Best method to prime the oil pump

**Mark** · #1 2 Jul 2007

Hi all

I will be fitting a new oil pump to my 3AJ Tenere when it finally gets delivered.

Does anyone have any tips on how to prime it (and any engine oilways) ?

Thanks

Mark

**Motu** · #2 3 Jul 2007

Vaseline is the best stuff to use.Pack the pump with vaseline and you can leave it forever,it will pick up oil as soon as it turns over.Vaseline will melt and mix with the oil,greases won't....oils will run out and may not get the pump to pick up oil.

**aukeboss** · #3 3 Jul 2007

The vaseline might work, never heard of that.
Since you have the clutch cover off anyway you can turn the oil pump by hand till oil comes out of the discharge hole leading to the oil filter. Make sure to have a good full oil tank.

Btw, this is very important, because of the long and relatively narrow oil lines it has happened ofthen that after a complete rebuilt of the engine it was restarted, the oil pump not filled with oil so the top end ran without oil for a sizeable amount of time.
For the same reason, do not change oil through removing the oil feed line flange next to the shift shaft.

Auke

**RtwHopeful** · #4 17 Aug 2008

Remove the spark plug(s), so the engine will spin faster, and will not start. Then run the starter motor and hope the oil pump 'catches'. Sometimes this works. Some times it does not. I did this once to my Nissan truck which has two sets of plugs per cylinder. With one set removed it still sucked in enough gas for the other set to ignite. The flames are then shot out open holes with the pistions helping. Scary, but the special effects are kinda cool.

You can also remove the oil filter and cover with the same theory that it makes the priming easier for the oil pump. When the oil comes gushing out, you're primed. The oil is always fed from the pump to the filter and then from the filter to the rest of the engine.

I forgot, you can back fill the pump from the oil filter if all else fails. Just remove the filter and find the casting passage that leads from the pump (usually the 'outside' one) squirt oil in until it backs up. At this point you can spin the engine backwards with a wrench to suck the oil into the pump; gravity might help too.

**big t** · #5 18 Aug 2008

Hi, After rebuilding my 3aj the pump would not pick up oil so my solution was to attach an airline( at low pressure) to the oil tank filler neck using an old plastic bottle cap with a small hole drilled in it. then spin the engine over with plug removed and the air pressure forces the oil through the pump round the engine and out the bleed hole.