecu which it did, which should rule out the control module.

But yeah, if I have an air pocket in there not allowing the coolant to contact the thermostat . . no flow to the switch. So Ill start from that posssibility next time I get to focus on it for a bit.

[Ulfthednar]

Bleeding and reseating all the connectors corrected it.

I think it was the rear head where the temp sensor is causing the issue.

Thanks for the assist on that.

Glad theres others out here that know their way around these machines.