Priming oil system-6g74

[disco stu]

Hi all. I'm just about at the stage installing engine into car, but having thoughts about priming oil system before putting it in.

I initially just decided to crank it to prime it up seeing it is a crank driven pump (plugs are in, manifold on), but I'm now thinking of forcing oil through the engine via either the plug into oil passage at the rear of the engine or from the oil sender. All I'll have to do this is forcing it from a bottle or hanging bottle high and rotating engine

Anyone got opinions on this, or a better idea for priming? Everything should have a coating of oil, but it's all been sitting for a while so most of it would have drained away

Thanks in advance

Stu

[erad]

Why do you have to prime the oil system? If the engine has been running, it should have oil in the critical parts anyway. If it has been dismantled, whoever did the work should have put a smear of oil if grease on the bearing surfaces during assembly. Even cranking the engine over with a socket on the front of the engine will help circulate the oil a bit. Just start the engine and let it idle for a while before giving it a decent rev.

Really, the safest way to prime the oil system is to turn the engine by hand with no load on it. This involves removing the spark plugs but it is a lot of work. The starter motor will circulate the oil through the engine, particularly if there is no compression to work against.

[disco stu]

In just trying to be particular. I've never bothered much in the past though.

I didn't have bearings out or anything like that. Everything I had apart in the top end was well oiled. Oil pump is empty. It's just been sitting for 6 months or so, so I'm guessing most oil has drained away. There would still be a film between things though.

My biggest thing is really just making sure it doesn't take too long to circulate around. I was keen to crank it without any load, but really wanted intake on before putting the engine in. Still less load with just compression compared to cylinders firing.

I'm thinking I'll just fill from the plug on the rear of the engine so the oil pump and filter are full, then crank without starting for a bit.

[stumagoo]

if its been assembled well then it should have assembly oil on all the parts - I will disconnect the spark plugs if I am worried and crank for about 5 seconds - otherwise fire it up and let it build pressure before any revs and go from there

[disco stu]

Cheers Stu.

I was hoping to get engine in yesterday, but feeling to crook so I had a play with getting oil in. I suspected that oil would leak out of the engine oil cooler connections (even though it's supposed to open based on temp) and I was right-return always open I suspect. So there isn't a way to prime it on the stand regardless. I am conscious of getting the oil pump full of oil so it doesn't take too long to pump around, so I'll leave the connection on there and pour a bit of oil in once cooler lines are attached I'm thinking

Yes-I have a habit of over thinking things! I do believe it's a learned behavior though

[stumagoo]

dude I have no issues with overthinking and asking questions - aside from it being the way I do it - its how you minimise problems

[disco stu]

Cheers. I think I used to overlook simple things when making something or putting things back together, and have to redo or similar.

I drive myself insane sometimes though, overcomplicate ideas and then eventually end up with the original idea! I bought a compound bow second hand from the US, and got it sent in pieces due to postage cost. Had to make a new press to put it together once it got here and it grew and grew to some overcomplicated thing, eventually went back to a very simple design that was my starting point which worked great, and I could have made in a weekend as opposed to the month plus I stuffed around with stupid ideas. I was sick for most of that in my own defence

[4ePikanini]

Disconnect the coil packs and fuel rail connections then crank it until the oil light goes off, or you see oil on the tappets through the oil filler.

Then connect everything and start it up.

If you want to, you can send a lung full of pressure through the pcv hoes into the crankcase as well while someone swings it over.

You can also block the PCV, then start it, wait a few seconds and then open the PCV. This will let the blow by force oil up the strainer tube.

[disco stu]

Cheers-they are some good ideas. Though my lungs aren't that good!

[TomW]

Different engine I know but when I built my 6g72 I used a cheap weed sprayer filled with engine oil, screwed a hose barb into the pressure sensor port, connected the sprayer hose and pumped away. I gave it a few litres this way then reinstalled the sender and cranked with the plugs out which gave me basically instant oil pressure.

[disco stu]

Thanks Tom. I'm plugged in to oil gallery just above/behind the oil pump. My intention is to just have a hose hanging high to pour into, but I like the pump idea. Tempted to grab one of those sprayers though, be good for transmission oil etc. Plus could use for spraying diesel as degreaser, in my povo fashion!