Replaced hose that runs from oil filler to air-oil separator

[LANCECASPER]

The once yellow hose that runs from the the oil filler neck back to the air oil separator was not flexible anymore especially on the engine side of the baffle and there was a little sludge in there restricting flow from the oil filler to the air oil separator, so I decided to replaced it.

The product Mooney used is Tygon F-4040-A (1" OD, 3/4" ID) (AAG00053). McMaster-Carr had it in 5 foot lengths. This gave me enough to replace the piece that runs from the rear of the engine to cool the backup alternator (also pictured above). Easy to do, looks better, hopefully keeping it clear and keeping the sludge out keeps pressure down which has contributed to coking on the exhaust on these engines. It's cheap enough I'll probably do it on every annual or at least every other year.

 

 

[Schllc]

There are two SB’s which were to address the coming issue, one is regular inspections , the other is a welded modification of the exhaust SB m20-319.

this one eliminates the need for recurring inspections. 

[carusoam]

Interesting…

Tygon F4040 is a flexible, plasticized PVC tube specific for handling oil…

the plasticizer bleeds out as it ages… it turns brown and gets stiffer…

 

PP thoughts only, not a mechanic…

best regards,

-a- 

[LANCECASPER]

9 hours ago, Schllc said:

There are two SB’s which were to address the coming issue, one is regular inspections , the other is a welded modification of the exhaust SB m20-319.

this one eliminates the need for recurring inspections. 

That inspection is for the lower breather hose and the left tail pipe. What I did is just the upper hose that goes to the air-oil separator, I have the lower TCM hose backordered since it looks a little brittle. When I inspected the connection of that hose to the exhaust with a borescope, so far it's clear.

[Schllc]

13 hours ago, LANCECASPER said:

That inspection is for the lower breather hose and the left tail pipe. What I did is just the upper hose that goes to the air-oil separator, I have the lower TCM hose backordered since it looks a little brittle. When I inspected the connection of that hose to the exhaust with a borescope, so far it's clear.

I understand, the coking issue was caused by the lower breather pipe becoming occluded, not the top pipe.  
at least that was how it was explained to me. 

[LANCECASPER]

29 minutes ago, Schllc said:

I understand, the coking issue was caused by the lower breather pipe becoming occluded, not the top pipe.  
at least that was how it was explained to me. 

The breather hose at the bottom of the air oil separator goes to the lower breather pipe. If the top hose which goes from the oil filler tube  into the top of the air oil separator gets clogged then it raises cylinders pressure which affects exhaust, so this can also have an effect on the coking.
I am anxious to get the back-ordered lower hose since that rides so close to the turbo charger it gets very hot and brittle and should be changed often. The lower hose which is all the way from the air oil separator is only $27 so it’s not a big expense, but worth doing every year or two.

[LANCECASPER]

On 2/16/2022 at 10:01 PM, carusoam said:

Interesting…

Tygon F4040 is a flexible, plasticized PVC tube specific for handling oil…

the plasticizer bleeds out as it ages… it turns brown and gets stiffer…running to the ar

 

PP thoughts only, not a mechanic…

best regards,

-a- 

It definitely darkens and gets stiffer from heat and age and probably outgassing,  but most of the dark brown is from oil running to the air oil separator. This picture is after i had removed it and rinsed it with mineral spirits. Some sludge came out when I ran mineral spirits through it, but it wasn’t completely blocked.

[LANCECASPER]

10 hours ago, GEE-BEE AEROPRODUCTS said:

Fyi , love your hack unfinished ducts.

Exactly the way it was delivered from Mooney.