Oil pump gasket?

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Had my oil pan off today and decided to pull my Melling HP72 pump (340) so I could grind a sharp corner off the casting. It actually hit my Milodon pan and dented it, anyway it had no gasket. I didnt use one when I assembled it, but after holding a straight edge against the mounting flange it was not perfect. There was a .010 to .015 gap in the center. I've never checked it before so make a gasket, use PermaSeal, RTV or just do nothing. Worried it might be sucking air. Haven't checked the main cap yet.
 
After thinking about it the gap would allow oil to exit not suck air since it is after the pickup, at least that's how I see it unless someone else can give more insight.
 
After thinking about it the gap would allow oil to exit not suck air since it is after the pickup, at least that's how I see it unless someone else can give more insight.
If its on the suction side , below the oil line , no.
 
Three small blocks built and all three never had a gasket, I did ask a good friend that built these small blocks and he never used them in the Motor pool ether
 
Melling supplies a gasket and Mancini sells one. I took this pump off another motor and it did not have one. There was a post on here that a member was investigating a rear oil leak. He found this same problem and filed the surfaces flat and re-installed and the problem went away (maybe he sealed the pan better). I personally would not take the risk of metal filings getting in the engine even if it was cleaned. Looks like to me these two mating surfaces if not sealed could cause oil to run out. This motor makes 60lbs at idle hot and 70 on the highway. I'm considering the gasket. Amazing how some things get taken for granted, that machined surfaces are always parallel and true. Not so here. I'm going to use a feeler gauge and check the main cap and the pump today with a straight edge and report back. Thanks all for your input.
 
If it really is a .010-015" gap, it IS gonna leak some of the flow out. I can't see any good reason to ignore that under any circumstances. Now, how well a thin gasket will close up a .010-.015" gap across that short of a distant, I cannot say. I just checked a cap and did not find any such warpage in it.... you must have a 'Monday' part there LOL
 
Boy was I wrong. Looking at it in the light, it looked like it had a large gap. I measured it and it was spot on. I feel stupid but better. I will re-install without a gasket.
 
Looking at the surface of the pump there are some pretty course machine marks. I will put a light coat of Permatex #1 on the pump. Permatex says it is for machined metal surfaces and flanges that mate, threaded plugs and freeze plugs, drys hard and is good for 400F.
 
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