Exhaust Gas Temperature

[Jim Jones]

Where in the exhaust system would the EGT probe go?

There is no existing EGT on the D2-55C and Vetus wet exhaust system. So not sure where to install one.

Being a wet exhaust system, should the EGT be monitored in several places? Ie, on the exhaust manifold of the engine itself and/or further back before the water lock or muffler ?

[pjShap]

My EGT monitor installation said to place it on the exhaust hose, right after the injection elbow.

[Jim Jones]

Originally Posted by pjShap

My EGT monitor installation said to place it on the exhaust hose, right after the injection elbow.

Which EGT probe did you install and is it connected to N2K ?

[pjShap]

I installed a single-engine EGT alarm from Borel Manufacturing. It's just an alarm, no N2K networking.
https://www.borelmfg.com/products/

[Jim Jones]

Thanks for the info.

[DougR]

Typically the EGT probe is placed as close to the exhaust manifold outlet as possible, generally before any water injection. As soon as you get downstream of the water injection point you are corrupting the reading.

Frequently the injection elbow itself is modified to accept the thermocouple, or a spacer is installed between the manifold and the mixing elbow, or at the turbo outlet on a turbo engine.

On your D2-55 I think the easiest thing would be to make a spacer to go between the manifold outlet and the mixing elbow. This would require longer attaching studs. Alternatively make a custom mixing elbow and place the probe in the dry portion of the elbow before the water injection point.

[pjShap]

I guess it depends on the sensor's purpose. If you want to measure the actual EGT, it should go as described above, before the water injection. My alarm goes off if the cooling water flow fails, so it has to be downstream of the mixing elbow.

[Woody]

I have also seen a metal band clamped around the exterior of the exhaust elbow with temp readout but this is inferior to an internal sensor.

[Jim Jones]

Originally Posted by pjShap

I guess it depends on the sensor's purpose. If you want to measure the actual EGT, it should go as described above, before the water injection. My alarm goes off if the cooling water flow fails, so it has to be downstream of the mixing elbow.

That's not a bad idea actually.

Measuring the EGT of the engine is the best early warning of engine status there is. The slightest chance in engine performance/load will show up on EGT first. So as suggested for actual engine monitoring I would go with the sensor at the elbow.

However i think its also a great idea to have another further down the exhaust system to monitor temps of the hot wet exhaust - if the cooling water goes wrong it will show here immediately - a very good early warning system.

One of those actisense units or similar would take the EGT temp signal and translate it to N2K. My poor wallet is groaning .....

[Jim Jones]

Originally Posted by Woody

I have also seen a metal band clamped around the exterior of the exhaust elbow with temp readout but this is inferior to an internal sensor.

yes that was referenced early in the thread and is a non invasive way of doing it. Seems to be a good way forward if one cant do any engineering on the exhaust system.

[Jim Jones]

Originally Posted by DougR

Typically the EGT probe is placed as close to the exhaust manifold outlet as possible, generally before any water injection. As soon as you get downstream of the water injection point you are corrupting the reading.

Frequently the injection elbow itself is modified to accept the thermocouple, or a spacer is installed between the manifold and the mixing elbow, or at the turbo outlet on a turbo engine.

On your D2-55 I think the easiest thing would be to make a spacer to go between the manifold outlet and the mixing elbow. This would require longer attaching studs. Alternatively make a custom mixing elbow and place the probe in the dry portion of the elbow before the water injection point.

Thanks Doug. Will look into that and share that info with my mech.

[more]

on d2-55 10-20 cm from mixing eblow on rubber hose. reading temperature see 20-25C around 45-60 everything ok to 85C max.
special dry exhausts probe go in dry before mixing elbow