Hi i know this topic has been covered before but its time to do some more work on my Mk zx12r ready for warmer days and the main problem i had last year was when doing track days and playing hard with the car it was overheating, i mean the original kawasaki dials after couple of sessions started to flash.
Its currently got (from what the 3rd previous owner told me)a k10 nissan micra rad, ive fitted an override switch that i keep on on sessions and for 5 mins after switch off also i use engine ice which helped alot but still happens, ive even done snettereton with no bonnet on in pouring rain!!! and still hot!!
Whats best for me to do
1. buy performance rad?
2 .change fan to better one?
3.fit oil cooler??
4. all three??
Im an amauture builder but looking for ideas and would much appreciate any help (that includes you hellfire)pleaseeeeeeeeee

I would firstly find out if all the plumbing is correct, I've seen some installs that are plumbed incorrectly. My install uses the original bike rad which is tiny, I've never had any problems.
Is the header tank higher than the head of the engine?

[Edited on 11/2/12 by wylliezx9r]

Yes header tank is higher than head of engine (i think will check) and believe its a vw maybe polo.

have you got any ducting round the rad to force all the air through it? not a bec but that how i solved the overheating problem with my pinto. Air always takes the easiest route so if it can it will go round the rad, rather than through it

[Edited on 11/2/12 by phoenix70]

Yes there is a shroud around rad forcing air to take the rad route,
cheers Lee.

quote:

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Originally posted by Doyleee
Yes there is a shroud around rad forcing air to take the rad route,
cheers Lee.

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The fan is behind rad pulling heat away from rad ,the what i call 'shroud' is bits of tinwear around the fan i.e above and from memory (as cars been in mother-in-laws garage all winter)either side between nose cone and rad thus stopping air going round rad but forcing air through it and yes the faster i go the more the temperature reduces but i run out of track!

Just another quick one, overheating, what temps you seeing, I saw the mention of flashing light but what's the actual temp ?

Could it be a dodgy temp sender setting off a warning light or is it defiantly overheating ?

This occured to me but im using the original kawasaki guages which i presume are accurate things feel pretty hot to me so i either speed up or pull in as not to cook the head.

Think your next step is to fit a acurate temp gauge (permanent or temporary) you may be chasing a problem thats not there, either way a different fan is not the answer so that rules #2 out of your list.

hope this helps but paul a pal of mine spire sports cars.does away with the pump and fits a high flow pump Davis Craig type. this seems to work very well

cheers paul

I like to check the simplest things first, to rule them out.

You havn't wired the fan the wrong way? I did and it made the fan spin the wrong way, so it blew air through the rad the wrong way, which would have cocked things up no end if I hadn;t have checked it with a peice of tissue paper.

[Edited on 11/2/12 by Dangle_kt]

Maybe good idea to get another gauge to check accurate temp,
will look at diffferent pumps but if other people have same set up and getting no probs makes me wonder why mines not working as good?? and yes fans def sucking not blowing.

If you are 100% that the plumbing is right, have you checked the water pump?

How do you mean '
checked the water pump'

quote:

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Originally posted by Doyleee
How do you mean '
checked the water pump'

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yes sounds feasible i will give it a try did not give that a thought,
Cheers Lee.

[Edited on 12/2/12 by Doyleee]

Rather than fitting a new temp gauge you can use one of those laser type sensors on the coolant pipes, that's what the rolling roads use.

Very good idea was going to buy one anyway to check heat of wood burner any idea what temps should be looking at guessing 120 max mark????

quote:

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Originally posted by Doyleee
Very good idea was going to buy one anyway to check heat of wood burner any idea what temps should be looking at guessing 120 max mark????

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As a guide my Busa runs at around 95 water , 105 oil during a 1 hour non stop track session.

No not got manual Dangle_kt ,if you could look it up would much appreciate it
From memory the radiator fan switch opens at 93c and closes at 89c as i said its off nissan micra, I changed fan switch because was not cutting in so hence why put manual overide switch but as jon said racing at over 100mph should do more than fan would.
I dont know if this helps or not but in traffic, gauge does go up quite high sometimes flashes on hot day but blast it and cools slightly.

Lee, it sounds like you have a setup almost identical to ours and also suffer from similar problems that we used to encounter. Firstly, I wouldn't be too concerned about the water temperature gauge going mad after a few hard sessions on track. We fitted an oil temperature and pressure gauge to determine the oil temperature and set the alarm to trigger at 105 degrees. We found the oil temperature would always trigger just before the water temperature but whilst on cooling down laps and coming into the pits, the temperatures would continue to rise slightly, triggering the water temperature gauge to go berserk before cooling down again.

The modifications we made to overcome this, was to cut some vents in the bonnet to allow heat to escape more quickly and also fitted mesh with larger holes in the nosecone. We found the type of mesh fitted to the nosecone can have a profound effect on the cooling, so this may be worth looking at on yours.....

Phil

Interesting Hellfire where is best to fit oil temp and pressure gauge? what mesh is best? wanted one with no emblem and where best to place them got any pics of the above,also do you think high performance rad would change things alot?
,sorry for all the Q's wanted to get problem sorted sooner rather than later,
Many thanks in advance,
Lee.

As Phil says make sure the mesh in the nose cone has BIG holes Andy w on here had heating problems until he removed the mesh

Jacko

Most logical place to fit an aftermarket oil pressure/temperature gauge is to fit a tee-piece where the original bike oil pressure gauge is and then mount the aftermarket gauge to the spare tee. With regards to the mesh, you want something that's small enough to protect your radiator from stone strikes and the like but at the same time allow sufficient air for cooling. Just try a mesh with larger holes than what you currently have fitted.

A high performance radiator won't be cheap and there's no reason why your current set-up shouldn't work.

Phil

[Edited on 12-2-12 by Hellfire]

ZX12 motors get very hot when they are not coolant burped properly. Recheck your system that you do not have an air lock somewhere . Check your set up to ensure its routing & positioning does not incite an airlock.

Removing the oil/water exchanger will make the system run cooler but you would obviously wanna install an oil cooler which gives further opportunity to improve the oil temps too.

ZX12 motors get very hot when they are not coolant burped properly. Recheck your system that you do not have an air lock somewhere . Check your set up to ensure its routing & positioning does not incite an airlock.

Removing the oil/water exchanger will make the system run cooler but you would obviously wanna install an oil cooler which gives further opportunity to improve the oil temps too.

Ill have a look to see if pipes are routed properly make sure no kinks etc

I understand what phil is saying about letting heat escape by drilling holes but if on my last session at snetterton (new Track) i had the bonnet off in pouring rain conditions and still heating up.

Has anyone removed oil water exchanger and installed oil cooler in this or similar set-up?

Many thanks to those who have contributed to this topic it helps talking it through with others

[Edited on 12/2/12 by Doyleee]

[Edited on 12/2/12 by Doyleee]

I believe Big CC & Muzzys on their Turbo 12's do an oil filter relocation kit to fit the turbo's on the bikes. That removes the exchanger & you need only break the line from the oil filter to insert a more efficient oil cooler.

Here's my ZX10R cooling sytem plumbing



You'll need to speak to someone like BigCC to buy an external oil filter relocation kit

http://www.bigccracing.com/shop/product.asp?idproduct=302

then to the oil filter mount use one of these



that will give you thermostatically controlled feed/return take offs for your oil cooler.

fitted it'll look something like this

quote:

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Originally posted by Doyleee
No not got manual Dangle_kt ,if you could look it up would much appreciate it
From memory the radiator fan switch opens at 93c and closes at 89c as i said its off nissan micra, I changed fan switch because was not cutting in so hence why put manual overide switch but as jon said racing at over 100mph should do more than fan would.
I dont know if this helps or not but in traffic, gauge does go up quite high sometimes flashes on hot day but blast it and cools slightly.

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Thanks guys most helpful

My zx12 runs hot too, but i have a few side shots in mine that might be giving me false worries. First off i was running a 95-86 fan switch and i was noticing my fan would be on far too much so i changed it to a 95-90 which did help. But after finding out the temps posted above it looks like i need a 103-98 switch in my polo rad to allow me to monitor the fan correctly.

One other problem is im using an after market temp gauge with its sender in the top hose just before the rad, i would see 120 c on it in traffic so i checked it against the original sender (no zx12 clocks) using the table in the bikes service manual to see what the aftermarket gauge read compared to what i think is the bike clocks temp and also noting the fan switch on and off point AND with an infra red temp probe. Im still no clearer on the matter, needing to borrow the bike clocks would help some and fitting the right fans switch might do me.

I was running a 2003 engine which i didnt seem to have to many problems but have since replaced it with a 2001 engine which is the one i worry about. But one more note to give, i have plumbed the oil cooler to make it neat in the engine bay so the hot exit water from the oil cooler enters the cold return from the rad to pump hose. Looking at the service manual this it wrong, the bike setup has this hot water exit the oil cooler and enter the rad at the bottom but still needing the water to pass thru the rad to cool.

So im assuming my setup is not as effecient as the bike setup, allowing hot water to exit the oil cooler and enter the pump and engine without any cooling. As the pipe diameter of the oil cooler is 1/3 of the main hoses i can assum this means 1/3 of the hot water is never getting cooled by the rad, making the fan (which i did upgrade to little effect) less effective too.

Have you or any of the other zx12 owners run the oil cooler water exit pipe to the rad top hose or do like me to make it nice and neat?

Also check the fueling, i can but you might be running leaner than me for peak power which will make the engine run hotter.

I also replaced the thermostate but that only made me take the engine apart to remove the broken bolts on the housing .

To check flow, before starting the engine open the expansion bottle top, start the engine and you should see water that cant get past the closed thermostat run out of the thermostat housing bleed hole into the bottle, this will soon slow or stop when the thermostat opens but a slight increase in throttle should make it reapear showing good flow or pressue to push the water into the rad when hot.

Cheers moorron sorry for late reply will check water flow when get back round garage, i also bought infa-red thermometer but not used yet as mates re-doing wheels so cant move car out of garage to check it good luck with cooling yours if i get anywhere will let you know and let me know how you dget on

I found exactly the same as Hellfire when I was having similar problems with overheating of my zx12r lump,changed the mesh on the grill and cut some vents on the top of the bonnet towards the rear,made a massive different.
Apparently fitting flared section to the side panels makes a noticeble difference to,I will be doing this in due course.