A respected source advised me to pack my oil pump with Vaseline before turning over my fresh motor to assist with priming..... Is that some lost, forgotten secret, some disproven folklore or simply voodoo? o No:
Ditto! It's the only way you can build a Mazda rotary engine, slather it on all the rotor side seals and apex seals to hold them in place during assembly. Built one in the 70's. TexasJohn
Yes, some people use chassis grease, and that is a big no no. Petroleum jelly dissolves easily in motor oil, but some have reservations about that. As long as you make sure the pump primes before you fire the engine. Sometimes they will by turning the pump with a drill. Anytime you disturb the timing cover seal, you should check the pump prime.
Never have done it, never will do it, on a new build. Simply not required. That's a service manual technique adapted to the aftermarket by folks building oil pumps and shipping them to customers. The reason for doing it is the same as the the factory's for adding that procedure in the first place. The line techs simply bolted the oil pump together and on the engine, and started it. No pre-lube procedure. I know TA does this with new covers, and they have to, for the exact same reason.. they can't count on every customer pre-lubing the engine. For them it's good insurance, and the downsides are minimal. But to translate that requirement to someone building the motor at home, and following the correct procedures for pre-lubing the engine, is simply wrong. I just numbered the latest block here last night, it's number 65, since I started keeping track of them in 2003. I put the pump together dry, then rotate the motor up on the passenger side a bit, and pour oil directly into the oil filter housing.. then screw the filter on. You just have to get the gears a little bit wet. Rotate it back upright, and then spin the oil pump shaft, with the tool, and a drill. The faster you spin it, the quicker it will prime. I has not mattered if I have done this 2 minutes, or 2 weeks later. For those of you building yourself a new cover at home, and putting it on the engine in the car, then simply pour in a touch of heavy pre-lube while you spin the gears, before putting the pump on the engine, and then pre-lube it as normal. Better auto parts stores sell the pre-lube under several brand names, Clevite calls it "Bearing guard". It comes in a small 2 to 4 ounce bottle. I personally don't want anything but oil and other liquid pre-lubricants in a new engine, at the most critical moment in it's life. that's one reason, and a bit anal I will admit. A more practical reason is that if you use petroleum jelly in the pump, you need to spin that drill and pressurize the engine for several minutes, to attempt to flush that semi-solid thru the system as best you can. In the process, you wash off all the good extreme pressure pre-lube you should have been using to assemble the engine. I spin the oil pump until it pressurizes, and then stop. Takes typically about 15 seconds. Every now and then I build an oil pump for a customer in another state. In that instance, I use the Bearing Guard referred to above, and seal the pump passages with heavy tape. Never been an issue.
I'm with you Jim. I don't want sludge (Vaseline) in my brand new engine possibly blocking oil to critical areas such as cam bearings while waiting for the engine heat to melt it. Sure it may all be liquified in a minute but that first minute is the most critical. My favorite way to prime is by putting 20-50 motor oil blended with breakin oil additive (Comp cams) into the inet and outlet ports of the timing cover while turning the oil pump one way then the other with a full oil filter attached. (cover needs to be off and laying down). Then carefully install cover on motor. Prime with drill. A good sign is when oil pressure primes quickly AND slowly falls. Side story: I had one that built pressure but dropped instantly when you stopped priming. Had to take it apart....machine shop had mis-positoned the cam bearings. They came out to my house and drove them all out and put them back in. Then I tried installing the cam and it was tight. They said it would be fine and will loosen up. Yeah, right. I had them install a new set I had on the shelf. Then the cam spun freely.
I figured most the petroleum jelly would stick in the oil filter until some heat got into the engine to thin it out. Interesting about just needing the gear to be a little wet. I've had pumps refuse to prime after having the timing cover off, but not disassembling the pump. I'll keep that in mind. This last time I had the engine apart I simply poured oil in the inlet and outlet of the oil pump from the backside of the timing cover prior to bolting on the cover and it had oil pressure almost as soon as I put the drill on it.
Jim, a follow up question. When you spin the pump to prime it, do you just go till you show a little pressure, or until it pumps out the top of the push rods? Seems like for only 15 seconds it you must just go until you get pressure. Just want confirmation for the future whenever I get done with this body and can then work on the engine. PS. Ball park machining only costs on 455 block, line bore, deck, bore, hone, crank grind, sonic check, clean etc. Is around $1500 in the zone or should I budget more up to $2000? or more?
Jon, All the upper end components are assembly with Joe Gibbs assembly lube, rockers are oiled, so there is no need to worry about getting oil up the pushrod. This is much much better than assembling the engine dry and then trying to use the prelube procedure to oil those parts. That happens very quickly once the engine starts. So yes, all I am doing is verifying that it will have pressure when it starts, and filling the oil galleys. Just block work, with no rotating assembly stuff or balancing, but including everything for a finished ready to assembly block, including the oil mods, your looking at $1250.00 Crank grind depends on standard grind or offset, standard is $205, .050 offset grind/indexed cranks (470) go for $369. Your cores of course. Add piston, rod and balancing misc work then budget 2K to have get something to put together, and you will be plenty safe. JW
I simply oil the pump gears during assembly and fill the filter with oil, if the engine is on a stand you can rotate it slightly so little oil is lost from the filter when screwing it on. Run the pump with a drill and priming tool, a distributor housing and shaft works great and the pump always picks right up for me using this method.
