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- Feb 1, 2007
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I'm using an Airflow Performance fuel injection system. Up until a couple weeks ago, it has done great. I'm taking my fuel pressure reading from the flow divider, just like the Christen Kit shows. My MP/Fuel Flow gauge is actually calibrated in psi on the fuel flow side, not GPH. I don't know why, but that's what was in the box when I opened it, so I used it.
Anyway, I sometimes get some needle bounce on the fuel pressure reading at the flow divider. I suspect this is because of some air in the fuel. I will confirm that later today by connecting a clear piece of hose in between the servo and the flow divider then performing a ground run while watching for bubbles in the clear hose.
Now to my question.... While reading through the AFP manual, I saw where they strongly recommend that you do NOT use a fuel filter with a paper element which is what I have with the Christen 844 wobble pump. They say it can be a flow restriction and can ultimately cause some bubbles to get into the fuel. This should be easy enough to check for....I can simply remove the paper element and then recheck for air in the fuel using the above method.
But my question is, have any of you heard of or seen that the 844 wobble pump's filter is enough of a flow restriction to cause an issue? I find it hard to believe. There are hundreds (if not thousands) of these pumps in service on fuel injected engines. If this was an issue, seems like we would have heard it before.
Anyway, I sometimes get some needle bounce on the fuel pressure reading at the flow divider. I suspect this is because of some air in the fuel. I will confirm that later today by connecting a clear piece of hose in between the servo and the flow divider then performing a ground run while watching for bubbles in the clear hose.
Now to my question.... While reading through the AFP manual, I saw where they strongly recommend that you do NOT use a fuel filter with a paper element which is what I have with the Christen 844 wobble pump. They say it can be a flow restriction and can ultimately cause some bubbles to get into the fuel. This should be easy enough to check for....I can simply remove the paper element and then recheck for air in the fuel using the above method.
But my question is, have any of you heard of or seen that the 844 wobble pump's filter is enough of a flow restriction to cause an issue? I find it hard to believe. There are hundreds (if not thousands) of these pumps in service on fuel injected engines. If this was an issue, seems like we would have heard it before.
