Matt is correct the Gold one is for gravity feed planes …. However

I encountered a 150 with a red one on it after some discussion it had been swapped from a gold one by another shop that said they called EI and had been told to swap it. So I called EI and they doubted someone had told them to swap it ….. This prompted me to ask what the danger was of using a Red one on our planes as the owner had no issues and was very diligent about tracking fuel with no discrepancies from what the unit said was used to what was really used.

After getting transferred to another tech I was told the difference had something to do with the impeller and how it spun or started to spin in the two units based on pressure. The end answer was the red one might have a very small error when fuel starts to flow and as the unit aged (years) it might get worse. I asked how much worse and he talked in terms of maybe .1 of a gallon total error over both tanks full to empty. At no time was the tech so alarmed or worried about the red one that he did not advise me that it needed to be replaced. In fact he said if it was working that it was fine to leave it.

The owner is still flying the red one … said his bladder could not take flying for that long.

1973 Cessna 150L

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