Fuel Leak - Pushrod Tube

[ttflyer]

Just curious if anyone has ever seen this (picture attached).  We replaced the fuel line from the spider valve to the injector and cleaned the pushrod tube.  This was after about 4 hours of flying after that.  So obviously didn't work...

Mechanic now wants to change the injector.  I would think a leaking injector would be more....  around the injector.  But what do I know?

edit: Not sure why the picture turned but this is the #2 cylinder...

[MikeOH]

It looks to me like there is staining around the injector. With engine off I’d go WOT and full rich with boost pump on. It seems like you’d see where the leak was. In my non-A&P opinion.

[Ragsf15e]

41 minutes ago, ttflyer said:

Just curious if anyone has ever seen this (picture attached).  We replaced the fuel line from the spider valve to the injector and cleaned the pushrod tube.  This was after about 4 hours of flying after that.  So obviously didn't work...

Mechanic now wants to change the injector.  I would think a leaking injector would be more....  around the injector.  But what do I know?

edit: Not sure why the picture turned but this is the #2 cylinder...

Id probably try removing, cleaning and reinstalling the injector first as it’s hard to “break” them.  Where’s the bleed hole positioned with the correct torque?

[EricJ]

That doesn't look like the right injector nozzle.   At least I've not seen one on a Lycoming IO-360 that looks like that.

This is an LW-18265 nozzle.

[ttflyer]

4 minutes ago, EricJ said:

That doesn't look like the right injector nozzle.   At least I've not seen one on a Lycoming IO-360 that looks like that.

This is an LW-18265 nozzle.

It's a GAMI injector...

[N201MKTurbo]

I know it is a GAMI injector, but they don’t matter in an IO-360. If you think it is the injector, swap it with another cylinder and see if the problem moves.

Some say the bleed hole position can do that, so you might check that.

[kortopates]

I know it is a GAMI injector, but they don’t matter in an IO-360. If you think it is the injector, swap it with another cylinder and see if the problem moves.
Some say the bleed hole position can do that, so you might check that.

They don’t matter on the vast majority of Io-360’s but somewhere near 10-15% of the fleet benefits from Gami’s.
Does your Rayjay still yield good mixture with stock injectors? The majority of Rayjay turbo STC’s i see don’t get good mixture within 0.5 GPH without them.


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[47U]

5 hours ago, ttflyer said:

dit: Not sure why the picture turned but this is the #2 cylinder...

 

[N201MKTurbo]

15 minutes ago, kortopates said:

They don’t matter on the vast majority of Io-360’s but somewhere near 10-15% of the fleet benefits from Gami’s.
Does your Rayjay still yield good mixture with stock injectors? The majority of Rayjay turbo STC’s i see don’t get good mixture within 0.5 GPH without them.


Sent from my iPhone using Tapatalk

My GAMI spread is about 0.2 GPH. At 28in I can run it down to about 7 GPH. It never gets rough, it just quits making power.

My intake path has no bends in it to upset the airflow. From the turbo it goes through the intercooler and then makes a gentle sweep to the servo. I think the intercooler removes any turbulence from the flow.

[0TreeLemur]

36 minutes ago, N201MKTurbo said:

removes any turbulence

Aha!  Finally something on MS that I know about!   Your intercooler creates a boatload of turbulence.   That turbulence injects a bunch of small scale kinetic (rotational) energy in the flow, which helps promote uniform flow throughout the induction system.

[Ragsf15e]

47 minutes ago, 47U said:

 

The bleed hole is opposite the letter stamped on the flat.  I can just make out the letter, so bleed hole is pointing backward towards cylinder 4…

[hubcap]

1 hour ago, 0TreeLemur said:

Aha!  Finally something on MS that I know about!   Your intercooler creates a boatload of turbulence.   That turbulence injects a bunch of small scale kinetic (rotational) energy in the flow, which helps promote uniform flow throughout the induction system.

Does this mean an engine with an intercooler should theoretically run smoother?

[N201MKTurbo]

3 hours ago, 0TreeLemur said:

Aha!  Finally something on MS that I know about!   Your intercooler creates a boatload of turbulence.   That turbulence injects a bunch of small scale kinetic (rotational) energy in the flow, which helps promote uniform flow throughout the induction system.

Sure, on a micro scale, I’m sure it does, but on a macro scale, it removes any swirl or other uneven flow. 

[0TreeLemur]

40 minutes ago, N201MKTurbo said:

Sure, on a micro scale, I’m sure it does, but on a macro scale, it removes any swirl or other uneven flow. 

Yes- helps promote uniform flow

[N201MKTurbo]

3 hours ago, hubcap said:

Does this mean an engine with an intercooler should theoretically run smoother?

Maybe.

[Ragsf15e]

On 9/14/2023 at 10:01 AM, ttflyer said:

Just curious if anyone has ever seen this (picture attached).  We replaced the fuel line from the spider valve to the injector and cleaned the pushrod tube.  This was after about 4 hours of flying after that.  So obviously didn't work...

Mechanic now wants to change the injector.  I would think a leaking injector would be more....  around the injector.  But what do I know?

edit: Not sure why the picture turned but this is the #2 cylinder...

I’m not gonna say it’s causing the issue, but I’d tighten the injector to make the bleed hole face up which puts the letter on the flat facing down.  That’s how lyc says it should be anyway.  Usually doesn’t make a huge difference, but Here’s my theory… pointing backwards, it’s subject to lower pressure as the airflow goes around it and under certain conditions, some little fuel is sucked out and sprayed up there.  I didn’t say it was a great theory, but what does it cost to rotate the injector ~90 degrees?

[Yetti]

you have fuel staining up from a possible source.  Liquid usually does not flow up.  So it seems like it is under pressure and getting shot up there.   I would check to see if the fuel distribution line was tight.   Also it is really easy to fubar the threads on the fuel distribution line.   There is also a AD on the fuel lines.

[Ragsf15e]

53 minutes ago, Yetti said:

you have fuel staining up from a possible source.  Liquid usually does not flow up.  So it seems like it is under pressure and getting shot up there.   I would check to see if the fuel distribution line was tight.   Also it is really easy to fubar the threads on the fuel distribution line.   There is also a AD on the fuel lines.

I agree with that, but it could also be a little dribble grabbed by the crazy airflow through there.  The airflow is strong and hard to predict.  Either way, be care With the threads.  There’s lyc guidelines on tightening the injectors and getting the bleed aligned properly.

[Yetti]

34 minutes ago, Ragsf15e said:

I agree with that, but it could also be a little dribble grabbed by the crazy airflow through there.  The airflow is strong and hard to predict.  Either way, be care With the threads.  There’s lyc guidelines on tightening the injectors and getting the bleed aligned properly.

Unless the camera inverted the image, this is on the #1 cylinder which would be up front.   The airflow should be across from #1 to #3 and down the fins of #1 and #3 to the low air pressure below.   So the stain should be on the backside of the tube.   That's why I think this is a high pressure leak from the flow divider running down the bottom of the injector line and dripping on the push rod tube.   or coming out of the top of the fuel line nut.

[N201MKTurbo]

24 minutes ago, Yetti said:

Unless the camera inverted the image, this is on the #1 cylinder which would be up front.   The airflow should be across from #1 to #3 and down the fins of #1 and #3 to the low air pressure below.   So the stain should be on the backside of the tube.   That's why I think this is a high pressure leak from the flow divider running down the bottom of the injector line and dripping on the push rod tube.   or coming out of the top of the fuel line nut.

That is definitely #2. #1 has the injector at the back of the cylinder. #2 is the pilot side front cylinder.

[N201MKTurbo]

On 9/14/2023 at 10:01 AM, ttflyer said:

Just curious if anyone has ever seen this (picture attached).  We replaced the fuel line from the spider valve to the injector and cleaned the pushrod tube.  This was after about 4 hours of flying after that.  So obviously didn't work...

Mechanic now wants to change the injector.  I would think a leaking injector would be more....  around the injector.  But what do I know?

edit: Not sure why the picture turned but this is the #2 cylinder...

Have you contacted GAMI about this?

[ttflyer]

2 hours ago, N201MKTurbo said:

Have you contacted GAMI about this?

I did!  Probably should have called them before posting.  Basically they said it's not uncommon for Mooneys.  Something about weird airflow on the M20J right there by the #2 cylinder.  Said it probably happens at TOD when you push over and pick up speed.  He said keep an eye on it but I'm not going to worry too much about it. 

They are sending another injector for an unrelated reason.  Might try and put it there first just to see what happens...  We've already changed the fuel line from the spider valve so not much else it could be...

[N201MKTurbo]

1 hour ago, 47U said:

I completely missed that the image was not only 90 degrees out, but also reversed.  I think this is now correct… yes?

Nope, flip it left to right. It was correct before.

[N201MKTurbo]

[47U]

1 hour ago, N201MKTurbo said:

Nope, flip it left to right. It was correct before.

Now I’ve embarrassed myself… I’ll just delete the previous mistake and let sleeping dogs lie… 

Thank you.