busa question!!!!

[NakedTurboBusa]

Before i fuck around and take my bike apart this close to AFR.... would my thermstat not opening cause undue pressure in my radiator and cause the cap pressure valve to open and force 500ml of coolant into reserve tank....The gauge does not go above half ever. But my thermo fan has not turned on, I installed a fan switch, checked the stock switch in the radiator...Electrics are fine.. I have checked temp sensor a few months ago, Ok.

Am I barking at the wrong bitch

Please advise..

Pete

[derangedrover]

Dodgy thermostat will cause overheating and subsequent pressure rise in the system, but if your not running hot the only things to look at are the cap itself, ie weak spring, dodgy seal etc, or blown head gasket.
An incorrectly bled cooling system can also show this sort of problem when trapped air causes localised boiling and associated pressure rise, but if you havent recently changed coolant I would be betting on the first two.

Cheers
Daryl

[shift1313]

have you re routed any of the cooling lines? what about a vent, or is the system totally sealed?

[Booster]

Busa's are bad for traped air. as Derangerover said air causes localised boiling, top it up , run for a while with the cap off and keep topping .even stand the bike up then put back on the sidestand several times
If it does it when quickly when under boost without getting hot i would begin to wonder about the head gasket, has it had studs,big bolts or the oem bolts torqued higher?

Mine did it intermittantly and i knew the gasket was slightly blown but i had run 10psi on pump several times and heard it ping when it was std compression.when i pulled it down the gasket was only slightly discoloured on one cyl near a water gallery, that was enough..

[NakedTurboBusa]

Booster, cheers mate,

can u explain more about getting doing it ( i asume you mean build presure and open cap valve ) quickly under boost, How quickly.... I cant tell only when ive stopped and look in the resivor..

Is there a way of checking head gasket without removing head.... will a radiator pressure test aid anything.....

thanks again

Pete

[Booster]

Probably the best test for a gasket problem is a chemical test, but it won't pick up if its only leaking at high cyl pressures (boost)
check around your local workshops to see if any have the test kit , more likely in a car based business.

blown gasket will fill the reservoir quickly, quick blast up the road and look in the res..the level may rise a little due to heat expansion if it raises a lot there may be a gasket prob.

thermostat problem would usually cause overheating showing on the gauge but not nessasarily hot in the fan switch area.

[NakedTurboBusa]

Thanks mate... I will get on it ..

Pete

[NakedTurboBusa]

Hey booster

If its head gasket....Im thinking that a longish ride on boost (2 hours) will fill the resivor and overflow it???

[Booster]

Depends how bad it is,open road stuff will not be very high cylinder pressures.
Go for a 1/2 hr ride up a freeway and see how it responds, city traffic could just be causing you heat and normal expansion..

[NakedTurboBusa]

Cheers Mate. your help has been sweet...

[Booster]

At least my doing a headgasket is good for someone ;)