850 oil pump relief valve

Before we left town yesterday, I reassembled the oil pump after lapping and reinstalled it. I also cleaned the relief valve assy and assembled it (cup,spring, no spacers, cap nut) and noticed that if you shook the unit, it rattled. SEEMS to me that it shouldn't do that because it means that the spring does not firmly hold the cup closed and would therefore allow oil pressure "relief" at idle. Is it supposed to rattle? I realize that the correct way to sort this out is with an oil pressure gauge and the bike running but I don't have one available. The relief valve had no spacers installed and I have been advised that oem was from 0 to 2 spacers. There are no indicators that the oil pressure was low but OTOH, I have not disassemble the crankcase so I haven't seen the rod bearings...

Yeah...I know, "get an oil pressure gauge"...

hi mike,you got it right ,it should,nt rattle there are shims available to take up the slack

I would say you are OK ( went and checked one i have here and it rattles with no shims). If you look at how far the piston has to travel to reach the relief port it is quit a way. but the best thing is to check oil pressure.

MexicoMike said:

noticed that if you shook the unit, it rattled. SEEMS to me that it shouldn't do that because it means that the spring does not firmly hold the cup closed and would therefore allow oil pressure "relief" at idle. Is it supposed to rattle?

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Apparently so, according to Mick Hemmings!

In Mick's NOC Heavyweight Twin Engine Restoration video he demonstrates this by fitting three shims to a relief valve, however the relief valve doesn't appear to rattle when he shakes it, so he removes a shim, saying: "I like to just hear them rattle slightly" but he reckons it's just a bit too loose, so he replaces the third shim again.