Today's Message Index:
----------------------
1. 06:58 AM - Fuel pressure decline (saolesen)
2. 07:22 AM - Re: Fuel pressure decline (Kelly McMullen)
3. 07:24 AM - Re: Fuel pressure decline (Kearney)
4. 07:30 AM - Re: Fuel pressure decline (Tim Olson)
5. 07:44 AM - Re: Fuel pressure decline (Phil Perry)
6. 08:07 AM - Re: Fuel pressure decline (Dan Masys)
7. 08:23 AM - Re: Fuel pressure decline (Kearney)
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Fuel pressure decline |
My fuel pressure has been declining over the past 30 hours and on my last flight
it was in the low 20s and even dipped into the high teens. With the electric
pump is on the pressure returns to the normal level, so I think the sender is
ok. The sender is a Kavlico 150 psi model that was new when I replaced my panel
over the winter. The engine has 1000 hours on it since new.
I dont know how fuel pumps fail or how to troubleshoot fuel pump problems, so I
was hoping some one on the list can enlighten me on what I need to to do. Are
there other things that should be looked at besides the fuel pump? Are dirty
fuel screens a possible source of declining pressure? Rebuilt pumps are not
hugely expensive at about $260 from ACS, but I dont want to do the put in new
parts until it works method of trouble shooting.
Any help would be appreciated.
Thank you.
Sheldon Olesen
RV-10 N475PV 1003 hrs
Sent from my iPad
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Fuel pressure decline |
Mechanical pumps have diaphragms that do eventually fail. First sign is
leaking out the fuel drain from the pump. If your fuel pressure take-off is
at the fuel servo, the inlet screen to the servo could be partially
plugged. However, not too likely as you get normal pressure with boost
pump. Same with the filter in the tunnel. So I would look at the fuel pump
drain at the rear bottom of cowl. Don't confuse with air filter or sniffle
valve drain from the intake manifold. If it is wet after shut down, pump
may have a problem. Keep in mind that the fuel servo is designed to have a
minimum inlet pressure of 14 psi.
Kelly
On Mon, Aug 16, 2021 at 7:03 AM saolesen <saolesen@sirentel.net> wrote:
>
> My fuel pressure has been declining over the past 30 hours and on my last
> flight it was in the low 20=99s and even dipped into the high teens
. With
> the electric pump is on the pressure returns to the normal level, so I
> think the sender is ok. The sender is a Kavlico 150 psi model that was n
ew
> when I replaced my panel over the winter. The engine has 1000 hours on i
t
> since new.
>
> I don=99t know how fuel pumps fail or how to troubleshoot fuel pump
> problems, so I was hoping some one on the list can enlighten me on what I
> need to to do. Are there other things that should be looked at besides t
he
> fuel pump? Are dirty fuel screens a possible source of declining
> pressure? Rebuilt pumps are not hugely expensive at about $260 from ACS,
> but I don=99t want to do the =9Cput in new parts until it wor
ks method=9D of
> trouble shooting.
>
> Any help would be appreciated.
> Thank you.
>
> Sheldon Olesen
> RV-10 N475PV 1003 hrs
>
> Sent from my iPad
>
===========
===========
===========
===========
===========
>
>
Message 3
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Fuel pressure decline |
Steven
Check / replace your fuel screens and filters first. Do a static run up before
the service and see if there is a change.
Cheers
Les
Sent from my iPhone
> On Aug 16, 2021, at 8:19 AM, saolesen <saolesen@sirentel.net> wrote:
>
>
> My fuel pressure has been declining over the past 30 hours and on my last flight
it was in the low 20s and even dipped into the high teens. With the electric
pump is on the pressure returns to the normal level, so I think the sender
is ok. The sender is a Kavlico 150 psi model that was new when I replaced my
panel over the winter. The engine has 1000 hours on it since new.
>
> I dont know how fuel pumps fail or how to troubleshoot fuel pump problems, so
I was hoping some one on the list can enlighten me on what I need to to do.
Are there other things that should be looked at besides the fuel pump? Are dirty
fuel screens a possible source of declining pressure? Rebuilt pumps are not
hugely expensive at about $260 from ACS, but I dont want to do the put in new
parts until it works method of trouble shooting.
>
> Any help would be appreciated.
> Thank you.
>
> Sheldon Olesen
> RV-10 N475PV 1003 hrs
>
> Sent from my iPad
>
>
>
>
Message 4
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Fuel pressure decline |
Hi Sheldon,
Have you looked at the mechanical fuel pump plastic hose that leaks the
fuel out safely
if there is a diaphragm issue? Maybe you would notice if there were any
blue fuel
stains on it to show it was leaking. I don't have any good detail on
troubleshooting
such issues to pass on, but certainly my steps would include looking for
signs of fuel
leakage, checking my fuel line connections for tightness and leakage, and
checking the fuel screen by the fuel pump. Also it would be helpful to
see if the
problem happens on only one or both tanks. But beyond that, I think
if everything
else checked out, I'd just throw a new pump at it. If your problem goes
away, you
then know, and, you can open up the old one and see what caused it.
Tim
On 8/16/2021 8:58 AM, saolesen wrote:
>
> My fuel pressure has been declining over the past 30 hours and on my last flight
it was in the low 20s and even dipped into the high teens. With the electric
pump is on the pressure returns to the normal level, so I think the sender
is ok. The sender is a Kavlico 150 psi model that was new when I replaced my
panel over the winter. The engine has 1000 hours on it since new.
>
> I dont know how fuel pumps fail or how to troubleshoot fuel pump problems, so
I was hoping some one on the list can enlighten me on what I need to to do.
Are there other things that should be looked at besides the fuel pump? Are dirty
fuel screens a possible source of declining pressure? Rebuilt pumps are not
hugely expensive at about $260 from ACS, but I dont want to do the put in new
parts until it works method of trouble shooting.
>
> Any help would be appreciated.
> Thank you.
>
> Sheldon Olesen
> RV-10 N475PV 1003 hrs
>
Message 5
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Fuel pressure decline |
In addition to the diaphragm and screens previously discussed, two other sou
rces would be:
1) A small leak before the pump where air is allowed to be sucked in. A h
ealthy boost pump would be capable of overcoming this leak and give you norm
al pressure indications.
2) Here we are in the heat of the summer and it=99s odd that you
=99ve chosen to complain about it in mid-August. I=99d consider heat
sources such as exhaust pipes, tunnel temps, etc to my list of items to con
sider. Perhaps some hoses or heat shields have changed or shifted recently.
Heat will cause vapor lock and result in low/fluctuating fuel pressures.
Phil
Sent from my iPad
> On Aug 16, 2021, at 9:26 AM, Kelly McMullen <apilot2@gmail.com> wrote:
> =EF=BB
> Mechanical pumps have diaphragms that do eventually fail. First sign is le
aking out the fuel drain from the pump. If your fuel pressure take-off is at
the fuel servo, the inlet screen to the servo could be partially plugged. H
owever, not too likely as you get normal pressure with boost pump. Same with
the filter in the tunnel. So I would look at the fuel pump drain at the rea
r bottom of cowl. Don't confuse with air filter or sniffle valve drain from t
he intake manifold. If it is wet after shut down, pump may have a problem. K
eep in mind that the fuel servo is designed to have a minimum inlet pressure
of 14 psi.
> Kelly
>
>
>
> On Mon, Aug 16, 2021 at 7:03 AM saolesen <saolesen@sirentel.net> wrote:
>>
>> My fuel pressure has been declining over the past 30 hours and on my last
flight it was in the low 20=99s and even dipped into the high teens.
With the electric pump is on the pressure returns to the normal level, so I
think the sender is ok. The sender is a Kavlico 150 psi model that was new
when I replaced my panel over the winter. The engine has 1000 hours on it s
ince new.
>>
>> I don=99t know how fuel pumps fail or how to troubleshoot fuel pump
problems, so I was hoping some one on the list can enlighten me on what I n
eed to to do. Are there other things that should be looked at besides the f
uel pump? Are dirty fuel screens a possible source of declining pressure? R
ebuilt pumps are not hugely expensive at about $260 from ACS, but I don
=99t want to do the =9Cput in new parts until it works method=9D
of trouble shooting.
>>
>> Any help would be appreciated.
>> Thank you.
>>
>> Sheldon Olesen
>> RV-10 N475PV 1003 hrs
>>
>> Sent from my iPad
>>
>> ==========
>> -List" rel="noreferrer" target="_blank">http://www.matronics.com/Navi
gator?RV10-List
>> ==========
>> FORUMS -
>> eferrer" target="_blank">http://forums.matronics.com
>> ==========
>> WIKI -
>> errer" target="_blank">http://wiki.matronics.com
>> ==========
>> b Site -
>> -Matt Dralle, List Admin.
>> rel="noreferrer" target="_blank">http://www.matronics.com/contributio
n
>> ==========
Message 6
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Fuel pressure decline |
Had a similar story beginning at about 1100 hours TTSN on the IO-540 in my
-10. Fuel pressures would drift down during prolonged climbs and fall
below 15 psi which was my alarm threshold. Responded immediately to
turning on the electric boost pump but that pushed fuel flows very high and
the engine would get a little rough.
So first, I replaced the fuel pressure sender. No joy - same problem.
Then replaced the engine driven fuel pump. End of problem.
Never saw a leak or overflow evidence in the drain tube. Seemed to be just
a tired pump or something.
-Dan Masys
N104LD 14 years and 1235 ttsn
On Mon, Aug 16, 2021 at 7:35 AM Tim Olson <Tim@myrv10.com> wrote:
>
> Hi Sheldon,
>
> Have you looked at the mechanical fuel pump plastic hose that leaks the
> fuel out safely
> if there is a diaphragm issue? Maybe you would notice if there were any
> blue fuel
> stains on it to show it was leaking. I don't have any good detail on
> troubleshooting
> such issues to pass on, but certainly my steps would include looking for
> signs of fuel
> leakage, checking my fuel line connections for tightness and leakage, and
> checking the fuel screen by the fuel pump. Also it would be helpful to
> see if the
> problem happens on only one or both tanks. But beyond that, I think
> if everything
> else checked out, I'd just throw a new pump at it. If your problem goes
> away, you
> then know, and, you can open up the old one and see what caused it.
>
> Tim
>
> On 8/16/2021 8:58 AM, saolesen wrote:
> >
> > My fuel pressure has been declining over the past 30 hours and on my
> last flight it was in the low 20=99s and even dipped into the high
teens.
> With the electric pump is on the pressure returns to the normal level, so
I
> think the sender is ok. The sender is a Kavlico 150 psi model that was n
ew
> when I replaced my panel over the winter. The engine has 1000 hours on i
t
> since new.
> >
> > I don=99t know how fuel pumps fail or how to troubleshoot fuel pu
mp
> problems, so I was hoping some one on the list can enlighten me on what I
> need to to do. Are there other things that should be looked at besides t
he
> fuel pump? Are dirty fuel screens a possible source of declining
> pressure? Rebuilt pumps are not hugely expensive at about $260 from ACS,
> but I don=99t want to do the =9Cput in new parts until it wor
ks method=9D of
> trouble shooting.
> >
> > Any help would be appreciated.
> > Thank you.
> >
> > Sheldon Olesen
> > RV-10 N475PV 1003 hrs
> >
>
===========
===========
===========
===========
===========
>
>
Message 7
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Fuel pressure decline |
Steven
All the ideas posted are great. My overarching recommendation would be to do the
simple / easy / low cost things first and work your way up on that scale.
I had a similar issue many months ago - it was a contaminated filter after I got
a load of bad gas.
Cheers
Les
Sent from my iPhone
> On Aug 16, 2021, at 8:32 AM, Kearney <kearney@shaw.ca> wrote:
>
>
> Steven
>
> Check / replace your fuel screens and filters first. Do a static run up before
the service and see if there is a change.
>
> Cheers
>
> Les
>
> Sent from my iPhone
>
>> On Aug 16, 2021, at 8:19 AM, saolesen <saolesen@sirentel.net> wrote:
>>
>>
>> My fuel pressure has been declining over the past 30 hours and on my last flight
it was in the low 20s and even dipped into the high teens. With the electric
pump is on the pressure returns to the normal level, so I think the sender
is ok. The sender is a Kavlico 150 psi model that was new when I replaced my
panel over the winter. The engine has 1000 hours on it since new.
>>
>> I dont know how fuel pumps fail or how to troubleshoot fuel pump problems, so
I was hoping some one on the list can enlighten me on what I need to to do.
Are there other things that should be looked at besides the fuel pump? Are dirty
fuel screens a possible source of declining pressure? Rebuilt pumps are
not hugely expensive at about $260 from ACS, but I dont want to do the put in
new parts until it works method of trouble shooting.
>>
>> Any help would be appreciated.
>> Thank you.
>>
>> Sheldon Olesen
>> RV-10 N475PV 1003 hrs
>>
>> Sent from my iPad
>>
>>
>>
>>
>
>
>
>
>
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|