Trust Oil Pump On Rb26

[trustr32]

Really sorry to bug you all but I have searched Hi and Low for the last 3-4 months and can find next to no information on these pumps but basically long story short I have just rebuilt my R32 GTR and got it running.It has all the usual oil mods with a TRUST oil pump which I bought brand new in it's box off a member on here. Had trouble with the front turbo leaking into the exhaust pretty much straight away and sent it off to get inspected. Came back fine. Put it back together but put inline 1.2mm restrictors in the turbo feeds but same issue pretty much from startup. Took it to the mechanic and he checked the car over and found that my oil pressure is sitting at 115psi at idle and 150psi at 2000rpm. He has suggested it's the pressure relief in the pump and advised changing it but this involves removing engine/gearbox/sump/pump and I need to be sure of the fix first.

So I am just wondering if there is anyone out there using the same pump or has used one in the past and can tell me do these come with dual springs from factory and if so will removing one be enough? I mean the oil pressure is WELL above the stated pressure and even with tight tolerances I can't see how it could make that amount of difference. Also could it be something else? Not the pressure relief? Could it be that there is something plumbed up wrong that is blocking flow somewhere causing a pressure buildup? I'm at the point now that I'm thinking of just replacing the pump staright up with a TOMEI so it's adjustable externally so I dont have the heartache of changing the spring on the TRUST only to get it back together to find it's still too much or worse not enough.

Any help would be greatly appreciated as I've come so close I'd hate to leave the car in a paddock until I can face it again.

Cheers Brodie

[The Mafia]

Cut a hole in your sump and get a fitting welded below the relief valve access. Did this with an RB 2530 and it was the best thing I ever did.

[kitto]

Cut a hole in your sump and get a fitting welded below the relief valve access. Did this with an RB 2530 and it was the best thing I ever did.

You could do this or fit an external oil pressure regulator. Means you have to weld an AN fitting to your sump though for the return from the external oil pressure regulator. Which means pulling the sump off anyway.

115 PSI is very high at idle. How tight was the engine built? What viscosity oil are you using?

I assume its 115PSI idle pressure when cold? What is it when the engine is hot?

[abr33]

115 psi at idle!?! shite! what oil?

[trustr32]

I'm guessing thats warm cause when I had a cheap mech gauge on it before hand it went past 120psi at cold idle and I didn't leave it long enough to see if it came down. It's cheap run in oil Castrol magnatec?? 15W40? Don't quote me on that I'll have a look tomorrow. As for the cutting a hole in the sump idea I have a Hi Octane sump extension welded on and I'm fairly sure there's not much sump left in front of it below the pump.

[KiwiRS4T]

Still got cheap run in oil after 3 - 4 months? Dump it now and get some proper oil (although I don't think it has anything to do with your high oil pressure).

[mico]

bugger that oil pressure cant be good 4 bearings. +1 for the cutting hole idea something must be jammed.

[jangles]

Still got cheap run in oil after 3 - 4 months? Dump it now and get some proper oil (although I don't think it has anything to do with your high oil pressure).

Hasn't been tuned or driven/run in yet, hence the lengthy time.

[The Dan]

bugger that oil pressure cant be good 4 bearings. +1 for the cutting hole idea something must be jammed.

Pressure won't effect the bearings in any way, shape or form.

But yes, agreed, pressre relief valve is possibly stuck from sitting and not being primed correctly.

Take it off and examine it but don't just assume you need to remove a spring. I've fit Trust pumps before and they work perfectly out of the box without any issues. The last one I did was on an R32 GTR. It has 0.0022 - 0.0024 bearings clearances and no mod to the pump in any way. It sees 8.5 - 9 bar idle cold I think.

obviously reduces as the engine warms up though

[mico]

150psi ok ? fair enough sweet

[The Dan]

150psi ok ? fair enough sweet

Yes. 200psi if you like. The bearing cannot exit the engine and the amount of load the bearing is under while in operation makes 150psi look like a poofters fart

[Piggaz]

Yes. 200psi if you like. The bearing cannot exit the engine and the amount of load the bearing is under while in operation makes 150psi look like a poofters fart

I'd hate to be behind that bloke at the wrong time!

[The Dan]

I'd hate to be behind that bloke at the wrong time!

The car or the poofter?

[Piggaz]

The car or the poofter?

The bummer!

[trustr32]

Pressure won't effect the bearings in any way, shape or form.

But yes, agreed, pressre relief valve is possibly stuck from sitting and not being primed correctly.

Take it off and examine it but don't just assume you need to remove a spring. I've fit Trust pumps before and they work perfectly out of the box without any issues. The last one I did was on an R32 GTR. It has 0.0022 - 0.0024 bearings clearances and no mod to the pump in any way. It sees 8.5 - 9 bar idle cold I think.

obviously reduces as the engine warms up though

Thanks Dan thats the sort of info I'm after. The mechanic called me on thursday and said the same thing that it's a good pump and it's most likely the pressure relief valve is just stuck. So engine out and I'll take it into him and he can have a look and see what he thinks before I go anywhere near buying a new pump. Might try and cut that hole in the sump while it's off but I don't like my chances cause I doubt there will be enough sump below the pump and in front of the extension for it but we'll see I guess.

[The Dan]

Is the gauge you're using accurate?

[abr33]

Keep in mind oil under huge pressure like anything starts being abrasive, and will chew slowly away at things, i think oil pressure over 120 psi is stupidly high unless your making massive numbers, definately would not run more than whats required on a car that is used on the street. Cue a rant anyone?

Sounds like this engine has a blockage, it should be near impossible to get that much pressure at idle, my tomie runs about 35-40 pound at idle, with restrictors and 2.5 thou crank clearance.

Hense if for example a tiny bit of crud or filter paper or rubber etc was blocking head feeds or something? Id be looking deeper than the pump.

[trustr32]

Yeah thats why I got the mechanic to look at it cause I wasn't confident in my gauge. I also thought a possible blockage I had the factory heat exchanger blocked off behind the oil filter and I know they had to block up one of the little ball valve things in that housing and i was thinking maybe they did the wrong one so the mechanic was gonna have a look at that too. There's definately oil in the head so I don't think there's a blockage at the restrictor. Also if there was a blockage such as that causing back pressure and the pressure relief valve was working properly wouldn't it just bypass the oil straight back to the sump and cause only a nominal rise in pressure or doesn't it work quite like that?

[abr33]

Even if relief was stuck, would the trust pump make 150 psi at idle?? unless its blocked somewhere for it to back up, and the relief valve was blocked at the same time, it couldnt get to that pressure at idle. let us know how mech gauge goes.

[trustr32]

Yeah I'm not sure either but it was 115psi at idle which at the moment is up around 1000rpm or was when I dropped it into the mechanic not sure if he mucked around with that at all and 150psi at 2000rpm. Am I right in my thinking (not knowing much about the internal structure of these engines) that I only have 1 oil feed for the head? ie 1 blocked off and 1 restricted? Please correct me if I'm wrong on that but if that is the case then the head feed isn't blocked as there is plenty of oil in the head. But will definately quiz the mechanic more on potential blockages too.