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oil pump rebuild

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adriangsmith:
I rebuilt my oil pump alongside my engine rebuild.
I now cannot get any oil up to the main gallery.
The scavenge side of the pump is working well as it picked up the pint of oil i tipped down the rocker cover and deposited it back in the tank.
But what ever i do i cannot seem to get any thing from the pressure side of the pump.
Is it possible to put the rotors back together wrong?
I know i matched the dots on each pair of rotors with both facing upwards during assembly.
The pressure relief valve moves easily, maybe a little to easily but still has pressure against it.

Any ideas anyone??

Gixxer-18:
I read somewhere that you should fill the pump with Vaseline to prime it before trying to start the motor?
Nigel.

K2-K6:
Worth having a look over on the thread "oil pressure motor rebuild" by MrDavo as toward the end of the thread it discusses exactly this, so there's quite a walk through it on there.

The pressure side of the pump is only fed by the oil line coming down from the oil tank so you can only look at that for your feed, and not the sump.

Vaseline packed into pump head will often get reluctant pumps sucking again so worth doing.

If you have air on both sides of a pump (in and out)  it will quite often not want to start. Another way that may get it to prime is to drain the oil tank and feed pipe if the oil's cold and thick, then get the oil warm and slowly pour it in as it's more likely to run through the pump head and get it filled.

Simpler method maybe to point a fan heater onto the oil pipes and base of engine for half an hour to get the viscosity down.

Once going, they never have a problem, but can be slightly reluctant to get primed.

Trigger:

--- Quote from: adriangsmith on December 26, 2016, 06:41:40 AM ---I rebuilt my oil pump alongside my engine rebuild.
I now cannot get any oil up to the main gallery.
The scavenge side of the pump is working well as it picked up the pint of oil i tipped down the rocker cover and deposited it back in the tank.
But what ever i do i cannot seem to get any thing from the pressure side of the pump.
Is it possible to put the rotors back together wrong?
I know i matched the dots on each pair of rotors with both facing upwards during assembly.
The pressure relief valve moves easily, maybe a little to easily but still has pressure against it.

Any ideas anyone??

--- End quote ---

Did you put in new O rings ?
Have you primed the pump ?
And don't try to turn the engine on the starter motor until you can see oil at the top end.

adriangsmith:
yes new o rings fitted to the pump.
Didn't prime the pump though. so i guess sump off, pump out and vasalene time!  :(
I have also tried reverse filling by filling the main gallery with oil. letting it sit and kicking it over every 2-3 hours to try and release any trapped air.

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