Oil Pump Check and Relief Springs, Which is Which?
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Oil Pump Check and Relief Springs, Which is Which?
I have a used aftermarket chrome oil pump with no name. It looks like a Sifton or S&S style but I think most big twin oil pumps use the same springs right? It was leaking oil into the engine so I replaced the check ball and lightly tapped with small hammer. The one in the pump had a little ring of rust from sitting dry. The seat looks good (aluminum so no rust and looks clean). Anyway it still leaks and during working on this I noticed that the two springs are interchangeable (dumb design in my opinion but what do I know, hey after all I'm working on my oil pump with a hammer). One is a finer wire and compresses easy (currently in the relief valve) and the other is of a heavier gauge wire and takes much more pressure to compress (currently on the check ball). The lighter one was in the relief place and the heavier one to compress was on the check ball. After looking at some pictures it seems that this may be wrong. (Again I'll rant how it should not be possible to accidentally switch them). I think a previous owner (bike genius?) may have switched them. If the heavier one is wrong on the check ball then no oil will get to the engine, yikes! The heavier spring pushes hard on the check ball and seems like it would take a lot of oil pressure to bypass it where the lighter one would let oil pass easy and may fill the crankcase if that's not the one to use there. So which is which? It's very hard to compress the cap for the check ball spring (the heavy one) and the relief valve spring (currently the lighter one) looks like it barely reaches the cap. Please help. It seems that mixing these two up can lead to bad things. Which is which?
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Re: Oil Pump Check and Relief Springs, Which is Which?
Heavy one is relief(goes in the tower) light one is feed check.