Hi,

strfyr51 wrote:

Years ago we had problems with the CFM-56-2 and the -3's We figured out the fuel nozzles were clogging and leaking and failing due to being coked up. We instituted an engine wash program which cleaned the fuel nozzles and all of that ended. But only after having changed 100's of fuel nozzles first

a) How do you clean the fuel nozzles from carbon deposits? using regular compressor wash, in engine shop (combustor casing removed), through spark plug holes, or through connecting the cleaning liquid hose with fuel line upstream the fuel nozzles?

Modern engines have engine wash (called also compressor wash mostly because the goal is to clean the compressor blades) even though the cleaning liquid pass through the gas path of the engine. If I am not mistaken, in some old engines like JT8D the combustors were cleaned through spark plug holes (through the combustors casing)

b) Why modern engines are not subject to cleaning through the spark plugs as older engines such JT8D?

c) Are combustor and fuel nozzles on modern engines are less prone to carbon deposits than the older engines or the current compressor wash (modern wash equipment) is efficient to remove the carbon deposits?


d) I am wondering if the AMMs (aircraft maintenance manual) recommend the use the borescope to inspect for carbon deposits in the combustor and the fuel nozzles or not?

Feedback appreciated.

Fuel nozzles aren't cleaned with a compressor wash; they're removed and ultrasonically cleaned in some cases, and via other means in other cases, often overhauled as part of the process. I've worked with some fleets in which every inspection interval, we removed the nozzles and sent them out for overhaul, and installed an overhauled set.

Turbine engines don't use "spark plugs," but ignitors, and given the lack of cylinders, typically only have two ignitors. Ignitors are located aft of the compressor section.

Carbon deposits are a problem for turbine blades, not compressor blades, as a rule, but compressors can get dirty and lose efficiency.

Washes are done in several different ways, depending on the engine, and the specific procedure to be used. In some cases, an abrasive media is released through the engine, such as ground walnnut shells. Others are soap or chemical rinses, often put in through bleed lines or taps.

Borescope inspections are done at intervals to look at blade erosion and other concerns; these inspections are often conducted through ignitor plug holes and other access points.

Not really sure what kind of engine washing this is, but here's an example of one anyway.

https://www.youtube.com/watch?v=JvdK46bcqzc

Hi: The engine wash displayed, a system developed by PW for any a/c -engine combination, use only water, which is heated, filtered and “de-ionized, for more effective wash and not secondary effect as with abrasive. This method recover used water and reused again after passing it by a series of filter and heater, for that reason is called Eco-power.. This system, after each cycle, control how deep engine was cleaned, measuring particles concentration in the water exiting the engine.
You will surprised on how clean is the water after 3 cycles (or 4 if engine is seriously contaminated
This proccedure need and cold start cycle to be performed, so, as per Manufacturer, You are limited by number of cycles to be performed, and, due that an engine run after last cycle is requiered and as time is a scarce resource, to keep fleet’s engine clean, it is better to organize process to adjust to recomended by Manufacturer time between cleanings.
There are clear registers on how FF is reduced after compressor is washed use this method and, more important, how EGT margin increases, thus keeping engine on wing more time....
Rgds

Aerotech777; Good Evening.
Problem with cleaning engines by ignitors is that this way, Fan, LPC And HPC are bypassed and not cleaned.
A clean compressor give a more effective engine.

Rgds

Aerotech777; Good Evening.
Problem with cleaning engines by ignitors is that this way, Fan, LPC And HPC are bypassed and not cleaned.
A clean compressor give a more effective engine.

Which engine/aircraft do You speak about (if it possible, please)
Rgds

Hi: The engine wash displayed, a system developed by PW for any a/c -engine combination, use only water, which is heated, filtered and “de-ionized, for more effective wash and not secondary effect as with abrasive. This method recover used water and reused again after passing it by a series of filter and heater, for that reason is called Eco-power.. This system, after each cycle, control how deep engine was cleaned, measuring particles concentration in the water exiting the engine.
You will surprised on how clean is the water after 3 cycles (or 4 if engine is seriously contaminated)
This proccedure need and cold start cycle to be performed, so, as per Manufacturer, You are limited by number of cycles to be performed, and, due that an engine run after last cycle is requiered and as time is a scarce resource, to keep fleet’s engine clean, it is better to organize process to adjust to recomended by Manufacturer time between cleanings.
There are clear registers on how FF is reduced after compressor wash and, more important, how EGT margin

So sorry for duplicate post, I don’t know why.
Should check IPad AMM or do a troubleshooting

Rgds

Additional info: Borescope inspections are accomplished by removing borescope inspection plugs from the compressor and turbine cases. On the 787, during NAMS (Nautical Air Miles) Testing we would remove the borescope plugs and borescope the compressor and turbine blades prior to every flight. You might say that NAMS Testing was a verification of the aircrafts fuel efficiency. (MPG)

On production aircraft, engine washes and borescope inspections are part of the ongoing maintenance requirements by the operator to maintain an engines efficiency and to catch blade or other failures prior to them happening.

As an aside, while contracting at an MRO I showed up for work late and reported to the lead in the aircraft. At the time, they were doing engine washes on a 747 and while the people were down stairs spraying water into the engine, the lead had set the engine to motor and was walking around the upper deck doing a maintenance card. He handed engine washing over to me when I showed up and about 30 seconds after I took over, the starter on the engine being washed disintegrated.

If anyone in upper management had 2 brain cells to rub together, I would have had to start looking for new employment.

Thanks guys for your replies.

I am a former AMT, so I am little bit familiar with jet engines and ignition system in the jet engines. It is my bad, I should say igniter plugs instead of spark plugs. I know the combustion in jet engines self-sustains but the ignition is turned on certain critical phase of flight such take off, heavy rain/hail, or turbulence if I am not mistaken.

When I mentioned that cleaning of the combustor and fuel nozzles in JT8D through the igniters plugs, I meant that this cleaning was done in the same time as the compressor wash. I didn't meant that combustor cleaning was a substitute of the compressor wash.

The person in the quote (strfyr51) said " We instituted an engine wash program which cleaned the fuel nozzles and all of that ended ". So I am wondering if the fuel nozzles and combustor (even turbine) are cleaned from carbon deposits with only a regular compressor wash (including detergent or solvent).


More replies to my questions are appreciated especially from persons who performed and/or still performing compressor wash OR fuel nozzles (mentioned by strfyr51) or combustor (through igniter plugs holes) cleaning if it is done along with compressor wash.


Thanks,

The lead could have been looking for a scapegoat, i.e., he knew the engine wash was FUBAR.

Thanks guys for your replies.

I am a former AMT, so I am little bit familiar with jet engines and ignition system in the jet engines. It is my bad, I should say igniter plugs instead of spark plugs. I know the combustion in jet engines self-sustains but the ignition is turned on certain critical phase of flight such take off, heavy rain/hail, or turbulence if I am not mistaken.

When I mentioned that cleaning of the combustor and fuel nozzles in JT8D through the igniters plugs, I meant that this cleaning was done in the same time as the compressor wash. I didn't meant that combustor cleaning was a substitute of the compressor wash.

The person in the quote (strfyr51) said " We instituted an engine wash program which cleaned the fuel nozzles and all of that ended ". So I am wondering if the fuel nozzles and combustor (even turbine) are cleaned from carbon deposits with only a regular compressor wash (including detergent or solvent).


More replies to my questions are appreciated especially from persons who performed and/or still performing compressor wash OR fuel nozzles (mentioned by strfyr51) or combustor (through igniter plugs holes) cleaning if it is done along with compressor wash.

WPvsMW wrote:

The lead could have been looking for a scapegoat, i.e., he knew the engine wash was FUBAR.

If your referring to my last post, wasn't anything that sinister. The lead was a good person, he just didn't think letting an engine motor unattended while he worked a task card on the upper deck was any kind of a problem.

I'm glad it wasn't sinister.

stratclub wrote:

The lead was a good person, he just didn't think letting an engine motor unattended while he worked a task card on the upper deck was any kind of a problem.

I don't think I've ever operated an aircraft with a starter, that didn't have a starter limitation and a duty cycle. How is it possible that a mechanic working on that equipment, let alone a lead, isn't aware of a starter limitation?

747Whale wrote:

stratclub wrote:

The lead was a good person, he just didn't think letting an engine motor unattended while he worked a task card on the upper deck was any kind of a problem.

I don't think I've ever operated an aircraft with a starter, that didn't have a starter limitation and a duty cycle. How is it possible that a mechanic working on that equipment, let alone a lead, isn't aware of a starter limitation?

Ya, I thought that was pretty bazaar at the time. I must of been in shock at the time and didn't even mention it to anybody. With so much maintenance being off loaded to MRO's, quality can sometimes be hit or miss at some of those MRO's.

Almost all gas turbine aircraft have a pneumatic starter with a duty cycle. Your 747's did. Talking about duty cycles. The 787's has VFSG's (Variable Frequency Starter Generator's) and it's duty cycle is 3 minute at 100% load and 30 minutes at 50% load. I thought that was just one of the many amazing things about the 787.

Hello: [Quotte: don't think I've ever operated an aircraft with a starter, that didn't have a starter limitation and a duty cycle. How is it possible that a mechanic working on that equipment, let alone a lead, isn't aware of a starter limitation? Unquotte].

As explained, If client don’t use to clean engines with frequency recomended by Manufacturer, and do it only, for instance when he want to lower EGT to get a higher EGT’s margin, starter cycles or engine cycles will no suffix for the process to be completed ,because there I to much contamination, as messured for water’s particles content. In that case, what is established is to wait for a long time and start another start’s cycle, but this time delays between cycles, use to affect fleet’s schedule, and are considered a no-no.
So the Leeds is responsible for have Engine no proper cleaned (look at glass with water, it is clear a full of particles water.) with will be logged in Log Book by cleansers that want to escape without damage from such fight, so lead prays and start another cycle after 15 min and.... a starter goes u/s
As lead mechanic is not a B747 captain and is highly disposable, he tray to arribe to a compromise, not always he succeed

Rgds

I appreciate the very difficult to understand cuban interpretation.

I have nearly four decades experience as an aircraft mechanic, inspector, and multiples as a director of maintenance. I understand a compressor wash.

You quoted me, or at least my words, so apparently are speaking to me. I'm also a former Boeing 747 captain.

My statement was that I haven't seen an aircraft that uses a starter (there are aircraft that don't, of course) that does not have a starter limitation. It was in reference to a poster who saw a starter motor destroyed by a mechanic who claimed he didn't know a starter had a limitation.

No, the mechanic does not need to compromise. Nor should he. The starter has a limitation for a reason, and it is neither in the discretion of the mechanic nor pilot to exceed that limitation. A pilot or mechanic who does not know the limitations of equipment has no business operating it.

Hello: I do not understand it, I had participate in several ones.
After each cycle, a clean Glass is filled with water that had passed the whole engine. Them with special tool, similar to a digital thermometer, and revolving the taken water, till, without removing the probe, You read Quantity of contaminated particles.
In an engine cleaned regularly, 3 cycles will be enough
After that, contamination is proportional to flight hours and where this a/c use to flight.

Who read contamination values and noted in LB, is the lead AP from ECO Power, and He knows that is contamination is high, EGT margin will be lowered.and for that reason will ask to perform another cycle.but, time, schedule, ....
Rgds

aerotech777 wrote:

Hi,

strfyr51 wrote:

Years ago we had problems with the CFM-56-2 and the -3's We figured out the fuel nozzles were clogging and leaking and failing due to being coked up. We instituted an engine wash program which cleaned the fuel nozzles and all of that ended. But only after having changed 100's of fuel nozzles first

a) How do you clean the fuel nozzles from carbon deposits? using regular compressor wash, in engine shop (combustor casing removed), through spark plug holes, or through connecting the cleaning liquid hose with fuel line upstream the fuel nozzles?

Modern engines have engine wash (called also compressor wash mostly because the goal is to clean the compressor blades) even though the cleaning liquid pass through the gas path of the engine. If I am not mistaken, in some old engines like JT8D the combustors were cleaned through spark plug holes (through the combustors casing)

b) Why modern engines are not subject to cleaning through the spark plugs as older engines such JT8D?

c) Are combustor and fuel nozzles on modern engines are less prone to carbon deposits than the older engines or the current compressor wash (modern wash equipment) is efficient to remove the carbon deposits?


d) I am wondering if the AMMs (aircraft maintenance manual) recommend the use the borescope to inspect for carbon deposits in the combustor and the fuel nozzles or not?

Feedback appreciated.

the LIX wash system we used flushed all kinds of soot and Carbon out of the engine, It took a long time but it's now used to restore engine performance. It will restore proper Spray pattern to the Start Nozzles and clean the total Gas Path, I just wish I'd have invented it!!

aerotech777 wrote:

Hi,

strfyr51 wrote:

Years ago we had problems with the CFM-56-2 and the -3's We figured out the fuel nozzles were clogging and leaking and failing due to being coked up. We instituted an engine wash program which cleaned the fuel nozzles and all of that ended. But only after having changed 100's of fuel nozzles first

a) How do you clean the fuel nozzles from carbon deposits? using regular compressor wash, in engine shop (combustor casing removed), through spark plug holes, or through connecting the cleaning liquid hose with fuel line upstream the fuel nozzles?

Modern engines have engine wash (called also compressor wash mostly because the goal is to clean the compressor blades) even though the cleaning liquid pass through the gas path of the engine. If I am not mistaken, in some old engines like JT8D the combustors were cleaned through spark plug holes (through the combustors casing)

b) Why modern engines are not subject to cleaning through the spark plugs as older engines such JT8D?

c) Are combustor and fuel nozzles on modern engines are less prone to carbon deposits than the older engines or the current compressor wash (modern wash equipment) is efficient to remove the carbon deposits?


d) I am wondering if the AMMs (aircraft maintenance manual) recommend the use the borescope to inspect for carbon deposits in the combustor and the fuel nozzles or not?

Feedback appreciated.

a compressor wash and a LIX wash are two entirely different things A LIX wash is a Gas Path Cleaning Wash. A water Wash os mainly used to clean the Compressor and you can do that with Motoring the engine with the Spray ring installed. The LIX wash plumbs into the compressor and the fuel Nozzle ring.
the Difference? One wil help Maintain Performance while the other? Can Improve engine Performance aside from making a damn mess.

Thanks for your replies.

the LIX wash system we used flushed all kinds of soot and Carbon out of the engine, It took a long time but it's now used to restore engine performance. It will restore proper Spray pattern to the Start Nozzles and clean the total Gas Path, I just wish I'd have invented it!!

a compressor wash and a LIX wash are two entirely different things A LIX wash is a Gas Path Cleaning Wash. A water Wash os mainly used to clean the Compressor and you can do that with Motoring the engine with the Spray ring installed. The LIX wash plumbs into the compressor and the fuel Nozzle ring.
the Difference? One wil help Maintain Performance while the other? Can Improve engine Performance aside from making a damn mess.

Thanks ftrfyrs51. As I said I am familiar with a regular engine wash (called also compressor wash to reduce EGT) but I am not familiar with LIX wash. I google it and I tried youtube and I didn't got any result. You said that a LIX wash is a gas path cleaning wash and it plumbs into the compressor and the fuel nozzle ring. I don't understand that and I don't understand how this cleaning will restore proper pattern spraying especially in modern engines: to my knowledge the fuel nozzle frontal surfaces and its center holes (primary and secondary fuel flow) are not facing the air/water/cleaning liquid flow in the combustor.
It will be very helpful if you give more information about this LIX wash.

Feedback appreciated.

aerotech777 wrote:

Thanks for your replies.

the LIX wash system we used flushed all kinds of soot and Carbon out of the engine, It took a long time but it's now used to restore engine performance. It will restore proper Spray pattern to the Start Nozzles and clean the total Gas Path, I just wish I'd have invented it!!

a compressor wash and a LIX wash are two entirely different things A LIX wash is a Gas Path Cleaning Wash. A water Wash os mainly used to clean the Compressor and you can do that with Motoring the engine with the Spray ring installed. The LIX wash plumbs into the compressor and the fuel Nozzle ring.
the Difference? One wil help Maintain Performance while the other? Can Improve engine Performance aside from making a damn mess.

Thanks ftrfyrs51. As I said I am familiar with a regular engine wash (called also compressor wash to reduce EGT) but I am not familiar with LIX wash. I google it and I tried youtube and I didn't got any result. You said that a LIX wash is a gas path cleaning wash and it plumbs into the compressor and the fuel nozzle ring. I don't understand that and I don't understand how this cleaning will restore proper pattern spraying especially in modern engines: to my knowledge the fuel nozzle frontal surfaces and its center holes (primary and secondary fuel flow) are not facing the air/water/cleaning liquid flow in the combustor.
It will be very helpful if you give more information about this LIX wash.

with aFeedback appreciated.

I'm retired now.. but the Gas path cleaner used in the LIX wash came in 55 Gallon Barrels and had a lot of plumbing to the intake and the Fuel Nozzle ring. United had a pretty good catchment system for the stuff at SFO that came out of the engines. I had information on it because My Crews had to perform them Periodically if we had an engine Going South with High Start Temps and Takeoff EGT margins limited. After I went to Maint. Control? I have NO Idea whether they continued the program as I was no longer a Line Foreman. (From 1999-2017) But I BET you could write someone at SFOEP.