Forged Rb25 Lifter/possible Oil System Problems.

[DanielH]

I'm looking at it in the sense that the lifters have an inbuilt 1 way valve which should prevent them from bleeding down at all, ever. However with carbon getting trapped in there and possible thinning oil I'm assuming its just always gonna happen at times under given circumstances, and rather than trying to "pump them up" and get maximum oil flow into the lifter, I'm thinking of what could prevent the oil from escaping from the lifter when the cam lobe slams against it time after time.

Cause realistically the forces applied to the lifter are gonna be far greater than the ~80psi of oil pressure inside the motor, which is no doubt alot less after it passes through the restrictors.

[stealthfoz]

have you found the cause yet? I have the same problem, has been doing it for a few months now and seems to be getting worse. I am running poncams with vct and have run the same setup for a few years, now making 500rwkw. I am still running standard springs and lifters but don't want to upgrade yet as I cant decide if I want to go neo head yet.

[Badgaz]

Have you tried any fixes offered yet?

[DanielH]

I have fitted my oil cooler/filter relocation kit and oil temp/pressure gauges and serviced with Penrite 20/70 (hpr30) mineral, a local tuner recommended I try Fuchs 25/70 so i went with availability at the time and got a similar grade in Penrite.

I gave it a hard time on the dyno tonight, got the oil up to 105 Celsius and gave it full power runs to the limiter every time, no issues at all, maintained 5-5.5 bar of oil pressure under load at that temperature.

Unfortunately I did it all at once and have no previous data on oil temp/pressure, but the whole setup seems to work very well now.

Edited January 15, 2015 by DanielH

[89CAL]

Why are you running such heavy oil?

And if you have tuned the car surely the rings have bed in now and you can go to synthetic oil

5bar at what RPM? And what sort of oil pressure are you getting when its idling cold?

[DanielH]

I'd like to know how you think it is "such heavy oil" ? I'd prefer to have the thickest oil I can get away with in there so that when I do get everything hot it doesn't thin out and turn to water.

I have 4.5 bar at cold idle, and around 5.5 bar at any rpm above ~3000, obviously that's where my oil pump relief valve is fully open as it will never go much higher than that.

As for the mineral oil, do some research, synthetic oil has its downsides too, I'm happy trying different things and using what works for me, and so far this is working well for me.

[jiffo]

Something to consider is that with cold engine temp, high viscosity oil and a high flowing oil pump, not just the oil pump relief valve opens, the oil filter bypass valve would be well open too = no filtration.

It's a delicate balance selecting the correct oil once one begins modifications to pump, bearing tolerances and so on.

[GTSBoy]

I'd like to know how you think it is "such heavy oil" ? I'd prefer to have the thickest oil I can get away with in there so that when I do get everything hot it doesn't thin out and turn to water.

I have 4.5 bar at cold idle, and around 5.5 bar at any rpm above ~3000, obviously that's where my oil pump relief valve is fully open as it will never go much higher than that.

As for the mineral oil, do some research, synthetic oil has its downsides too, I'm happy trying different things and using what works for me, and so far this is working well for me.

Nearly every aspect of what you are saying has flaws. Reconsider your choices. Oil with a range in the region 5-50 makes so much more sense, for all the opposite reasons that you have chosen to use to select heavy oil. And synthetics are so much more able to handle the high temperature abuses of passing through hot turbo cores and so on.

[89CAL]

I'm running 10w40 on a Fully forged engine in a town that sees 35 degrees in summer quite often, I've never had an issue. Admitedly I'm not racing the thing, but the lowest pressure I've seen at idle was about 11psi. This was on a hot day, stuck in a multi story car park trying to get out.

General rule is 10psi/1000rpm, if you are seeing that pressure with a good synthetic oil, there is nothing to worry about. Mine is nearly double that figure usually driving around, so how is a heavier oil better then running my 10w40 synthetic?

Also consider that by regularly running the oil over the relief, you are heating that oil up even more. I'm aware this is not such a big deal as it is in hyrdaulics with 1000's of PSI of pressure involved, but it still plays a role.

I'm sure there are plenty of people on here that will vouch for the same/similar weight oils to mine, I'm just struggling to see where the need to run such a heavy oil, It just doesn't make sense to me for an RB25

[DanielH]

If you weren't all trying to bash everything I've done through this entire discussion maybe you would all remember I had a problem with my lifters emptying themselves at high temperatures and load with 15/40 oil, having since gone to a thicker oil and getting it up to a reasonably high temp I no longer have any issues, my lifters are staying dead quiet, I have good oil pressure on cold start and good oil pressure when the oil is at 105 degrees C, why on earth would I go back to a thinner oil just cause it works for everyone else?

It has been established by many that I have larger cams than what I realistically need, which I'm not bothered about what soever, I also have heavy valve springs and old lifters with lots of K's on them, so what works for every other bloke might not be quite enough for my setup.

Go and have a bit of a look around at people who race old Holden 6's and the oil they use, you would soon realise HPR30 isn't a thick oil in the scheme of things.

I came on here looking for anyone with real world experience with this issues, instead I got 10% good advise and 90% criticism over my setup and people bashing my ideas which solved my issue, I no longer care what anyone thinks I just thought I would post up my results for those who might ever have the same problem.

Edited January 16, 2015 by DanielH

[Badgaz]

read the link i posted in page 2 it helped me understand what GTSboy was saying and why i was wrong about oil being thicker....i don't think people are bashing you. 90% of what people are running isn't 75 weight.

[AngryRB]

Its a band aid fix for lifters that should of been upgraded, as for the rest of the engine it will just have to cop it sweet for the first 20-30mins, does this engine do the zututututututut as well?

Edited January 16, 2015 by AngryRB

[89CAL]

Its a band aid fix for lifters that should of been upgraded, as for the rest of the engine it will just have to cop it sweet for the first 20-30mins, does this engine do the zututututututut as well?

Basically what im saying. Its hard to say you have fixed the issue when I can run 10w40 and my lifters are silent. Better to find the real issue then have a major problem.

End of the day it doesnt bother me what oil you run. I tried to help

[Scott Black]

Yeah pretty much instead of fixing a problem you decided to hide it at the cost of increased wear on the rest of the engine, alot of older holdens and ford's run thicker oil as there engines were designed around larger tolerances, and bigger galleries etc. My boss uses 20/50 in a high powered 351c from the 70's doesn't mean I should put it in my 2013 pulsar

[DanielH]

But what's to say that I may spend hundreds (which I don't even remotely have) on 24 new lifters and I won't still have the same issue? I'm pushing the factory hydro lifters beyond the intended stress Nissan ever had in mind for them, I have an event in 1 week that I'm entered in, I could still be scratching my head sorting this out.

Not 1 single person running cams as big as mine with similar valve springs chimed in with a definitive answer or advice for me to follow, I was only given opinions by many with varying setups from mine, I tried something that made sense to me and succeeded, and was able to do it affordably and on time.

As for the engine having to suffer on cold starts, it's not registered let alone a daily so no problems being driven straight from cold, and you's still seem to think I've chosen some honey-like hpr60 or something.

Edited January 16, 2015 by DanielH

[Dale FZ1]

Often it's useful to just try something and see the results for yourself.

I know one of the high end WTAC runners is using HPR30. Primary benefit of the synthetic lubricants is long service life due to the resistance to shear. If this is not a registered car and effectively used for short run events, there is some good logic in trying different spec oils especially if you dump the oil after an event. What are we talking about - an hour or two runtime?

I do note that your first post in this thread referred to the car getting a hard time on the street though...

Removing/refreshing your lifters does not require that they be replaced. They are easy, but time consuming, to disassemble then scrub clean accumulated varnishes and reinstall. Buildup of that stuff does not allow older lifters to perform as new, but when cleaned they are effectively renewed.

I'm using a 8.9mm 265 degree cam spec with Performance springs, freshened lifters and a 15/50 oil. No issues or valvetrain noises cold or hot and track only use.

Good luck with your powercruise event, and please post up how things go.

[DanielH]

Thanks for your input mate, you are right about me saying it will see hard street use, it did and eventually will, I accidentally let the registration expire and it is not mod plated (VS commodore ute) so for now it's just shed life and powercruise, after that It will get a service and eventually rego, I will consider dropping the oil weight at that stage and seeing how it performs.

And you are right about the lifters, perhaps if the issue continues or returns after I go to a thinner oil I might have to consider pulling my cams and giving them a clean.

[DanielH]

Just to clarify something, I made a mistake when I posted the oil I chose, it is Penrite 20w60 performance mineral, and I was recommended 25w60, not sure why I put 70 down, brain fart I guess

Apologies to all effected.

[Dasmbo]

Did you get the right springs for the 9mm lift cams you might possibly getting lifter binding

[MrStabby]

IF the lifter problem is due to gunk (no idea if that's a thing), then that's an indicator you need a better oil, or you need to perform more frequent oil changes. IMO you should reconsider going to a synthetic, as they perform much better at higher temps and tubos = high temps. Also, since synthetics are considered a premium product they have better additive packs.

Of course, you dont want to shell out for a synthetic while you trying different viscosities where you will probably dump the oil early. I would choose a viscosity based on the lower of;
1. the 10psi/1000rpm hot guideline

2. what keeps your lifters quiet

Once you've settled on viscosity, change over to a nice full synth of the same hot viscosity (the higher number). Note that the Xw-Y notation describes ranges - 40 weight spec is 12.5-16.3, and 50 weight spec is 16.3-21.9 so the heaviest 40 and the lightest 50 are the same viscosity at 100 deg C.

Quality oils used at sensible change intervals will slowly clean the inside of your motor (and lifters) so you may find that #2 above comes down as the lifters clean up.