Mec. fuel pump wear....

by EINAR-ARNE KLEIVEN in 912 / 914 Technical Questions 11 years ago

:angry:
My engine are about 2 years old, but never started, and never turned (been stored hot and dry)Are ready to start the engine, but because someone on this site had major problems with the pump, i released the fuelpump from the engine and took a look at the plunger/cam that is "powering" the pump..WTF; the plunger AND the cam are worn, with stripes and scratsches !!!(one can realy feel the scratches when a fingernail goes over it)
On this site for a long time ago: someone sugested to check this condition every 10hrs...If this is "normal" wear, you can call me a snappahead. But what shall one do? warranty out, and it is at your own risk. (really looking forward to that day someone make a engine that is acting like a car engine, just add oil and go...)

Re: Mec. fuel pump wear....

by Roger Lee » 11 years ago

Roger Lee

127 5.2k 4.78k

Hi EINAR-ARNE,

Sorry for your frustration and problem.
If the scratches are very minor and the plunger is flat across its surface then it may be okay to lube the plunger (copper anti seize) and use the pump. If the scratches are that minor they may disappear with a little time after rotation on the lobe. Scratches should have only occurred from a dry rotation and or contaminated oil. If the plunger is lopsided and or the scratches more severe then it needs replacement. Scratches and lopsided plungers are not the norm and you should not need to check them every 10 hrs.

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Report
Re: Mec. fuel pump wear....

by Roger Lee » 11 years ago

Roger Lee

127 5.2k 4.78k

Just an FYI,
It is like a motorcycle engine or car. They too have recalls and failures. Rotax like any engine MFG recommends that engines do not sit for long periods of time. This causes dry seals, dry bearings, dry gaskets and dry or cracked "O" rings. Once it sat so long then precautions should be taken before you rotate the prop even by hand or start the engine just like motorcycle and car MFG's recommend. If it sat this long then all metal parts that were lubed from the factory run before shipping became dry. The fuel pump plunger was most likely dry and would be a dry metal to metal scrape. When a new pump is installed or it has sat for years it is best to apply a little copper anti seize to the tip of the plunger before any prop rotation so it has a small amount of lube as the engine starts and the oil takes over the lube process. When leaving an engine sit for a couple of years then before start it should be checked for any applicable service bulletins before the first start.

All engines need maint. and to do them properly. Don't treat this engine like a Continental or Lycoming. Just like any engine it has its own procedures and they are all in the manuals. The number one cause for Rotax issues is failing to follow both of these.

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Report
Re: Mec. fuel pump wear....

by EINAR-ARNE KLEIVEN » 11 years ago

EINAR-ARNE KLEIVEN

2 3 0

Thanks

I was maybee too conserned before i released the pump. And when i discovered the scratshes, my feelings took overhand before my sense...The plunger and cam are just having minor stripes. So if it was on my gardening tracktor, i would not hasitate to use it..but when it is on my aircraft, i was hoping it was shiny as a mirror.
And when reading on this forum, i understand that even when the pump is wearing a lot, it is still functioning.(and some people/pilots say that the engine is running even without the pump...)

(The engine are mounted on my new Norwegian built STOL 701) So with this in mind, i will put the pump back on place lubricated, and use it. (since it is easy to remove, i will check it after some use !!)

Thanks again for a usefull forum :)
Einar-Arne Kleiven Norway

Report
Re: Mec. fuel pump wear....

by ERNEST BITTEN » 11 years ago

ERNEST BITTEN

7 37 78

Hi EINAR-ARNE,

Sorry for your frustration and problem.
If the scratches are very minor and the plunger is flat across its surface then it may be okay to lube the plunger (copper anti seize) and use the pump. If the scratches are that minor they may disappear with a little time after rotation on the lobe. Scratches should have only occurred from a dry rotation and or contaminated oil. If the plunger is lopsided and or the scratches more severe then it needs replacement. Scratches and lopsided plungers are not the norm and you should not need to check them every 10 hrs.

The ROTAX maint manual and parts manual don't show application of a lubricaant to the plunger (or maybe I missed it when I did my pump replacement?). They also didn't mentioned it at ROTAX school. Is this just good practice?

Report
Re: Mec. fuel pump wear....

by Roger Lee » 11 years ago

Roger Lee

127 5.2k 4.78k

Hi Ernie,

It should have been mentioned in Rotax school, but it would also depend on what level of class you were in, the instructor and or if a question arose. All metal to metal or rotating parts parts should have some lube prior to a start or hand rotation. It may be just a film of oil, or white grease or copper anti seize and the type of lube will depend on which area you need the lube on. Not every little thing is in the manual, all manuals are the same some place and that's why it pays to attend a Rotax class. Good common sense about its location and operation before a rotation may be helpful in knowing if it is advisable to pre-lube a part.

A good rule of thumb:
If it rides in an oiled environment then it probably needs pre-lubing.

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Report

You do not have permissions to reply to this topic.

Title	Category	Replies
One engine using too much fuel	912 / 914 Technical Questions	5
Low low fuel pressure and flow at high altitude	912 / 914 Technical Questions	18
Low low fuel pressure and flow at high altitude	912 / 914 Technical Questions	0
"High" fuel pressure alerts	915iS Technical Questions	1
Low fuel pressure	912 / 914 Technical Questions	7

Mec. fuel pump wear....

Recent Videos

Safety First!

ROTALK News

Prize Giveaway!

Log In/Out

Login