oil sender probs

[Frank mellin]

have recently fitted an oil pressure gauge with a remote sender unit to my Nanni 3.75he diesel engine.
Worked fine for couple of weeks with pressure around 50psi.
Now takes about 5 mins to come to life when starting engine!!
Have been reading up and seems like these sender units are nothing but trouble.
Have tested gauge and it is fine.
There have been complaints about the microbore hole in the sender being so small that it easily blocks and indeed it is very tiny!
If I enlarge the hole will it affect the working.
Only other option seems to be to keep sending them back as not fit for purpose.
(one unlucky person has got through 6 in a very short space of time ,some only lasting couple of days!!)

 

[RichardS]

I don't know why the sender is so short lived but there should be nothing in the engine oil which could cause even the smallest bore hole to block. The oilways for bearings and the bearing clearances themselves are microns.

I would not have thought that widening the bore would affect the pressure on the diaphragm inside the sender but it shouldn't be necessary.

Richard

 

[jiris]

No idea why these probes are failing. A poor general quality comes to mind first. As for the hole: the purpose of the small diameter is to provide some degree of buffing minimising vibrations from sharp and fast variation of pressure caused by the action of oil pressure relief valve. Providing the filter is functioning properly, the hole shouldn't get blocked. Making it larger won't do any good to the probe.

 

[vyv_cox]

I made the mistake of adding an electric oil pressure gauge to my BMC 2.2 diesel. It runs fine with no knocking or suggestion that pressure is low. When hot it registers 1 psi when driving and has done since day 1. Cannot possibly be correct.