Hayabusa heating

[BlueBacon]

Radiator cap failed the test. It's 1.6bar and wouldn't even hold 10PSI...

[BlueBacon]

Well...good time me, the thermostat works too.

[sixpack577]

So...she has still been reaching hot temps (3/4 -red on temp gauge) when stopped for about 10 mins, but on Friday the frame burned the back of my thighs. Stuck in 5MPH traffic on interstate and was pushing her along...less than 80F outside.

Fan kicks on at the middle mark on the temp gauge. The cap appears to be working as it is...there is excess fluid in the expansion bottle after a ride and back to normal the next day. There has been no noticeable fluid loss since originally putting in the fluid a few years ago->the last post 8 months ago->now. There has also been no color changes. Coolant is still translucent blue and oil is still dark. To me: that rules out any leaks period...head gasket, hoses, water pump seals, etc.

I'm pulling the thermostat by no later than this weekend...I'll test it in a pot of water and run the bike without it to see if it changes anything. Outdoor temperature is going to be 60-80F so I'm not concerned about it taking the extra time to reach operating temps.
Mechanic at work advised he should have a tester for the radiator cap. Anyway to check the water pump? I figured I could simply put the upper radiator hose in a bucket and see if it pushes coolant out at idle. Far as I can tell the pump is just a metal impellor on the same shaft as the oil gear...anyway the shaft could be moving, but not the gear/impellor? Anyway to check oil pressure since the two are connected?

Sounds like it's just the cap.

As far as the waterpump goes, it has a weep hole, so if one of the inner seals fail, you'll see coolant drip under it.
Otherwise, the hardened shaft would have to break, or break the back of the impellar gear for it not to pump, which though not impossible, I have never heard of it happening.
And, in the one in a million chance it did, no circulation would have the bike boiling over in just a few minutes of idling.
I would be confident you have found the problem with the cap failing the test.

[BlueBacon]

Sounds like it's just the cap.

As far as the waterpump goes, it has a weep hole, so if one of the inner seals fail, you'll see coolant drip under it.
Otherwise, the hardened shaft would have to break, or break the back of the impellar gear for it not to pump, which though not impossible, I have never heard of it happening.
And, in the one in a million chance it did, no circulation would have the bike boiling over in just a few minutes of idling.
I would be confident you have found the problem with the cap failing the test.

I also have a hard time believing the waterpump/oil gear is bad..I figured I would be hearing a whole lot of metal banging around if it was!
New OEM style cap (1.1bar) passed the pressure test. Before I put this all back together, anyone have a link to a Gen1 thermostat with a lower threshold? This one is rated at 82°C, but isn't actually fully open until almost 93°C (200°F)

[sixpack577]

I also have a hard time believing the waterpump/oil gear is bad..I figured I would be hearing a whole lot of metal banging around if it was!
New OEM style cap (1.1bar) passed the pressure test. Before I put this all back together, anyone have a link to a Gen1 thermostat with a lower threshold? This one is rated at 82°C, but isn't actually fully open until almost 93°C (200°F)

You wouldn't nesacerily hear anything at all.
The hardened shaft driven off the engine internally could snap(and if so it would be a 99% chance that the part(s) were flawed since new and finally gave up)
but the weaker link would be the aluminum impellar gear.
If that snapped were it slips into the shaft, the shaft would just continue to spin with the broken aluminum 'key' stuck in the end, and the gear unable to spin(same thing on the engine side of the shaft, only it also connects to another hardened part, which is why the aluminum pump gear is the weakest part and the spot most likely to break).
Again, never seen or heard of it, but it's not impossible.
But still, once that happened, coolant would stop circulating, and you would quickly have an overheating issue, and not just running hot, but boiling over at idle.

[BlueBacon]

ALRIGHT---please help me solve this once and for all
Bike is still climbing the temp gauge and it's not even 85F outside. I pulled the fairings yesterday and I'm not riding until I test or attempt a solution with this cooling issue.

How do I open the water pump assembly? I can find info on removing the entire pump, but not taking it apart for repair/inspection. It's the only thing left besides a physical blockage, or coolant getting in the cylinders.

EDIT: The pump is moving coolant, but I have no way of knowing if it is the correct flowrate. I started the bike while the thermostat housing was removed since I re-tested the thermostat...I'd like to pull it apart and physically see if anything is deformed, broken, etc.

[sixpack577]

ALRIGHT---please help me solve this once and for all
Bike is still climbing the temp gauge and it's not even 85F outside. I pulled the fairings yesterday and I'm not riding until I test or attempt a solution with this cooling issue.

How do I open the water pump assembly? I can find info on removing the entire pump, but not taking it apart for repair/inspection. It's the only thing left besides a physical blockage, or coolant getting in the cylinders.

EDIT: The pump is moving coolant, but I have no way of knowing if it is the correct flowrate. I started the bike while the thermostat housing was removed since I re-tested the thermostat...I'd like to pull it apart and physically see if anything is deformed, broken, etc.

The waterpump works or it doesn't, and leaks or it doesn't(it has a weap hole in the bottom like a car waterpump, so if a seal fails inside, there is a leak path to the weep hole to let you know).
The waterpump is also direct drive, so as long as the bearings have not seized, then the impellar shaft still spins freely, and the impellar shaft is driven off of the shaft inside the crankcase, so flow rate only changes with rpms, and cannot fail otherwise.
With the waterpump in hand, you can spin the shaft, and look into the hose inlet and outlet and see the impellar spin.
So the waterpump is not the problem.
Make sure the small hole in the thermostat body is at 12 o'clock, otherwise it can make bleeding the air out much more difficult.
Otherwise, it seems most likely that you have a failing head gasket, which sucks, but is still very doable with basic tools and a small budget.

[BlueBacon]

The waterpump works or it doesn't, and leaks or it doesn't(it has a weap hole in the bottom like a car waterpump, so if a seal fails inside, there is a leak path to the weep hole to let you know).
The waterpump is also direct drive, so as long as the bearings have not seized, then the impellar shaft still spins freely, and the impellar shaft is driven off of the shaft inside the crankcase, so flow rate only changes with rpms, and cannot fail otherwise.
With the waterpump in hand, you can spin the shaft, and look into the hose inlet and outlet and see the impellar spin.
So the waterpump is not the problem.
Make sure the small hole in the thermostat body is at 12 o'clock, otherwise it can make bleeding the air out much more difficult.
Otherwise, it seems most likely that you have a failing head gasket, which sucks, but is still very doable with basic tools and a small budget.

10-4, I'll remove the water pump this afternoon and see what I find out. I agree that is seems to either be the waterpump or head gasket...I'm likely going to go ahead and order silicone hoses just for giggles since I'll be dumping the coolant anyway

RECAP:
All electronics appear to be working correctly (temp gauge and thermoswitch + fan).
Thermostat is in the correct orientation and has the small hole up top.
Coolant is blue Engine Ice and is still clear blue...I don't appear to be losing coolant (or oil), no smoke from tailpipe, no discolored oil, and no "rough running" issues when riding or at idle.
Cap was replaced last year with OEM and I do have fluid moving to/from overflow, so it is working.
Does not overheat when moving...even at 20MPH.

Regardless of the water pump being good or not, I'm going to dump out the coolant and run distilled water to flush out the current Engine Ice before putting anything back together. Fairings are going to be off for at least 2 weeks because I have to replace the oil line on the right side

[202mphbusa]

does you fan have a shroud?
Missing pieces makes the electric fan far less efficient

[LC4CARL]

"Does not overheat when moving...even at 20MPH."

Perhaps by-pass the radiator fan switch so it's on all the time (confirm getting full voltage), then idle the bike to see if it can keep up? Dunno.

[BlueBacon]

does you fan have a shroud?
Missing pieces makes the electric fan far less efficient

Still have it, but good call!
@sixpack577 how much of the impeller should I see? I can  BARELY peek the tip of it

I believe this is from the OUTPUT spout. Shaft freely spins, no noise, all bearings appear to be present and good.

[LC4CARL]

At the pump output, the vane appears to have quite a bit of clearance.

[BlueBacon]

At the pump output, the vane appears to have quite a bit of clearance.

View attachment 1711459

That makes sense for why I can barely see it then. For anyone finding this in the future: the stock waterpump impeller is metal!

Well, I'm at a loss of what else I can really do besides a 2nd fan. I found 2003+ gsxr1000 and 1st-3rd gen busa fans on Ebay for under $100. I'd rather get something newer just due to the aging of plastic and electronics since NONE of these will have a shiny Muzzy blade...any preferences from the group? I've seen a mix of 2gen busa and early GSXR fans from @GIXERHP but the big selling point for those were Muzzy blades. There is only 1 Muzzy blade on Ebay and it's for a 1st gen R1

[Bumblebee]

At the pump output, the vane appears to have quite a bit of clearance.

That makes sense for why I can barely see it then. For anyone finding this in the future: the stock waterpump impeller is metal!

Well, I'm at a loss of what else I can really do besides a 2nd fan. I found 2003+ gsxr1000 and 1st-3rd gen busa fans on Ebay for under $100. I'd rather get something newer just due to the aging of plastic and electronics since NONE of these will have a shiny Muzzy blade...any preferences from the group? I've seen a mix of 2gen busa and early GSXR fans from @GIXERHP but the big selling point for those were Muzzy blades. There is only 1 Muzzy blade on Ebay and it's for a 1st gen R1

There's good reason why Suzuki added that second fan to the Gen 2...

Hopefully that solves your issue....

[LC4CARL]

If she's cool at 20 mph, and hot standing still, I'm leaning towards the fan. That said. My Muzzy single fan does the job.

I don't know if the metal fan moves more air than the plasitic unit. Or just resists deformation better.

Is the fan getting full voltage? Perhaps run power direct from the battery and see if she idles cool.

[BlueBacon]

If she's cool at 20 mph, and hot standing still, I'm leaning towards the fan. That said. My Muzzy single fan does the job.

I don't know if the metal fan moves more air than the plasitic unit. Or just resists deformation better.

Is the fan getting full voltage? Perhaps run power direct from the battery and see if she idles cool.


View attachment 1711463

that is possible...hadn't bothered since it is noticeably loud when it kicks on, but is worth checking. My stock is muzzy, thank God

[oldgixxer]

Two suggestions as my '00 Gen1 ran hot at one point as well:
-RCC Turbo's Fan Temp Switch Relocator: turns the fan on sooner&stays on longer

-dual fans on rad with a manual toggle switch that allows you to turn fans on when you get jammed up in traffic or as soon as you see the needle start to climb on the gauge

If you have a head gasket issue then this would just be a Band-Aid but if not,those two things will definitely help your situation

[BlueBacon]

2nd gen fan or 3rd gen? I know ill have to fab at least 1 mount, wiring, etc...but I can get a 3rd gen right fan for $50.
I'm open to other fan suggestions...no muzzy blades found except first gen R1. Not keen to trust a fan motor that old :/

[LC4CARL]

Two suggestions as my '00 Gen1 ran hot at one point as well:
-RCC Turbo's Fan Temp Switch Relocator: turns the fan on sooner&stays on longer

-dual fans on rad with a manual toggle switch that allows you to turn fans on when you get jammed up in traffic or as soon as you see the needle start to climb on the gauge

If you have a head gasket issue then this would just be a Band-Aid but if not,those two things will definitely help your situation

Pretty slick.

[oldgixxer]

2nd gen fan or 3rd gen? I know ill have to fab at least 1 mount, wiring, etc...but I can get a 3rd gen right fan for $50.
I'm open to other fan suggestions...no muzzy blades found except first gen R1. Not keen to trust a fan motor that old :/

TBH,I did the dual fans so long ago I think its actually a K5/6 1000 fan I had laying around w a Muzzy blade. Definitely not a Gen2/3 fan. The rad is currently sitting on my workbench,I can post a pic if you want just lmk