Oil Pressure Sender

[builderflyer]

I installed the Kavlico pressure transducer (P255-150G-E4A) directly on the 3300 engine today. Using the Dynon Skyview, it was necessary to run two additional wires from the engine module to the transducer, a 5 volt wire and a ground wire. The original signal wire that was previously connected to the VDO type sensor was reused on the Kavlico. The Skyview was then reprogrammed to accept this most current Kavlico transducer and upon running the engine, the oil pressure reading was consistent with what had been observed with the previous sensor.

I had intended to install the Swift sender as some others had done successfully. But when Paul learned from AS & S that the burst pressure rating was as low as it is, and when David A reminded me of the possibility of high oil pressure spikes, the Kavlico appeared to be the safer alternative with its 2,000 psi burst pressure rating.

Art,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,Jabiru 3300 #261

[Friesen5]

FYI - I received a reply from GRT, who advised to use a scale factor of 63 and an offset of 25. The offset may be adjusted up or down in increments of 2 (always an odd number) to zero out the reading at zero pressure.

This is with the Swift 100 psi sender.

I haven’t installed it yet due to the severe winter weather we are experiencing in Canada.

Mervin Friesen
Sonex 122

[lpaaruule]

I flew for an hour today with the new Kavlico pressure transducer (P255-150G-E4A). It performed well; no high pressure spikes. However, my oil pressure fluctuates from 30 - 60psi with while being around 40psi 95% of the time. Occasionally it will drop to 25 for a split second. I didn't put in an RC filter like I had planned, but now I'm thinking I probably will. I'm guessing that the engine monitors sampling rate is lining up with the pressure pulses. I'm not too concerned about it at the moment. I'm just glad I was able to get back in the air again today.

[WaiexN143NM]

hi all,
thanks paul, art, and mervin for the posts and sharing of knowledge. one question i have is i wonder what the burst pressure rating for the vdo senders that we all have been using. i’ll try to look it up.
good job guys!

michael.

[builderflyer]

I flew for an hour today with the new Kavlico pressure transducer (P255-150G-E4A). It performed well; no high pressure spikes. However, my oil pressure fluctuates from 30 - 60psi with while being around 40psi 95% of the time. Occasionally it will drop to 25 for a split second.

Paul, others, I also flew yesterday with the new Kavlico pressure transducer but had a different experience than yours. In cruise the oil pressure ran about 54 psi with sometime rapid fluctuations of plus or minus 2 psi or so. I saw none of the large fluctuations that you observed. Upon landing, the pressure dropped to about 20 psi at idle. Because these pressure values are similar to what was observed with the original VDO type sender, I feel confident that they are valid for my engine.

Art,,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,,,Jabiru 3300 #261

[builderflyer]

hi all,
thanks paul, art, and mervin for the posts and sharing of knowledge. one question i have is i wonder what the burst pressure rating for the vdo senders that we all have been using. i’ll try to look it up.
good job guys!

michael.

Michael, don't know the answer to your question; however, a leak type failure of the VDO type sender is much less critical than the failure of one of these pressure transducers in that it's orifice is a pinhole, whereas the orifice in the transducers is much, much larger. I had looked for a pinhole coupling that could be installed between the engine and the pressure transducer but found nothing off the shelf. It may be necessary to custom make one. For now, the 2,000 psi burst rating of this particular pressure transducer (P255-150G-E4A) will have to suffice.

Art,,,,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,,,Jabiru 3300 #261

[WaiexN143NM]

hi all, art,
I looked up the vdo’s , looks like burst pressure is 750psi. and the swift is 300 or 450psi depending if 100/150 psi model. so the kavlico is 2000 psi burst. now what are the prv pressure spikes psi that david was explaining?
how much margin do we / have / need? the kavlico is double the price of vdo/swift , but at $137.84 im going to order one as soon as you and paul have the testing done. im hoping that as a solid state unit it will last a long time.


michael.

[builderflyer]

hi all, art,
the kavlico is double the price of vdo/swift , but at $137.84 im going to order one as soon as you and paul have the testing done. im hoping that as a solid state unit it will last a long time.

michael.

Michael, as you know, the use of the Kavlico pressure transducer (P255-150G-E4A) is a recent recommendation of Dynon. This recommendation came about as a result of numerous reports of leaks developing in the earlier Kavlico sender that Dynon previously sold. Paul and I may be among the first to install and test this unit..........so I suspect it will be a long time before complete confidence will be obtained by either of us in its use.

As you also know, there is some evidence of the successful use of the 100 psi Swift sender on the 3300 engine. John Austin of Zenith fame has been running a Swift sender on his engine for about 120 hours now and he is satisfied with its performance and durability so far. Given the low burst pressure rating of the Swift sender and the fact that it has survived for 120 hours might give Paul and I a little more comfort in running with the Kavlico and it's much higher burst pressure rating. We'll see.

Art,,,,,,,,,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,,,,,,,,,Jabiru 3300 #261

[pappas]

I am flying the Aerovee Turbo not the 3300 in my current Waiex. However, I did discard the VDO O/P sender that was attached to the front of the engine per the sonex plans. I replaced it with the Kavlico sender I sourced from Dynon. This time, I changed the mounting location from the engine to a 1/8 in npt fitting just upstream of the firewall mounted remote oil filter. I did this because everyone recommends not mounting the senders directly to the engines due to the extra vibration. 50 hours on this one and no problems.

[rick9mjn]

the question from ;Art,,,,Sonex taildragger #95,,,Jabiru 3300 #261
is ;I had looked for a pinhole coupling ??????
a may be answer to the question is """Wicks aircraft supply""" part #ea22r-o,,,,,,,restrictor fitting 1/8npt ,,orifice size .040
....good day / rick