Hi guys

New to this forum, I bought a 88 CBR 1000F on tuesday down at the Gold Coast it is a Jap import with only 19k klms. It sounded and rode nice when I test rode it. Noticed a small amount of coolant leak on the fairing on the right hand side under the radiator. The dealer said the bike had just been serviced and the mechanic said it was just overflow. Not being able to access the radiator cap or really any of the motor I took the dealers word for it. I rode the bike back to Brisbane from the Gold Coast with no signs of over heating, the bike rode nicely with more than enough power for me. Today I decided to take the fairings off and do a general check over of the bike and see if I could see where the coolant was leaking from. I found the leak was coming from one of the hoses that had a spring clamp on it. So I pulled the hose of and caught the coolant in an ice cream container, it was then that I noticed a blue substance sitting on the top of the coolant it is obviously oil.
Do you think it is the head gasket?
Can the head be removed with the motor still in the bike?
Is this a job able to be done for someone with reasonable mechanical knowledge?

Thanks in advance

 

The first thing to do would be to drain the cooling system and flush it absolutely clean, preferably with very hot water. Then put in new coolant and just hope it is fixed. Since the bike is new to you there can be several reasons to the oil in the coolant and it is worth a try to just change the coolant.

If the problem remains, and especially if there is sign of coolant in the oil, something has to be done. Some oil in the coolant is not a big problem in itself.

I have not pulled the head on a Cane but have read in the manual that the head can be removed with the engine in place. There is a lot of free space around the head so it should be fine. I removed the head on my Blackbird, it is very tight but could be done anyway. On that bike the engine has to be tilted forward but this should not be the case with Canes.

 

Thanks R1000

I will give that a go before I pull anything apart.
There is no sign of coolant in the oil.

 

I would be having a little talk with the dealer and his "mechanic". That's B.S.

Sure sounds like a head gasket.

Good luck.

 

Hi Again,
Just thought I would let you know how things have progressed. I did what R1000 suggested and flushed the cooling system out with a radiator cleaner.. A lot of scale and rusty water came out I also cleaned the overflow container out which was also full of rusty type sludge. Whilst running the cleaner through the system with the motor running I noticed the thermo switch is faulty as the fan would not come on as the temp moved up to 3/4 but would intermittantly come on at 1/2 temp. After cleaning out the system and refilling it with coolant I ran the engine and manually earthed the thermo switch when it reached 1/2 temp. The motor sounds fine, The temp is ok, The plugs look fine. No bubbles in the water whilst running. The next thing to do is take it for a run and check the coolant for oil in a week or so.
Just a question that may help me to understand wtf is going on.
If the head gasket was blown and oil was getting into the cooling system would coolant also get into the oil?

Thanks

 

You just about answered your own question. You already know that the high pressure from combustion could leak into the coolant. If your oil pressure is, let’s say 60 PSI and there is breach between the oil and coolant, oil would pass into the coolant when the engine was running and cold. As the engine heats up and the radiator cap keeps pressure on the system, the coolant could be athigher pressure than the oil at idle and leak in the other direction. If the leak is small enough, nothing may pass until high enough pressures exist and/or the head heats up and expands creating the passage for the leak.

Sometime those bubbles you talk about are not seen until you reach full operating temperature.

I have at times loosened and re-torqued a head to seal small oil or coolant leaks. You can’t do that with a combustion leak because the leak burns the gasket like a blow torch.

Good luck
EDIT: SP

 

If there is a corrosion leak in the upper part of the engine between water and an oil channelat the head sealingsurface, it is not sure there will be water in the oil. The oil pressure is higher than the water pressure and engine oil can temporarily held a large amount of water that boils away during normal driving.

Take it calm and see what happens in the coming weeks. There could have been some oil in the container that was used to fill coolant or there could have been a mix of incompatible coolants that later separates in the system. The engine can also have been temporarily overloaded at some occasion and it isnot sure the problem is permanent. This is wish-thinking of course but there is no reason to open the wallet yet.Mechanics change dimensions with temperature and it is not for100 % sure that the problem will return. In case the problem remains it is just to remove the head, inspect the surfaces, mill them if there is corrosion damage and installa new head gasket. Small corrosion scars can be filled by head gasket sealant to avoid milling.

Was there any brown cream like stuff(like light mustard) in the expansion reservoir ?Did it feel and smelled like oil ?

 

The brown stuff in the resevoir was a rusty color, where as the oil found in the coolant was a clear to blueish colour. What in a alloy motor rusts?

Thanks again to the replies been very helpful especially as things look very dire when you discover something like this only after one ride.

 

Hmm, rusty color perhaps there is no oil at allin the coolant then [sm=smiley1.gif]. Well, lets se what happens in the future. Perhaps the rust comes from the outsideof the cylinder steel sleeves, in such case it is nothing to worry about. It is important to change the coolant periodically; the corrosion protection disappears with time and there will always be contaminations that could reduce the radiator capacity.

 

Went for a ride today and give the bike a good run. Geez these bikes are nice to ride I am very happy with my choice and can see why guys on here love their cane's. There was no sign of overheating and was able to wind the bike out to 10k a couple of times with no hesitation from the motor. I checked the coolant after it cooled down and there was no sign of oil. Fingers crossed I will keep an eye on it and hpefully it was something silly the previous owner did.
Thanks again to you guys and especially R1000 who got me to check the simple things first instead of looking at worst case scenario which I was sure was going to be the head gasket.