Oil pressure bounces

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maarten75
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Oil pressure bounces

Post by maarten75 »

The oil pressure of my dexta bounces from 4 bar to 2 bar and back. What could be the cause?
The engine has got new bearings, crankshaft, liners, pistons.
I'm not sure if this was the case after initial start already...
It has been running around 1000 km since rebuilt.

Billy26F5
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Re: Oil pressure bounces

Post by Billy26F5 »

Could the oil pump be in trouble? Otherwise I can't think of any other thing that would act like that. How often does it happen?
Sandy
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maarten75
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Re: Oil pressure bounces

Post by maarten75 »

It happens constantly, makes not much difference when hot or cold or rpm changes.

Billy26F5
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Re: Oil pressure bounces

Post by Billy26F5 »

Sorry for not asking more specifically, how many times per turn of the engine, it could be uneven wear in the oil pump or a broken tooth on the drive gear. I'm asking this to try and establish which one of the two is more likely. In both cases it requires removing the sump.
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maarten75
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Re: Oil pressure bounces

Post by maarten75 »

It looks like every combustion stroke of 1 cilinder as to compare the frequency.

Billy26F5
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Re: Oil pressure bounces

Post by Billy26F5 »

Could be a worn lobe on the driven rotor.
I definitely think this has something to do with the oil pump.
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maarten75
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Re: Oil pressure bounces

Post by maarten75 »

I hope so, thank you for your advice. I'll be checking the pump soon.

Old Hywel
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Re: Oil pressure bounces

Post by Old Hywel »

Oil pressure relief valve? Could be sticking, or not moving freely.

maarten75
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Re: Oil pressure bounces

Post by maarten75 »

That valve is mounted on the pump, can check that as well.

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