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Markus

New oil pump not pumping?

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Just had my engine rebuilt and a new oil pump and PRV fitted but when cranking over to build pressure before first start up I'm not getting any oil pressure.  I even removed the PRV to check if oil is flowing but nothing.

Can anyone shed any light on what I should do?

Cheers!

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Better ask the supplier as Mike recommends before damage is done.

how long did you crank? It took some 30 seconds on my car after the rebuild before I saw pressure on the dash board.

remove the plugs to lower the forces on the bearings.

if you have a modern filter, you can fill that with oil.

have you tested the pressure gage (with compressed air), so you can be sure it is indicating.

If the pump is not self-priming, you can fill the oil gallery by pumping oil in, this will fill the pump too. Others may know the best point for this (the oil pressure gauge pipe is hard to get to and if you do it via the prv I’m not sure if it will reach the pump or drain back in sump.

Waldi

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1 hour ago, Waldi said:

Better ask the supplier as Mike recommends before damage is done.

how long did you crank? It took some 30 seconds on my car after the rebuild before I saw pressure on the dash board.

remove the plugs to lower the forces on the bearings.

if you have a modern filter, you can fill that with oil.

have you tested the pressure gage (with compressed air), so you can be sure it is indicating.

If the pump is not self-priming, you can fill the oil gallery by pumping oil in, this will fill the pump too. Others may know the best point for this (the oil pressure gauge pipe is hard to get to and if you do it via the prv I’m not sure if it will reach the pump or drain back in sump.

Waldi

I had this problem years ago after my car was laid up for 18 months. I was told to fil up the canister/cartridge filter with oil making sure that I had the type with a non return valve in it. Back fill  the oil gallery with oil by taking out one of the blanking plugs. To my surprise it took quite a bit of oil before it over flowed. I use an oil syringe to do this. Oil pressure came back within 5 seconds to my surprise. Good luck!

Bruce. 

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9 hours ago, Markus said:

Just had my engine rebuilt and a new oil pump and PRV fitted but when cranking over to build pressure before first start up I'm not getting any oil pressure.  I even removed the PRV to check if oil is flowing but nothing.

Can anyone shed any light on what I should do?

Cheers!

Hi Markus,

This happened to me when I was trying to build pressure prior to my first start a few months ago. After some research I came across the advice to remove the oil pressure relief valve and using a squeegee bottle or a trigger oil can, pump about 100ml of oil into the opening. Make sure you get the nozzle all the way in so that the oil goes down inside to the pump. Replace the PRV nut and try again. Worked for me and it was such a relief to see the needle climb on the gauge! I was also advised that there could be an air lock in the small pipe to the back of the OP gauge so to remove the pipe from the gauge and pump some oil down the pipe also. I did both and between them they worked.

I assume you have filled the filter with oil?

Cheers,

Sean

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You can also manually prime the pump by taking the distributor off and then turning the oil pump with a tool that has a slot one end to engage with the top of the pump. You turn the tool with a drill (anticlockwise I think). You know when it begins to prime because the drill has to work harder. 

Tim

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The easier way is to pull out the PRV and pour 250ml of oil in this way - drains pretty well straight to oil pump and usually enough to prime it.

Put the PRV and spring back in and turn it over until pressure builds up.

Occasionally it's because the oil pump drive hasn't engaged properly with the drive gear, but I'd prime it before taking off the dizzy etc.

If you use Tim D's suggestion make sure you use a battery drill with a torque control so that you don't do any damage to the drive or yourself when pressure builds up and resistance increases.

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If its the new aluminium pump with the round mesh on the suction pipe, I think you have to readjust it to the correct length as in the WSM. or it will be too high up the oil level in the sump.

Not sure why they always come screwed in, perhaps to save on packaging?

John

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Exactly at this stage too. Initially turned it over with plugs in. No pressure after several seconds. Removed the plugs and the high torque starter motor span over much, much faster. Within 5 seconds the oil pressure was 100 psi, even with a bad leak from the oil filter seal at the block interface. 

I used the original oil pump as the 3 new ones I checked had much larger clearances, which would result in reduced displacement and therefore pressure. 

Colin

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100 psi is probably why the seals are leaking. I have K&N oil filter, and with 70-80 psi it is wheeping, although tight.

Waldi

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Hi Waldi,

Poor installation on my part. The seal will take significantly more pressure than 100 psi. Never had a problem before on previous cars with 100 psi pressure. Cold oil so the PRV would restrict flow out to sump, allowing the high pressure to be seen (delta P).

Colin

 

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2 hours ago, Tim D. said:

You can also manually prime the pump by taking the distributor off and then turning the oil pump with a tool that has a slot one end to engage with the top of the pump. You turn the tool with a drill (anticlockwise I think). You know when it begins to prime because the drill has to work harder. 

Tim

We did the same as Tim, struggled to get pressure after a full rebuild but using the drill worked well, sorry can't remember which way the drill should spin.

 

Good luck

Dave

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Thanks guys.

When I first noticed the gauge wasn't moving I removed the pipe as I thought it may have been air locked but that didn't help.

Then removed the PRV and cranked but no oil flowed out of the hole so poured oil into the PRV port and tried again but no oil flowing out.

By this stage I'd been cranking for approximately 5 minutes in total so I'm getting a little worried about the time it's been without pressure.

Might try making up a shaft and hitting it with the drill.

Mechanic who built the ending coming over tomorrow so hopefully all will be good.

I just want to get it done so we can go driving!

Thanks again!

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Anticlockwise for the drill if you use that method.

It does work, but takes a while to build up the pressure?

Gary

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11 hours ago, Markus said:

Then removed the PRV and cranked but no oil flowed out of the hole so poured oil into the PRV port and tried again but no oil flowing out.

Markus,

How much oil did you put into the PRV hole? When I did it I kept pumping it in until it started to flow back out the hole, then closed the PRV up again and cranked. Not sure you should leave the PRV open when cranking as pressure will not build up and nothing will flow.

Cheers

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If the pump is filled with oil and the suction sieve is submerged in oil and cannot draw air in, the pump will (should) deliver oil. No back-pressure is needed.

Waldi

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Waldi is correct. The pump will deliver oil at displacement x rpm. The pressure is generated by the resistance in the system. With the prv removed you should see most of the oil there as this is the easiest route for the oil to travel. This is assuming the oil pump is OK. If the clearances are excessive, this will reduce flow rate proportionally to tolerances.

Colin

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We have pressure!  Yay!

My mechanic came to visit with a cordless drill and a pump drive shaft and after a couple of false starts I had a lovely, and I do mean LOVELY, oil spill on the concrete garage floor.

He had that drill turning counter-clockwise for quite a while with the PRV removed but once we put the PRV back in place we had a gusher.

Everything back in place and we had ignition and lots of wonderful noise.

Still lots to do before getting back on the road but we're well on our way.

Thanks again to everyone for all the support and ideas.

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Excellent, good luck with getting it back on the road.

Dave

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Very good Markus, another tick in the box:)

Waldi

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