Break-in, what to expect

Searios · Feb 24, 2017

My engine is 11 hours into the break-in procedure. Mostly idle while testing other systems, and only 1 test run with varying load on the engine.

Slight amount of oil is evident in the wet exhaust water, and tiny amounts of oil is dripping from the gasket between the exhaust manifold and the exhaust riser. There is some dry sot through the gasket too so the riser bolts were obviously not tight enough.

The exhaust is generally clear, but there is some light grey/blue smoke too.

As I have never broken in an engine before I'm questioning if the this oil is normal during break-in or if I should be concerned. I'm kind of leaning towards the cylinder rings not being settled yet and allowing a little oil through -which should be burned in the exhaust, but isn't as the engine is not hot enough

BandB · Feb 24, 2017

Searios said:
My engine is 11 hours into the break-in procedure. Mostly idle while testing other systems, and only 1 test run with varying load on the engine.

Slight amount of oil is evident in the wet exhaust water, and tiny amounts of oil is dripping from the gasket between the exhaust manifold and the exhaust riser. There is some dry sot through the gasket too so the riser bolts were obviously not tight enough.

The exhaust is generally clear, but there is some light grey/blue smoke too.

As I have never broken in an engine before I'm questioning if the this oil is normal during break-in or if I should be concerned. I'm kind of leaning towards the cylinder rings not being settled yet and allowing a little oil through -which should be burned in the exhaust, but isn't as the engine is not hot enough

First, follow what your engine manufacturer recommends very carefully and closely. Normally, they expect some of what you're seeing and there's a very early service to change fluids, tighten everything again, check thoroughly.

If it were me, with what you're seeing, I would be going to the dealer/yard now and asking them to look. Perhaps they'll do some tightening now to see if it relieves your issues. Better to go get it checked prematurely than wait too long.

Running your engine at mostly idle for these 11 hours is absolutely inadvisable. I can't imagine your manual saying that is ok. Typically they call for varying speeds and not holding it at WOT for extended periods, but also not idling for extended times.

You never mention what the engines are?

Searios · Feb 24, 2017

Thx, unfortunately the lower RPM runs (up to about 2000 RPM) were unavoidable due to trying to match the CPP propeller / gearbox / engine controls / hydraulic systems during the commissioning process....trial and error type.

The 2 hour trial runs were at varying loads and definitely enough to heat up the engine's dry exhaust - as it had changed color after the tests - the CPP does that easily.

I can easily load up the engine and burn off the oil in the exhaust if required, I'm just wondering if this oil in exhaust is normal during break-in.

The engine is Iveco NEF, 6.7 liters, straight 6, 150 HP.

BandB · Feb 24, 2017

Searios said:
Thx, unfortunately the lower RPM runs (up to about 2000 RPM) were unavoidable due to trying to match the CPP propeller / gearbox / engine controls / hydraulic systems during the commissioning process....trial and error type.

The 2 hour trial runs were at varying loads and definitely enough to heat up the engine's dry exhaust - as it had changed color after the tests - the CPP does that easily.

I can easily load up the engine and burn off the oil in the exhaust if required, I'm just wondering if this oil in exhaust is normal during break-in.

The engine is Iveco NEF, 6.7 liters, straight 6, 150 HP.

Well, much to my shock the manual says no special run-in procedure other than recommending you do not run at high power for extended periods during the first 50 hours.

It says nothing about what to expect either. Others here are more technically knowledgeable than I am and will give you opinions. However, I don't find some loosening and settling to be unusual but would want it looked at and adjustments made where needed. With all the idle running, I don't find some smoking alarming. I just wouldn't at this point assume all is well, but would take it in and get it checked. Better to be safe than sorry.

If the issues continued after adjustments and during normal running, then I'd be more concerned. For the next hours after the adjustments, I would still recommend varying the load.

Searios · Feb 24, 2017

That's what the instructions says - it doesn't mention what to expect during the break-in period....so maybe it's expected to have some oil in there, I just dont know.

I'll probably just replace the gasket, tighten the riser bolts and get on with the commissioning until my 50 hours are up....

Any Iveco users out there?

Ski in NC · Feb 24, 2017

Any engine new/old/broken in/or not is going to load up the exhaust a little if run at light load.

In general, you don't want to idle it or run light load. Get it under way and load it up at varying rpm and load above 50% on both, then some quick stabs up to full power and rated rpm.

You want some pressure and heat in the cylinders to get the rings to bed in.

FF · Feb 25, 2017

IF you have a CPP install an EGT and follow the engine mfg regarding the high temperature.

You can harm an engine with overloading even quicker than underloading.

The EGT gauge will show the power level at every RPM. ( an auto one for about $100 is fine)

Searios · Feb 25, 2017

I've got Murphy thermocouples and gauges.

sunchaser · Feb 25, 2017

Is this a new or rebuilt engine? In either case have you received advice from the supplier as suggested by BB?

Initially you said the engine is not running hot enough. As mentioned by Ski in post #6 this is likely the case. Until you load the engine up for a few minutes stretching to maybe half an hour, burning at the rate of 3 to 4 gallons per hour, the rings will likely not set.

Don't dally, get it running as designed. At a 150 HP rating, full load should be around 8 gph. What do the load curves say?

Good luck.

Break-in, what to expect

Searios

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BandB

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Searios

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BandB

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Searios

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Ski in NC

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FF

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