Managed to start my engine for the first time- engine was built and then stood for a LONG time. Can get it to start and idle with a bit of persuasion on the throttle, but oil pressure is worryingly high- the ecu is saying it is out of the top of the band, and it is causing oil leaks. Before I start thinking of engine rebuild is there anything I should be looking for? Have considered incorrect sensor calibration needlessly causing concern but I believe it is correct. Can the oil pressure regulator be changed in situ?
What can cause overly high oil pressure?
- Thread starter marco
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Fresh oil, this is the first time it has been run. As for overly high, it is a 10bar sensor and it is out if the top of the band. Have had the engine running at high idle (having to build the map from scratch so can only get it to idle at 1200ish at the moment) and as oil temps increase the oil pressure is starting to come into scale around 69 degrees. I.e. 10bar at 60 degrees...
Currently got 10w40 running in oil, and as for the regulator being modified, it is quite likely. However if it has then I am still worried about oil coolers and turbo being able to handle the pressure, as well as internal seals etc. So starting to think I might have to replace the regulator unless there is anything obvious I am missing!
Its nominally a motor from clr in miami, but it may well have been added to by who you are thinking of, if you are thinking of the same person as I am. Thinking it through there is something I want to look at (the standard oil pressure sensor location is blocked off with a grub screw- if that is too long it will block the passage), otherwise I think I will be looking to rxr the regulator.
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You'll be able to tell from just looking at the regulator. I wouldn't think for your build you'd need higher than normal pressure so if it is modified I'd swap it out for a standard one.
I don't know why some people hammer the regulators flat, it only causes issues like blown oil coolers etc.
I don't know why some people hammer the regulators flat, it only causes issues like blown oil coolers etc.
Agreed. Tbh I am struggling to understand how even with a 'modified' regulstor the oil pump is managing to make so much pressure, esp at low(ish) rpm. Infact I am starting to worry that if it is a blockage at the oil pressure sender location, that downstream (i.e. all the bits that matter) will have suffered from oil starvation.
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Quite often these "modified by hammer" regulators never open at all and the pressure sky rockets!Agreed. Tbh I am struggling to understand how even with a 'modified' regulstor the oil pump is managing to make so much pressure, esp at low(ish) rpm. Infact I am starting to worry that if it is a blockage at the oil pressure sender location, that downstream (i.e. all the bits that matter) will have suffered from oil starvation.
Fingers crossed everything is ok. I'm sure if it has only been ran for a short period it'll be fine.
Probably 10min total, all off load and in vacuum, so I cant have done much more to derisk. Even then it was done to give the oil a chance to heat up and thin out- which it did so that hopefully points to it not being completely deadheaded. Going to try to find a regulstor online today and see if I have a chance to investigate at the weekend.
Quick sitrep- removed the oil pedestal and put an endoscope as far down the holes as I could- no real blockage but holes worryingly dry. Even more worryingly the turbo oil feed is bone dry. So gut feeling is that rather than excessive oil, I have oil starvation issue. Seeing how PLENTY of oil was getting to the pressure sensor just upstream of the oil filter, and looks to be very little downstream of the filter, I am wondering if the old but unused filter was knackered. Also wondering just how expensive this is going to be. I need a stiff drink
Sitrep2. Tried cranking the engine over with filter on pedestal but pedestal off engine to look at how much oil flows. Answer is sod all oil flows through the filter. So relatively confident it is the filter that is causing the issue. However next question is whether the engine is knackered? Any way to check? Thinking replacing the filter, fitting everything back and turn engine over a few times to circulate oil then drain oil to see if there are lots of metal bits in it? Bit nervous about the turbo bearings as well tbh
In terms of modifications, oil path goes from oil pump to pedestal via an fitting. I am using a ffe pedestal to have a port for oil temp, have oil pressure sensor connected there as well, but have compared pressure readings between stock and pedestal and they are the same- as you would expect as they are on a common line. Between the pedestal and the oil filter there is a sandwich thermostat that feeds/returns from the oil cooler- have removed that for the time being to remove potential failure points. Then into the engine and I think the oiling mods are interns of increasing flow to the rotors- tbh I have forgotten all the details! Have just tried cranking with the outlet of the turbo feed disconnected so I can see if it is flowing- it is, chucking out a fair amount of oil and oil pressure reads 2.5 bar at cranking. When the turbo feed is reconnected then it goes back to 5 bar. The fact it is pumping out oil gives me reassurance that I do have oil flow, so it is less likely to be catastrophic. So back to thinking it is the oil pressure regulator.
Sitrep 4? (I think). Tried running up again and still high pressure. Drained the sump and tried to put an endoscope through the drain hole to have a look at the regulator but no joy and can't see a thing. Tried jacking the engine up by the gearbox to see if I can get clearance to remove the sump- probably enough clearance but the bolts holding the engine mounts to the block have been torqued to FT and I cant free them. The point where I am lying under the car on engine stands trying to hit a spanner with a rubber mallet is the point where I start wondering if I am in an opening scene from Casualty (other formulaic medical/ A&e dramas are available), and decided this is now the least preferred option. So going to get some thinner oil (5w30), and a turbosmart turbo oil pressure regulator and required fittings and do that. Does anyone know if the rear turbo drain on the back of the block is the same fitting as the front one? The oil pressure regulator will need a drain line and wondering about using the rear block rather than teeing into the current turbo drain line
