PA-18 engine failure

Want to share my experience with broken fuel pump:

A week ago I took off from a grass strip with my 95 SuperCub when the engine quit at about 200 ft. I could land straight ahead - no damage. I suspected vapor lock and let the engine run, which was still idling. Made a full power check to clear the fuel lines and took off again. This time I experienced some power loss, so I climbed away. Cruise was uneventful. In flight I tried different pitch attitudes with full power and realized that the engine failed each time after some time with high pitch on each tank. Nose down and the engine came in again after a few seconds. When I did the deadstick landing I surely pulled back the throttle without thinking about it, otherwise the engine would have recovered with full power again. Suspected fuel supply problems or the carburetor. When I disassembled the fuel pump I found the linkage from the diaphragm to the rod was corroded away, so the pump was dead and I only had gravity feed through the pump! The fuel had to go up to the front of the engine where the pump is sitting and through all the restrictions in the pump and the plumbing. So with high pitch attitudes there was no fuel supply to the carb.
Here is a link to a picture I made of the disassembled fuel pump:

Do you have a fuel injected C-90?

I have never seen a fuel pump on a cub engine.

Tim

I was wondering the same thing. Why fuel pump? Gravity works great for Cubs.

I was wondering too.
I don´t know this was an option to avoid vapors when it´s hot, it might help then but I don´t know. It is a C90-14F and it was installed in 1996 as there was no 12F available.
So your´s doesn´t have the engine driven pump at all?

fuel pump

747, That engine must have been out of a aircoupe or some other low wing plane I would get rid of the pump if possible and set the plane up with a Marvel Carb the way they were from the factory.

Dave

Here is a picture of my C90-12F when the fuel hose was off for the annual pressure test excuse my poor editing I have drawn the routing Direct from Gascolator to messers Marvel Schebler. Hope that helps! UKCN

It's important to use the carb indicated in the TC. For example, we put a carb on a C90 that had been used on a C90 in an Ercoupe. Worked fine on the Ercoupe. It did not work well on the PA-11. It would lose power long enough to get your attention before coming back to life, usually right after takeoff.

Why? While approved for a C90, it was set up for the C90 application on an Ercoupe, which has a different cowl configuration, etc. requiring a slightly different carb setup. So, check the TC for the -95 and put the Stromberg/Marvel Schebler on that is indicated in the TC.

Lindbergh's rules of flying win again, less is better, the more parts you have the more things you have that want to fail, K.I.S.S

Glenn

Over the years, I've owned 4 Cubs from 85hp to 180 hp. None had a fuel pump. The simpler the system the better, get the right carb and ditch the pump. Gravity never quits. Bill

While an Ercoupe (at least the 415C I used to fly) does have a fuel pump. It does NOT feed the carb.
The carb is gravity fed from the nose tank.
The fuel pump fills the nose tank drawing from the wing tanks and excess fuel overflows back into the wing tanks.
DaveG

Yep.. I shake my head every time I see a high wing carburated homebuilt come thru the shop sporting a fuel pump and a back up electric boost.. why why why..

"Hose removed for annual pressure test"? Man, I'm glad I'm not paying for an annual inspection over there! Jim

Doesn't the -14 use different engine mount bushings.

Looked it up and yes it is different. From the Type Certificate Data Sheet:
The C90-14 models incorporate Lord type engine mounts which are not interchangeable with C90-12 models
due to different machining of the engine mounting lugs on the engine crankcase.

Yes the 14F has Lord engine mounts.
JRussel: What means TC?

Type Certificate Data Sheet. Here: http://rgl.faa.gov/Regulatory_and_G...07594D9541211BDB862572090071FC6E?OpenDocument

The 1A2 TC covers that model airplane. In the first section, it describes both the engine model and carburetor type specified.

Anything else would have to be installed via an STC or Field Approval.

MTV

OK

STMAWR14
You might be right - or you might not!
Not everywhere you are a real man if you never slept beside a grizzly!
And many people know lots of things these real men don´t know, that´s for sure!

Yes - I don´t know the real difference between "Slick" and "Bendix". So what!? I am still learning and I am sure I will never know everything.
And I am living in another country, we have a different language and some of the english abbreviations I am not familiar with! And we might have some different regulations and wording here as I already learned!

BTW what means "fickin" mind?

Hey 747driver,
What did you decide on the fuel pump? Did you ever find out why you have it?

Bugs66

The pump is probably there because the engine was installed as a replacement some fourteen or so years ago. I found out this looking at the old logs. And I believe the pump was and is there as ag-pilot above stated that it´s probably out of a low wing airplane. I bought a remanufactured pump this week and installed it today, so the plane is in the air again. I will check with the mechanic guys here whether I can remove the pump, if yes I do and keep it simple. I only can do this under "supervision" and most probably there should be some paperwork done. And also the Cub should be legal and according the specifications of "our FAA" here, the LBA.

Hi, sorry to bring this back to life, but is there an STC yo mount the C-90 14F on the 18-95? Else, is there an STC yo mount any legal engine on the 18-95 other that 12F?
Regards,
JM