Cooling problem
 

I've had a few problems with the bike over heating and running badly which I thought had been resolved.

Back in February I had the cooling system stripped and flushed through with high pressure air, there was loads of old radweld which was removed (not sure why it was there as the radiator isn't leaking)

We then fitted a new thermostat, thermo switch and a new radiator cap as the old one didn't fit properly.

Problem solved the bike was running at normal temperature again and the engine seemed fine.

I know for a fact I have a faulty temperature gauge which after a couple of minutes of running the engine goes up to 120 and stays there, my mechanic did a test on it and its definitely faulty and I'm waiting for a new one.

Last Thursday I took the bike out to get new tyres and within a few minutes she was running hot (I could feel the heat coming up through the fairing) and she was running quite rough at low revs, this is what happened last time.

The fan is cutting in ok but when I parked up and turned off the engine I could hear the coolant boiling away in the radiator! :o

Last year I owned a nc30 race bike which I took to the South of France for a 4 day trackday, the night time temperature was -4 and subsequently the water froze in the waterpump and broke the impeller drive but I didn't find this out until a couple of weeks later when I was racing at Brands, the coolant boiled over and poured out the bottom of the engine!

We then stripped the pump and found the drive had shapped in two and therefore the coolant wasn't circulating through the system.

The 888 is behaving exactly the same way as the nc30 so would it be safe to assume I have the same problem? The bike was stood for 6 years before I bought it so I'm wondering now I'm using it that stress is taking its toll on parts?

I've looked through the workshop manual and to get to the waterpump I have to remove the LHS crankcase cover, this seems quite a big job, has anyone attempted this?

I managed to fix the race bike myself but I'm not so confident about working on the 888...help!

[Edited on 26-4-2004 by Queen_gravelpants]

cooling
 

Hi
sorry to hear your having probs
Touch wood i havent had a similair problem with mine although it had only done 600 miles in 4 years.
i drained the system and then filled with a mixture of rad flush and deionized water ran it for 500 miles and filled with fresh anti freeze.
to check your pump you could bypass the rad and put both inlet and outlet pipes into a small bucket with clean water,run for a short time and see if the pump is pumping back into the bucket.
if its had radweld put in the system it may well have reduced the core of the rad so you get reduced flow through and it may have blocked the the inlets to the pump and water ways.
someone else may be able to tell you if you can use something to clear the engines water ways.
hope you sort it without to much expense
ian

Celeste, This may be long winded, but here's a few comments:
These tips will help you diagnose the most common causes of overheating and remedy them fast.
Check your water circulation. The easiest check is to start up your bike with the radiator cap removed. As your engine heats up, the thermostat should open and you'll immediately notice the flow of fluid through the radiator top with a torch. If your engine overheats and you have no fluid moving through the radiator top section, you definitely have a circulation problem.

After you let the bike cool down, you need to determine whether your thermostat or pump is at fault.
First, remove the stat and try again, you should see flow at the radiator immediately, if not – suspect the water pump.
If you suspect a thermostat fault, remove it from the engine and place it in a pan of water. Check its specs for opening temperature in the service manual (temp may be stamped on the thermostat - usually around 195oF) and begin heating the water. Note the temperature it opens with a thermometer and check it against the specs. If it opens late, partially, or not at all, it is most likely the cause of your problem.
If the thermostat checks out, but you have no flow to the radiator your water pump is bad. Unfortunately, there's not too much you can do except replace it, it runs off the cam and are not normally an issue.
Check your hoses - older hoses sometimes collapse from suction and can inhibit flow at higher speeds.
If all this comes to no diagnosis of the fault, you may have a combustion gas leak to the water system (head gasket?), therefore pressurizing the water system and blowing the water out. A radiator company can add a dye to your water which will detect carbons by a change of colour.

One more thing, remember that the fuel mixture is altered by the ECU which picks up a sensing voltage from the water temperature, so if you say the temperature always reads high, then the fuel mixture will be weakened to compensate. A weak mixture creates more heat!

One last comment I have is that as you have previously flushed the system out and noticed an improvement, it could be that some of the previous radweld emulsion has moved through the water system and could have built up in the radiator. Try taking off the rad and back-flush it with a hose pipe, or take it to a radiator reconditioner company to have tested..
:yawn:

Top reply, Pitcrew!

Just to add re the last point, I seem to recall that when Celeste got the bike it was running really rich.............possibly to disguise a long-standing problem??

One other thing, from experience if a headgasket is gone, it will pressurize the cooling system within half a minute - ie well before the thermostat should open.

Cheers
Paul

Thanks guys

I've had so many different lines of advice not sure where to start really!

I suppose its a case of flushing the system through again then stripping everything off, check the hoses and water pump and take it from there.

Looks like I'm going to be busy for a while!

fixed?
 

Hi Queeny
have you had any luck with 888
ian