Broken down!

Need to find whatever is leaking first and take it from there. Could be a bad pump, could be something more sinister. Could however have just be that hose's time to die.

Get the coolant system leak tight, topped up and bled, then take it from there.

 

Hate it when they leave the snail's trail of coolant. Best of luck getting her back up. Those hoses in the top valley between the heads take a thermal beating.

 

SRI hoses or something similar are usually a semi-permanent fix with good hose clamps, and that is what it sounds like.

Home - Scuderia Rampante

 

Happen to me, it was a bad water pump. Fixed pretty quickly.

 

What happens to a water pump that causes a system to overheat as long as the belt is working and the shaft is turning? If it is not leaking have the impeller blades broken off?

 

If it leaks, the system eventually runs low on coolant and it over heats.
If the impeller broke off the shaft, there is no more pumping action and the stagnant coolant overheats because it does not make it to the radiator. It blows off the top and spews all over the place.

 

90% chance it is the fans not working right. Also have mechanic look at fusebox for burnt and melting at the junction of fan wires to fusebox. This is bad design. All smart people do aftermarket non-ferrari sanctioned repair to max fan efficiency and decrease loads on the fusebox improperly designed from factory to handle those fan loads. What is done is to take the out put of the fan wires and run to a relay so that the fans can run off the battery with proper sized wires. The OEM Ferrari fan wires are then used as a trigger of the relay. This gets the heavy power off the fusebox.

90% chance you got airbubbles to cause the heater issue.

1-get fans working properly super common failure with failure result as you describe.
2-pressure test system and if passes then:
3-fill system
4-bleed system
5-enjoy

 

If even the cabin heating is not working, it sounds like coolant flow issue. i.e. assuming your aircon water recirculation pump and valve was working prior to this problem.
I guess a main water pump could cause this, but I suppose a leak could introduce air into the system, impeding the flow. Air in the system may stop heat getting to the right bank coolant temperature sensor, thus not triggering the respective fan.

Just looking at this diagram for the aircon system, it looks like the water is supplied to the aircon hot water recirc pump via a T section on one of the radiator hoses:

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I wonder if a jammed thermostat could cause these symptoms? The thermostat allows coolant to flow to the radiator.

 

Ah.. maybe not. You also said:

I assume the thermostat would be open for there to be heat transfer to the radiator hoses. Is the top hose the outlet of the radiator?

 

fusebox: burnt and melting of junction of fan wires to fusebox
pull fusebox out passenger footwell and inspect.

 

I have seen my share of toasty fusebox .....

 

Unfortunately, that doesn't really explain why your heater isn't working. You may have a couple of issues. Was the HVAC system operating at all? Was the blower fan working?

Do youknow the assembly number of your car? It will tell me what type of HVAC system is fitted to your car.

There is a fuse (#5) in the passenger footwell called "AC Group" (7.5 amps). I believe this powers the hot water recirc pump for heating and some other HVAC items. Pump failures are also common.

 

The waterpump has a small hole so if the engine boil the cooland, the pressure is too big snd it makes the coolant pour out of the pump. From my understanding, this is a safety energency relief for the coolant system. If the fans are not working, the coolant will start to boil quite quickly. The fans must work 110% on these cars!!!

 

There is a separate pump for the heater, as well, at least on the Maranellos.

 

That is not my understanding. The WP weep hole communicates to the ceramic seal in the pump turbine. When the WP wears out the seal goes bad and the weap hole is warning that you need a new pump. You can start weeping for thousands of miles before failure but failure is coming. The weep hole is like the metal screech tab that tells you your brake pads need changing. You could have 1000+ miles by the time you hear that tab squeal.

The system pressure relief is at the cap and is around 1-1.3 bar or so. The radiator, coolant tank in the 550 case, cap has 2 functions. 1 be a cap. 2 be a pressure relief valve.

 

After a bit of sleuthing, I think the top radiator hose is the one coming from the thermostat (coolant flows when the thermostat is open). Image Unavailable, Please Login

The pump housing seems to have 5 pipes (HVAC hot water recirc pump pipe not shown above).

1) inlet from engine
2) thermostat outlet to radiator top hose
3) inlet from radiator (cooled)
4) pump outlet to engine.

When the engine is cold, the coolant just goes from 1 to 4.
When the thermostat is open, the pump appears to be sucking cooled coolant from the radiator, not (directly) pushing water through it. The motive force for pushing coolant to the radiator via the thermostat appears to be coolant flowing through the engine.

Experts?

Here's a shot of the back of the water pump housing. I'm not sure what the lower two ports are for.

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You're a very knowledgeable fellow.

 

I think we should wait to hear comments from the experts first ... There was some speculation in my message.

 

Qavion is correct. At the risk of rewording what he already wrote :

The water pump aspirates coolant from the cylinder heads, through the coolant manifolds. The pressure differential resulting from the pump's aspiration causes coolant to recirculate into the engine block through the lower port at the back of the water pump housing, whether the thermostat is open or closed.

As the thermostat remains closed during the warm up phase, the water pump pulls coolant from the manifolds and coolant will flow back into the engine block through the lower port at the back of the water pump housing, without flowing through the radiator.
As the warm up phase ends and coolant reaches the desired temperature (90°C I believe, as suggested by the dash gauge) the thermostat opens, coolant now flows through it and through the radiator to stay at 90°C in "normal" driving conditions, flows back into the water pump housing through the large upper inlet port, then back into the engine block again through the lower port of the water pump housing.

What a water pump does in any or most ICEs is to pull coolant, no push it, and in 99% ICEs, the coolant loop is designed so that coolant is pulled out of the engine from the cylinder heads by the water pump, and flows back into the block because of the pressure differential resulting from the pump running.
On a side note, the 12 port design of the coolant manifolds suggests to me that heat is being transferred from the engine into the coolant in a well-balanced manner between each cylinder - in my experience, not all ICEs have one coolant outlet port per cylinder in the heads.