Another coolant issue

[Bubba Zanetti]

Hi,

I have a very similar issue to Red Falco as per below thread.

https://www.hayabusa.org/forum/busa-problems/148097-radiator-coolant-system-sucking-air.html

The expansion tank seems to fill up to the overflow with hard riding and if I syphon the excess from the expansion tank and refill into the rad it fills to the brim. There appears to be no loss of coolant.

Also the fan does not always seem to kick in when it should, just at the half way mark on the guage but due to the lovely Irish weather (see bloody freezing) it will only run up to this temp if idling in the garage for 20 minutes.

I don't like the idea a dodgey head gasket or cylinder head, is a pressure test a good place to start? Any thoughts.

Cheers.

[Bubba Zanetti]

Sorry, 2005 Gen 1 Busa, 25K miles just for info

[delbert]

All i can suggest is red through Red Falcos thread and see if there is any info there that may help you , also check pipe and in/out let to bottle are clear , replace rad cap ?
You are leaving it sufficient time to cool to draw it back to the rad ?? it can take a few hours to fully cool

[Bubba Zanetti]

Cheers for the reply.

The bike is going in this weekend to get the valves checked but I wanted to figure it out before that so I dropped the coolant out and flushed through with clean water today.

Then I filled and bled as per the manual, 3-4 cycles of running up to temp and burping. All looks good for now with the fan cutting in etc and the expansion bottle doing what it should but I won't called it sorted until it gets the official once over.

Yesterday was a weird one as the expansion tank filling right up to the top, we'll see.

[Bubba Zanetti]

All was not well it seems.

The bike went in for the valve clearances and was run on the Dyno for a "Stress Test" given the recent issues and after about 20 minute it filled the tank and spat out some coolant. F*ck!

Just to rule it out before the head came off he ran it with a new radiator cap and the issue went away. Expansion tank behaved as normal

[RedFalco]

Nice!! I love happy endings.
Hopefully I'll have the same in a few weeks.
lease:

[Bubba Zanetti]

Ah ****!!

Tank bubbling issues back.

Here is where the level is at when cold

After a warming up and a hard blast this is where it goes

I've had the stat out to check and extends fine when heated past 82 degrees C

I've also done a test with a sniffer in the radiator that should pick up exhaust gases in the coolant, liquid stays blue

Just to be stubborn I put the sniffer up to the exhaust and it does turn yellow which is not what you would like to see in the rad.

I know it's looking like a possible head gasket issue but I have no hard evidence to warrant that work yet.

If the bike is run up to temp on the stand the expansion tank doesn't go far past the full line, under load is when it fills the bottle

Any ideas?

[RedFalco]

Some serious bubblin going on at idle.
You did have the coolant system pressure tested?
In my research, head gaskets can "give" in a way that exhaust gases will not enter the system. Seeing the coolant ports run through the head first hand, I can see where that statement would be true. Being that your system runs as it should on the stand on warm up and cool down and if your coolant system pressure test is good, I'd say head gasket or cracked head.
If you do go with the head gasket, the benefits of having APE do a performance valve job and port blend are UNBELIEVABLE! The pull my bike has in 6th gear after APE did their majic is like night and day. I often catch myself looking down at what gear I'm in on the highway and cant believe I'm still in sixth gear.

Good luck to ya

[Bubba Zanetti]

Cheers RedFalco,

I'd definitely look at doing something with the valves if I need to get the head looked at, which is a distinct possibility now by the looks of it.

Local tuner to us opened up his motor at 16K miles and he said the standard valves were way past their prime.

Is the bubbling evidence enough to get the tools out and extract the engine??

What if I do all that and put the motor back it and the issue is still there (I know you had some worries )

[Bubba Zanetti]

Is one of them high pressure rad caps an option?? When I look back it only started after I put the full system on it.

[RedFalco]

In my case, the evidence was rule of deduction.
Starting with:
RadCap, ThermoStat, Pressure Test, LeakDwn Test, Changed WaterPump, Changed questionable hoses.

The majority of the opinions I recieved pointing towards the head gasket was the fact that the system acts as it should at idle and warmup but shows these symptoms after a good hard run with the bubbles.

If you went the head gasket route and did not fix it and all other components are ruled out, you could be looking at a cracked head. My fear as well when I was putting mine back together was if the issue was still there and I went through all that work it had to be a cracked head because everything else was ruled out. There was a gent that went through that very same process and chased this issue around for over a year after his rebuild to find a hairline crack in one of his valve ports.
My advise (for what its worth) would be to rule out the obvious components of the system.
When and if you go the head gasket route, send your head off to APE for a resurface and inspection to make certain it is flat and true. A Performance Valve job with Port blend will make a WORLD of differance and is a PLUS.
APEs studs and nuts for the reassurance factor towards repeat issue.

Good luck to ya Mate! I'm pulling for ya!

[Bubba Zanetti]

So far so good

Dumped the coolant out of it, flushed it out with some rad cleaner stuff.

Brimmed the rad with new coolant, ran it with the cap off, few bubbles escaped.

Stuck cap on, let it come up to temp. Let it cool down, top off the rad.

Brought for a good hard run and the expansion tank had just come to the L on the bottle, not a 1 bubble.

Not calling it sorted yet but looks promising

[wized36]

I have an 06 Busa and same thing happened to me - noticed the expansion tank full on a couple of small runs, then in traffic it actually overheated, stopped to let it cool, got home and parked overnight. Heaps of coolant on floor in the morning. Topped up radiator and expansion tank to correct levels. That was over 12 months ago and have never had the problem again, always runs in temp range and fan works correctly.

My guess is air got into the coolant system during radiator flush by previous owner.

[Bubba Zanetti]

Well lads, the problem wasn't going to fix itself so I dropped the engine out a week or 2 ago. Left it in the local shop and he stripped her down. 100% was the head gasket, there were signs of gases escaping from the centre 2 cylinders towards the inlet side.

Have the motor back in now all is as it should be.

As Red Falco said, process if elimination

[dadofthree]

Glad you got her fixed

[mrriverajr]

What did the repair cost you?

Well lads, the problem wasn't going to fix itself so I dropped the engine out a week or 2 ago. Left it in the local shop and he stripped her down. 100% was the head gasket, there were signs of gases escaping from the centre 2 cylinders towards the inlet side.

Have the motor back in now all is as it should be.

As Red Falco said, process if elimination