Fuel Divider Spider

[Roger M]

I just purchased 1996 M20M with recently overhauled Lycoming 540.  When advancing the throttle past idle, fuel sprays out of this uncapped port.

Do I need to cap it?

What do I need to do to correct this issue?

[Guest]

8 minutes ago, Roger M said:

I just purchased 1996 M20M with recently overhauled Lycoming 540.  When advancing the throttle past idle, fuel sprays out of this uncapped port.

Do I need to cap it?

What do I need to do to correct this issue?

No fuel should be leaking/spraying out anywhere.  A cap should be installed before flight.  In some installations, that fitting is connected to a fuel flow gauge.

[PT20J]

To amplify what @M20Doc said, some fuel flow gauges actually measure metered fuel pressure (which is proportional to fuel flow) and connect to that port. If you look closely at the flow divider case, that port is labelled GAGE. If not used, the hose fitting should be removed and replaced with a plug.

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[Fly Boomer]

1 hour ago, Roger M said:

Do I need to cap it?

As @PT20J pointed out:  "If not used, the hose fitting should be removed and replaced with a plug.".  Much better than capping the fitting that's already there.

[Yetti]

I think my fuel pressure line comes off the fuel servo,   Maybe comes off divider, can't remember.

[PT20J]

9 minutes ago, Yetti said:

I think my fuel pressure line comes off the fuel servo,   Maybe comes off divider, can't remember.

The fuel PRESSURE line comes off the servo near the inlet. The GAGE line on the flow divider is for a pressure type fuel FLOW gauge. Most Mooneys use an actual fuel flow transducer in the fuel line between the pump and the servo for fuel flow.

[OR75]

I would not fly that plane with fuel spraying out in the engine compartment. Outcome cannot be great  and those things typically don’t fix themselves 

[Yetti]

3 minutes ago, PT20J said:

The fuel PRESSURE line comes off the servo near the inlet. The GAGE line on the flow divider is for a pressure type fuel FLOW gauge. Most Mooneys use an actual fuel flow transducer in the fuel line between the pump and the servo for fuel flow.

Nope the 75 F only had a Fuel pressure gauge.   I think the Js started with the fuel flow gauges.

[Rmnpilot]

As others have stated, that port should be capped.  Here is mine for a 1994 Bravo.   Just had my fuel servo overhauled so had taken this photo recently 

[Guest]

2 hours ago, Fly Boomer said:

As @PT20J pointed out:  "If not used, the hose fitting should be removed and replaced with a plug.".  Much better than capping the fitting that's already there.

A cap would be better than ruining the flow divider if the fitting is seized in place.

[Guest]

53 minutes ago, Yetti said:

Nope the 75 F only had a Fuel pressure gauge.   I think the Js started with the fuel flow gauges.

Mooney’s in my experience used fuel pressure measured at the carburetor finger screen or the fuel servo finger screen.  Flow was measured with a flow transducer, FT 101 was a common factory installation.

[Guest]

Bravo fuel pressure transducer installation, lower right side of the engine referenced to compressor air pressure.

[A64Pilot]

To be clear, most aircraft that had fuel flow gauges that often were combo gauges MP / FF were actually pressure gauges, but marked in GPH, they inferred flow from pressure.

My Maule had such a gauge and when I installed an MVP-50 I put a cap on that fitting, the pressure there is very low, I forget what it is but it’s not enough to bother a cap.

I think even at full throttle it’s less than 20 PSI

I know the port marked gauge has a restricted orifice so all the fuel won’t dump out if the line breaks and to keep the leak small. That restricted orifice may be in the fitting

[carusoam]

@Roger M

 

Yikes!

You have some really good feed back with pics supporting them….

One question…

How did you buy a plane with this ‘flaming disaster’ awaiting you?

When did you find the fuel spraying?

There are sooo many red hot parts on a turbo Mooney… having fuel leaking around inside the cowling, could be disastrous ….

A Good Pre-purchase inspection goes a long way…

A good post purchase inspection may be a good alternative…. Something to seriously consider….

Fuel leaks under the cowl of any airplane is not normal…

Somebody had to know something about this plane to have it get in that condition… check it’s logs to see what is recorded…

Expect there is a restrictor still in place, as mentioned above… or the fuel would have been streaming out that size hole….

Talk with the people who installed the engine… it seems they didn’t quite finish the installation…. 

Good luck with the next steps…

PP thoughts only, not a mechanic…

Best regards,

-a-

[LANCECASPER]

21 hours ago, Roger M said:

I just purchased 1996 M20M with recently overhauled Lycoming 540.  When advancing the throttle past idle, fuel sprays out of this uncapped port.

Do I need to cap it?

What do I need to do to correct this issue?

What engine monitor do you have on this airplane?

Was it on there when you bought it (check the logs and see when it was installed) or has it been changed out recently? 

My guess is that when they went from the factory gauges to the JPI, EI or Garmin that they are getting the fuel pressure reading from another area and didn't complete the job of capping this off.

[Yetti]

2 hours ago, LANCECASPER said:

What engine monitor do you have on this airplane?

Was it on there when you bought it (check the logs and see when it was installed) or has it been changed out recently? 

My guess is that when they went from the factory gauges to the JPI, EI or Garmin that they are getting the fuel pressure reading from another area and didn't complete the job of capping this off.

That was my guess that someone went to the spinning fuel flow sensor over by the pilots feet and forgot to cap this.   Probably should have shown up in a fuel line AD inspection to a knowledgeable mechanic.

[A64Pilot]

4 hours ago, LANCECASPER said:

What engine monitor do you have on this airplane?

Was it on there when you bought it (check the logs and see when it was installed) or has it been changed out recently? 

My guess is that when they went from the factory gauges to the JPI, EI or Garmin that they are getting the fuel pressure reading from another area and didn't complete the job of capping this off.

That fitting isn’t used for fuel pressure as it varies with throttle position, it’s used for the old type of fuel flow gauges, unless his aircraft had one of those which is doubtful then the cap wasn’t moved over or was left off during the overhaul, which I think more likely.

I don’t think any 6 cyl Mooney ever had the old style, think Bonanza fuel flow gauge did they?

In other words I don’t think that fitting is ever used on a Mooney with a 540.

That means it’s likely whoever did the engine installation is at fault, and I believe it’s a serious mistake, whatever that’s worth, they should at leads be told about it so they don’t do it again.

[LANCECASPER]

21 minutes ago, A64Pilot said:

That fitting isn’t used for fuel pressure as it varies with throttle position, it’s used for the old type of fuel flow gauges, unless his aircraft had one of those which is doubtful then the cap wasn’t moved over or was left off during the overhaul, which I think more likely.

I don’t think any 6 cyl Mooney ever had the old style, think Bonanza fuel flow gauge did they?

In other words I don’t think that fitting is ever used on a Mooney with a 540.

That means it’s likely whoever did the engine installation is at fault, and I believe it’s a serious mistake, whatever that’s worth, they should at leads be told about it so they don’t do it again.

This is what the panel looked like when it was for sale in 2012 (https://www.aircraft.com/aircraft/1172923/n9154n-1997-mooney-m20m-bravo) and it shows a Shadin Mini-Flo on the panel just above the KAS297B Altitude Pre-Select. Not sure if they would have come off of this fitting or not.

[Roger M]

Thanks for all who responded.  I do appreciate it.

[A64Pilot]

5 hours ago, LANCECASPER said:

This is what the panel looked like when it was for sale in 2012 (https://www.aircraft.com/aircraft/1172923/n9154n-1997-mooney-m20m-bravo) and it shows a Shadin Mini-Flo on the panel just above the KAS297B Altitude Pre-Select. Not sure if they would have come off of this fitting or not.

The Shadin measures fuel flow, not pressure so it would not have come off this fitting. 

The fuel flow gauges that use that fitting are pressure gauges, but the marking is in GPH instead of PSI.

I don’t think any Mooney with a 540 uses that fitting, but I am no Mooney expert, so the engine installer screwed up, and obviously didn’t even leak check his installation is my belief.

 That’s so unbelievable it has me thinking someone must have removed it later, but why would anyone remove that cap? Maybe the cap was left loose?

[Guest]

54 minutes ago, A64Pilot said:

The Shadin measures fuel flow, not pressure so it would not have come off this fitting. 

The fuel flow gauges that use that fitting are pressure gauges, but the marking is in GPH instead of PSI.

I don’t think any Mooney with a 540 uses that fitting, but I am no Mooney expert, so the engine installer screwed up, and obviously didn’t even leak check his installation is my belief.

 That’s so unbelievable it has me thinking someone must have removed it later, but why would anyone remove that cap? Maybe the cap was left loose?

Or just maybe the cap has fallen off and is laying between the cylinders on the baffle?

[hais]

Echoing what @carusoam said. You should have a thorough inspection. That is a big miss, so begs the question, what else was missed? 

[A64Pilot]

14 minutes ago, M20Doc said:

Or just maybe the cap has fallen off and is laying between the cylinders on the baffle?

maybe, but it would have to have been leaking for quite awhile, but if it fell off, it’s likely still there. I could have probably filled a small tool box with all the tools I’ve found laying in between the cylinders, seems things hide there well.

[Yetti]

In other news, your MPG should increase slightly since you are not dumping fuel overboard.

[A64Pilot]

3 hours ago, Yetti said:

In other news, your MPG should increase slightly since you are not dumping fuel overboard.

Surely he wasn’t flying like that? If so then that fitting must have a restricted orifice or the engine would quit, fuel would come out of an open fitting like a fire hose.

Still The leak wouldn’t have been small, really lucky he didn’t become a flaming fireball.