[4ePikanini]

It's all good and well keeping the EGT downs on idle but the EGT could be low enough for shutdown while the exhaust manifold is still smoking hot.

I'm not having joy with a second EGT probe so I'm considering getting a CHT K type thermocouple to measure the hot side on the turbo which IMHO would be a great indicator of shutdown temps and overfuelling leading to too high temps for the engine.

The question at hand is what is a dangerous EMT (Exhaust Manifold Temp) or Turbo hot side temp?

[4ePikanini]

This guy has just been ordered

Operating Temperature : -40 – 1000 C (-100 – 1800 F)
Washer Material : Stainless Steel
Washer Thickness : 1.5 mm
Inner Diameter : 14mm (1/2”)
Outer Diameter : 19mm (3/4”)
Cable Length : 3m (10’)
Insulation : Ungrounded Type
Cable External Shielding : Stainless Steel Braiding
Cable Internal Insulation : Fiberglass

[4ePajero]

• Depending on the configuration of your exhaust manifold, I don't think there will be much temperature drop in the manifold.
• The 'hot' side of a turbo is usually made of cast iron, which is safe for very high temperatures.
• The oil in the turbo bearings is the weak link in the system. Google will reveal at what temperatures oil will burn and leave a varnish residue. The top ring of a piston is exposed to temps in excess of 300deg C, so I think any temperature lower than 300 C should be ok for shut down.
• When the engine is idling, it only takes a few seconds for the EGT to drop to less than 200 C. It will be interesting to see how long it takes the turbo to cool down to the same temp.

[4ePikanini]

jip. It's the oil in the turbo I'm worried about.

The 4m41 engine has developed a reputation for reliability and the few that had cracked pistons never showed any signs on the EGT gauges and the head was fine. Just a cracked piston.

So..... I feel I need to get some delo 400 on a steel plate and heat from underneath and measure the temps at which the oil boils/vapours/splits/varnish/combust etc.

[Transkeicowboy]

this all sound svery interesting. will definitely want to hear the results of this

[4ePikanini]

Only got the package from Hong Kong today.

Will report my findings here, but just give me some time, I got to sort out my pajero's front propshaft first.

[Nick Gibson]

Hi 4E

I came across this website with some specs for Delo 400,

http://www.caltex.com.au/productsandser ... px?ID=1639

KEY PROPERTIES
SAE Grade

15W-40

Density at 15°C, kg/L

0.886

Base No., D2896, mg KOH/g

12.2

Base No., D4739, mg KOH/g

10.0

Sulfated Ash, %m

1.4

Flash Point °C

230



Pour Point °C

-33



Viscosity, cSt at 40°C

125



Viscosity, cst at 100°C

15.1



Viscosity Index

125



Zinc, %m

0.15

I thought the flash point temp might be of interest for you regarding your EMT probe.