Oil Pressure Drop on Take-off - SOLVED!

Re: Oil Pressure Drop on Take-off - SOLVED!

by Bill Hertzel » 6 years ago

Bill Hertzel

13 1.95k 8k

... Are we talking the ground wire on the back of the Gauge? Or a wire on the sender?

The answer is YES!

Both the Gauge and the Sender have ground connections. And they both need to be good.
The sender may be grounded in the engine compartment or, preferably, it may have the ground wire connected at the gauge.

---

Bill Hertzel
Rotax 912is
North Ridgeville, OH, USA
Clicking the "Thank You" is Always Appreciated by Everyone.

Re: Oil Pressure Drop on Take-off - SOLVED!

by John Fleming » 6 years ago

John Fleming

16 99 119

OK Thanks Bill. I will check it out.

Re: Oil Pressure Drop on Take-off - SOLVED!

by Aaron » 6 years ago

Aaron

14 129 67

Had this same issue a few months ago.
The guys here help me solve it.

The low oil pressure on takeoff was due to a 5 in diameter bend that the last mechanic put in when he did the 5 year rubber. Previous owner Installed a thermostat which made a few spots pretty tight.

I recall a 8 inch diameter bent the minimum. The low on takeoff is probably something like that.

If your gauges are good, think about the mushroom style oil regulator, new spring and bolt for the low pressure other than takeoff.

Re: Oil Pressure Drop on Take-off - SOLVED!

by John Fleming » 6 years ago

John Fleming

16 99 119

That’s interesting as it’s not long had the rubber replacement. Do you know where in the system?

I will trace all of the lines and check it out.

Cheers
John

Re: Oil Pressure Drop on Take-off - SOLVED!

by John Fleming » 6 years ago

John Fleming

16 99 119

So this weekend I went to the airfield to do some work on the plane, and try and get to the bottom of the oil issue.

I checked all terminals and reseated them etc... still the same.

Here is what I found and a short video.

On cold start oil pressure hits about 80PSI and then when warmed up, and it drops to what looks to be about 40PSI.

Then when advanced to 3000RPM, the pressure drops. At take off (5500+) it drops even lower.

I might look to swap out the sensor first, and see what happens.

See below.

https://www.dropbox.com/s/5y57a6ny1rrsfsr/IMG_5039.m4v?dl=0

Cheers
John