Plain Jane OEM nothing to see here rebuild

[RETed]

Originally Posted by JustJeff

I'm having overheating issues with the engine.

Is this something that just started to happen?
Was the system working fine prior to this?
Any changes to the cooling system?

Here is what I've noticed so far with normal driving (not driving it hard as I'm still breaking in the engine). Temps will keeping rising and rising and when they start to pass 220 I'll pull the car over and either let it idle with the efan running and hood up or turn off the engine but let the efan run and every so often turn the engine on to cycle what is in the radiator back into the engine.

Just to eliminate the obvious...
Is the fan pulling air in the correct direction?

N/A hood was being used. While I've been driving to avoid boost as much as possible. The Hallman MBC is set to zero boost, but I need to watch how I'm driving. The OEM wastegate simply can't fully bypass. I thought that perhaps because the MBC was not allowing the engine to be in vacuum that it was contributing to heat. By that I mean it may be purging as much of the pressure as it can, it's also trying to keep pressure at zero. That perhaps rather than having vacuum having zero pressure is still pressurized compared to vacuum and thus creates heat. That theory was partially blown out of the water, I put a turbo hood on it yesterday hoping to see lower temps...and did not. (Before it is said, I'm using N/A hood until I get paint work done on the turbo hood and other parts. I keep thinking paint is going to happen and it hasn't yet.)

Just a side note...
Any type of boost control is going to end up as a bleed-off system
This means that it's next to impossible to get the boost to "zero".
You can only adjust boost down to the base spring pressure - which is most cases is going to be about 7psi - 10psi on an FC turbo with an open exhaust.

Other than obvious things where can I start looking for a cure?

1. Flushing radiator and cooling system. Should I flush the heater core seperately?
2. Testing the radiator cap. What pressure cap should a S5 13B T have?
3. Possibly a clogged oil cooler?
4. I have air pump removed and so far only a single belt alt pulley. I had a dual belt pulley with my last alt but usually only used one because of belt slipping. Never had issues with heating.

Check to see if the radiator is OK:
Get engine warmed up and then check the entire area of the radiator core to see if heat is even; if there are localized spots that are cooler, you have a bad radiator (core).
Stock rated radiator cap is for about 0.9 bar or about 13psi.
I doubt the problem is with the oil system or the oil cooler - do you have an oil temp or oil pressure gauge?

Any reason you're not running double belts?
You really should be running two.
At low RPM's (under 3kRPM), the belt should not be slipping.
If the belt is slipping, it'll be obvious - you can see the pulley slip, and / or hear it slip.
You might also see a lot of excess black dust around the area of the pulleys where the belt is disintegrating.


-Ted