Trackmouse
Trackmouse SuperDork
3/24/17 4:15 p.m.

Oil pump is Not distributor driven, it's crank driven. Should I just disconnect the fuel pump electrical and crank till she has pressure? Or does that even matter? Engine has been sitting a year. I had dumped a teaspoon of oil in the cylinders prior to storage. 1uzfe.

BrokenYugo
BrokenYugo MegaDork
3/24/17 4:28 p.m.

Just start it, if you really feel like it pull the plugs out, unplug the coils and injectors, and then crank it until it builds oil pressure.

appliance_racer
appliance_racer Reader
3/24/17 4:56 p.m.

If I have a concern about an engine I pull the valve cover and plugs. Crank the engine with starter and make sure the oil makes it to the top. Then reinstall and fire.

ebonyandivory
ebonyandivory UltraDork
3/24/17 7:47 p.m.

Another splash of oil in the spark plug holes? Won't that seep past the rings on a cold motor? Hand crank it after that?

TGMF
TGMF Reader
3/24/17 7:53 p.m.

Eh, just start it. Cranking long enough to build oil pressure doesn't seem any better to me than just starting it.

Maniac0301
Maniac0301 Reader
3/24/17 9:54 p.m.

When I got the RS it hadn't been started in about 6 years. I pulled the plugs and sprayed a bunch of fogging oil in there. Not sure if it did anything but I don't have any oil didn't get in there type damage. I had to pull the head for a head gasket replacement and all the pistons and cylinder walls looked good. Due to a bad fuel pump and fuel filter I did end up cranking it w/out starting it quite a bit so maybe that will help.

appliance_racer
appliance_racer Reader
3/25/17 12:44 p.m.

The thing about cranking vs just firing is the load on the oiling surfaces especially rod bearings. Cranking with the starter doesn't load the bearings much as they mostly just ride the surface of the crank. If you fire the engine there's a lot more force applied to the bearings before any oil gets to them. IMO a few seconds to pull the plugs is worth it to know you took every precaution to protect the oil surfaces. Obviously it's your motor do what you think.

Streetwiseguy
Streetwiseguy UltimaDork
3/25/17 1:11 p.m.

Just fire it. It ran when you shut it off, if it blows up because you started it, its toast anyway.

BrokenYugo
BrokenYugo MegaDork
3/25/17 1:17 p.m.
TGMF wrote: Eh, just start it. Cranking long enough to build oil pressure doesn't seem any better to me than just starting it.

I think the idea there is cranking with the plugs out puts virtually no load on the rod and main bearings, versus a lot of force during cranking (compression) and even more once it catches. So it's a question of questionable lubrication for a long time at no load, or a short time at load (or if it doesn't want to start a long time at medium load).

curtis73
curtis73 GRM+ Memberand PowerDork
3/25/17 9:45 p.m.

I have disassembled more junkyard engines than I care to recall, and they all have oil in the bearings.

Taking the plugs out and spinning it to move oil is kinda pointless as you still would have motion without oil pressure. The only benefit is not having the resistance of compression, but see above... there is oil there anyway.

The real reason for priming an engine that has been sitting was a bit misguided. The main thing that needs oil is anything with direct metal to metal friction contact; i.e. flat-tappet cam lifters/followers. You can prime the engine for an hour and not get any oil on the cam and lifters, so priming is not really doing you any good anyway.

Not to mention, there aren't that many cars without roller lifters these days.

Long story short; priming will ensure that the oil pump works. I have started a few and watched as the oil pressure didn't rise, and that is where the damage happens. It doesn't take long running an engine without oil to do some catastrophic mayhem.

So on an engine with a crank-driven pump, I just make sure to dump oil where I can (under valve covers, etc) and be careful watching the pressure gauge. If it doesn't snap to life in about 3 seconds, I shut down and pray I didn't destroy anything.

So priming an engine is more diagnostic than anything. Priming it is not necessary for the engine health. But priming doesn't typically get oil on anything that is direct sliding metal-metal, like non-roller cam components which are the important ones.

I went crazy with a 350 chevy and pulled the pushrods so I could squirt oil down on the cam lobes as best I could. The result was three wiped lobes instead of all of them.

Just fire it up.

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