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Tru track fuel pressure transducer

pokey

Active Member
All
I installed a tru track EFIS/ems system in my rv4 7 years ago. Fluctuating (wildly) fuel pressure led me to replace the engine driven fuel pump.

The problem continued. Doing what I should have done first, testing the indication against a mechanical calibrated gauge revealed the problem to be just indication.

Tru track no longer makes or supports this system so I?ve got an orphan needing parts on my hands. The transducer says ? made in Germany ? that is the only clue.
And what I would like to replace next.

I?ll try dynon in hopes theirs will work. If not what?s my next move?

Thx
Bill
 
most transducers send a 12v or 5v (I forget which is standard) pulse for a given unit of flow. The EFIS should have a calibration setting to adjust the number of pulses that equal a gallon. I would call trutrak and ask if the units they supplied were of this type and if an EI red cube can be intalled in it's place. I am guessing that it can.

Larry
 
I think he was asking about pressure.

Bill,

If it's an older system, it's almost certainly a VDO. Is it a small metal cylinder with a 1/8"npt threaded fitting on one end and and electrical terminal on the other? Something like these:
https://www.google.com/search?ei=yw1LXOTyNI6q_Qb-zpyYCw&q=vdo+pressure+sender+&oq=vdo+pressure+sender+&gs_l=psy-ab.3..35i39j0l2j0i22i30l7.4012.4012..5718...0.0..0.422.422.4-1......0....1..gws-wiz.......0i71.kNKh7NGytgM

If so, remove it from the engine and look at the small hex fitting at the 1/8 npt end. there should be some numbers stamped on the flats. They will tell you what the pressure range is, likely marked in bars rather than psi. Do a google conversion from bars to psi, & it'll probably be around 15-20 psi sender for carb, or around 60 psi for injected. Assuming that I'm guessing correctly, replacements are common as dirt on ebay, Amazon, and your local auto parts house.

If the above doesn't apply, the next most likely would be a Kavlico style sender, like:
http://www.kavlico.com/kavlico-pressure/pressure-products

Also available on ebay, Amazon, etc. There are Chinese knockoffs that are almost an order of magnitude cheaper than the Kavlico branded senders.

EDIT: The two styles operate very differently; they are not interchangeable without modifying the way the gauge/EMS works. The VDO expects DC to be fed to its single terminal and varies its resistance which is sensed by the gauge/EMS; the Kavlico expects DC to come to a separate supply pin, and outputs a varying voltage to the gauge/EMS.

Charlie
 
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