Jump to content


Photo
- - - - -

Question About Priming Oil Pump Before First Startup


Best Answer BaronVonchesto , 16 July 2019 - 01:54 PM

Well got it sorted. followed all the advice. put int he pressure relief valve, opened the banjo filled the block with oil, pushed the car backwards in gear and put the banjo back in.

 

then cranked it and 5 seconds later the pressure was up to almost 50 psi!  :proud:

 

thanks everyone!

Go to the full post


  • Please log in to reply
24 replies to this topic

#1 BaronVonchesto

BaronVonchesto

    Mini Mad

  • TMF+ Member
  • PipPipPipPip
  • 295 posts
  • Location: Kuala Lumpur

Posted 12 July 2019 - 05:14 PM

So i've finished refitting my newly rebuilt engine and am just about ready to start it up for the first time! Excited! but i cant get the oil pressure up and was wondering if im doing anything wrong.

 

I'm cranking the engine in 10s bursts, and i did this about 5 times but the oil pressure gauge didnt budge from 0.

 

I did fill the oil filter with oil, but not the oil pump when i put it on the crank. all i did was take the oil pump out of the box, squirt in some assembly lube, slap on the gasket and bolt it straight to the cam.

 

also i've removed the oil pressure bullet and spring. and of course i've ensured that i did pour over 4 litres of engine oil (dipstick is slap bang in the middle). no spark plugs fitted.

 

am i missing anything?


Edited by BaronVonchesto, 12 July 2019 - 05:29 PM.


#2 unburntfuelinthemorning

unburntfuelinthemorning

    One Carb Or Two?

  • TMF+ Member
  • PipPipPipPipPipPipPip
  • 924 posts
  • Location: Bedfordshire

Posted 12 July 2019 - 05:22 PM

You won't get any oil pressure with the relief valve not fitted.  Do you mean there's no oil coming out when cranking?

 

You can remove the banjo bolt above the oil pressure switch and insert oil here to reach the pump.  Replace the bolt and try again.


Edited by unburntfuelinthemorning, 12 July 2019 - 09:15 PM.


#3 BaronVonchesto

BaronVonchesto

    Mini Mad

  • TMF+ Member
  • PipPipPipPip
  • 295 posts
  • Location: Kuala Lumpur

Posted 12 July 2019 - 05:28 PM

oh! for some reason i thought that the pressure relief valve should NOT be fitted when trying to prime the pump.

i shall put it back in and crank it again. how long should i crank it for you reckon

in the past i only needed to crank my engine for about 10-15 seconds before oil pressure would rise, but this was with my engine sitting for weeks without being started.

 

for a newly rebuilt engine it might take longer no?



#4 cal844

cal844

    Crazy About Mini's

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 6,566 posts
  • Local Club: www.scottishmini.net

Posted 12 July 2019 - 06:05 PM

10-15 seconds running while waiting on pressure is ok, I wouldn't go any longer.

Are you using the ball and spring or thimble and spring relief valve?

#5 Moke Spider

Moke Spider

    Crazy About Mini's

  • TMF Team
  • PipPipPipPipPipPipPipPipPipPip
  • 8,941 posts
  • Location: NSW
  • Local Club: South Australian Moke Club

Posted 12 July 2019 - 07:23 PM

I have always done as Unburnt suggested and prime the pump via the Banjo Bolt hole, an Oil Can is helpful here to avoid a mess.

 

Then I wind away for what ever it takes to get the Oil Pressure up, 20 - 30 - 40 seconds, but rare it needs any longer than that. I doubt from new you'll get it up in 10 seconds, but without priming the pump first (and after filling that hole with oil, put the car in gear and roll it back a few feet to draw the oil in to the pump), you can crank until the cows come home and still not get oil pressure up.



#6 BaronVonchesto

BaronVonchesto

    Mini Mad

  • TMF+ Member
  • PipPipPipPip
  • 295 posts
  • Location: Kuala Lumpur

Posted 12 July 2019 - 07:39 PM

so just to be clear on what to do here:

 

1) put pressure relief thimble and valve back in.

2) remove banjo bolt and squirt oil into the pipe. to fill it up (do i squirt into the block too?)

3) put it into 2nd gear and roll the car backward 2 or 3 meters

4) then crank the engine for 20-40 seconds to build pressure

 

did i get that right?



#7 DeadSquare

DeadSquare

    One Carb Or Two?

  • Members
  • PipPipPipPipPipPipPip
  • 1,120 posts
  • Location: Herefordshire
  • Local Club: Herefordshire Motor Club

Posted 12 July 2019 - 07:58 PM

so just to be clear on what to do here:

 

1) put pressure relief thimble and valve back in.

2) remove banjo bolt and squirt oil into the pipe. to fill it up (do i squirt into the block too?)

3) put it into 2nd gear and roll the car backward 2 or 3 meters

4) then crank the engine for 20-40 seconds to build pressure

 

did i get that right?

 

 

N0.

 

Fill the block.



#8 DeadSquare

DeadSquare

    One Carb Or Two?

  • Members
  • PipPipPipPipPipPipPip
  • 1,120 posts
  • Location: Herefordshire
  • Local Club: Herefordshire Motor Club

Posted 12 July 2019 - 07:59 PM

 

so just to be clear on what to do here:

 

1) put pressure relief thimble and valve back in.

2) remove banjo bolt and squirt oil into the pipe. to fill it up (do i squirt into the block too?)

3) put it into 2nd gear and roll the car backward 2 or 3 meters

4) then crank the engine for 20-40 seconds to build pressure

 

did i get that right?

 

 

N0.

 

Fill the block.

 

 

 

And replace the banjo.



#9 gazza82

gazza82

    Up Into Fourth

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 2,104 posts
  • Location: Bucks
  • Local Club: TMF+

Posted 12 July 2019 - 08:50 PM

If you can turn the engine over backwards a couple of times it will suck oil back into the pump too.

#10 timmy850

timmy850

    Camshaft & Stage Two Head

  • TMF+ Member
  • PipPipPipPipPipPipPipPip
  • 1,883 posts
  • Location: NSW, Australia
  • Local Club: MITG

Posted 12 July 2019 - 09:49 PM

There is a nice summary here

https://www.7ent.com...ni-storage.html



#11 DeadSquare

DeadSquare

    One Carb Or Two?

  • Members
  • PipPipPipPipPipPipPip
  • 1,120 posts
  • Location: Herefordshire
  • Local Club: Herefordshire Motor Club

Posted 12 July 2019 - 10:10 PM

There is a nice summary here

https://www.7ent.com...ni-storage.html

 

If you look at picture 4, cranking the engine is going to be difficult.



#12 Magneto

Magneto

    Super Mini Mad

  • Members
  • PipPipPipPipPipPip
  • 618 posts
  • Location: Kansas City, USA
  • Local Club: KC MINI Club

Posted 13 July 2019 - 01:25 AM

I've had them still not prime after all this, so I go ahead and light it off, if it doesn't come up after 5 sec or so I shut it off and tear it down again. I've only had to do this once, and the pressure came up the instant it started, just wouldn't do it on the starter motor. Every other one I've done comes up in 20-30 seconds maximum. I then continue to crank it for 10 sec or so after the pressure comes up. With no plugs you're not going to overheat the starter motor in 30-40 seconds.



#13 Rorf

Rorf

    Super Mini Mad

  • Members
  • PipPipPipPipPipPip
  • 619 posts
  • Location: Cape Town

Posted 13 July 2019 - 08:31 AM

Start a newly built engine without without oil pressure and bearing damage is done, taking off 1000 of miles of useful engine life.

 

If an engine had been correctly built and the oil pump fitted correctly oil pressure should come up after about four ten second bursts on the starter. You will actually hear the engine slow down slightly as the oil pressure builds up.

 

I have always put a bit of multipurpose grease in the oil pump before fitting. Of course the new pump should be dismantled and cleaned up - the odd casting burrs here and there etc to be filed off.



#14 DeadSquare

DeadSquare

    One Carb Or Two?

  • Members
  • PipPipPipPipPipPipPip
  • 1,120 posts
  • Location: Herefordshire
  • Local Club: Herefordshire Motor Club

Posted 13 July 2019 - 08:50 AM

Start a newly built engine without without oil pressure and bearing damage is done, taking off 1000 of miles of useful engine life.

 

If an engine had been correctly built and the oil pump fitted correctly oil pressure should come up after about four ten second bursts on the starter. You will actually hear the engine slow down slightly as the oil pressure builds up.

 

I have always put a bit of multipurpose grease in the oil pump before fitting. Of course the new pump should be dismantled and cleaned up - the odd casting burrs here and there etc to be filed off.

 

Every car that comes off a production line, is started and driven off while the oil pressure builds up.



#15 unburntfuelinthemorning

unburntfuelinthemorning

    One Carb Or Two?

  • TMF+ Member
  • PipPipPipPipPipPipPip
  • 924 posts
  • Location: Bedfordshire

Posted 13 July 2019 - 09:09 AM

Every car that comes off a production line, is started and driven off while the oil pressure builds up.

 

Many engines have oil pumps in the sump submerged in oil which eliminates priming problems.






0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users

Mini Spares