Priming the oil pump ( perkins 4108)

pcatterall

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When I rebuilt the engine I am working on I did not remove the oil pump which was in place and looked ok.
I have since read in the manual that on assembly it should be primed but as I had not dissembled it I thought no more about it.
I wanted to turn the engine over to get fuel into the fuel injector pump and to help drive out some oil in the cylinder bores.
The injectors were not fitted and neither was the oil filter. Turning by hand expunged some globs of oil from the cylinders as I hoped but I had expected to
see some being pumped out of the filter hole. There was no oil seen. I gave a quick spin ( 5 seconds) with the starter motor but there was still nothing seen at the oil filter ports.
I wonder if it needs more prolonged pumping or if the filter has to be in place. I can put the filter on and try turning some more with the starter but wonder how long I can do this for if there is any chance that the pump is not working.
 
If oil was pumped from the filter holes when turned by hand the pump must be primed, there is no other way for that to happen. Intrigued by the " globs of oil from the cylinders"
did you fill them with oil ? If so thats a recipe for problems when it is all assembled and cranking.
 
When I rebuilt the engine I am working on I did not remove the oil pump which was in place and looked ok.
I have since read in the manual that on assembly it should be primed but as I had not dissembled it I thought no more about it.
I wanted to turn the engine over to get fuel into the fuel injector pump and to help drive out some oil in the cylinder bores.
The injectors were not fitted and neither was the oil filter. Turning by hand expunged some globs of oil from the cylinders as I hoped but I had expected to
see some being pumped out of the filter hole. There was no oil seen. I gave a quick spin ( 5 seconds) with the starter motor but there was still nothing seen at the oil filter ports.
I wonder if it needs more prolonged pumping or if the filter has to be in place. I can put the filter on and try turning some more with the starter but wonder how long I can do this for if there is any chance that the pump is not working.

The manual suggests 18 to 20 seconds may be needed to pressurise the system, therefore try spinning for longer. Id not think fitting the filter is necessary although I would have done so anyway and cranked until pressure registered on the gauge or the waning light went out ........if it didn't I'd have started the engine and run it a low idle speed with my fingers crossed
 
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The manual suggests 18 to 20 seconds may be needed to pressurise the system, therefore try spinning for longer. Id not think fitting the filter is necessary although I would have done so anyway and cranked until pressure registered on the gauge or the waning light went out ........if it didn't I'd have started the engine and run it a low idle speed with my fingers crossed
Cheers VicS I will fit the filter and spin for longer.
 
Thanks for the three replies above.
The filter is secured under the mounting so I can and will fill it.
I can and will introduce oil via a tube into the port.
The pump is in the sump but the manual says prime it when assembling ..
 
Hi. Hold the fuel off so it won’t start and crank it over in 5 second bursts. Should build up oil pressure.
 
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