Radiator Bleed on 308 QV

Engine should be running.

 

Get the engine up to operating temp w heater valves open, rev it a bit and then bleed . I was instructed by a good Ferrari mechanic to open the bleed screw for a few seconds at a time intermittently until the bleed is complete. If it's held open for a long period of time, it can begin "breathing" air back into the radiator. Also, recommended, raise the front of the car slightly or park on slight incline for a more thorough bleed. This forces the air to the top the radiator. He also recommend to drive the car( again, keeping the heater valves open) after the first bleed, come back, and repeat. While a blled can be accomplished OK w/o the driving or incline and some of this may be overkill, this guy is very thorough with every job he does and indicated that a more complete bleed will be accomplished in this way.

 

Good tip. That method will also make it practical to do the bleed only from the radiator screw without having to also do it at the thermostat housing.

 

Guys this so simple just think about it a little. I have been servicing Ferrari for 20 years now and other german vehicles before that.
Raise the rear of the car only open the radiator bleed screw. clamp off the small 8mm hose at the fill tank begin filling the system two gallons or so untill fluid comes out the radaitor and close. install an hand pressure pump on the coolant tank pressurize the system to 15-20psi open the the radaitor bleed screw alll the air will come out close. Now open the bleed screw at the thermostat housing and repeat. you may need to add more coolant. but you end up with little mess and no hot fluid to deal with it works every time I have done this on several vehilces and it works.

 

Another approach is to put brake bleeder screws into the bleeder holes and put clear hoses on the bleeder screws. This way you can bleed a gallon or so into a empty anti-freeze jug. May be overkill, but it will get all the air out.

Mark

 

Mark--are the brake bleeder screws the same thread as the radiator blled screws? I also had this idea for the radiator drain plug to aviod the messy gush of fluid all over the place with the stock plug.

 

Doc:
In my case the radiator screw apparently was frozen so somebody drilled and tapped a 6mm hole in the center of the plug. In your case, you will probably have to take the bleeders out & match-up at a autoparts store. I do not remember the thread size, but I'm pretty sure it was 8mm x 1mm pitch. If you choose this approach it would probably be helpfull to post what you have.
Sorry,
Mark