Hi all, first time poster.

Thought i'd introduce myself with some explanation from my understanding on the RB engine oiling design flaws as my contribution to joining the forum. I've noticed this has been quite a debated topic however i just want to help spread the word in case some people aren't fully aware of the issues. Which i feel is an important role because everytime an RB goes bang, i die a little inside.

Now let me get started. As you all know, the oil pumps in the RB engines aren't all that strong. However, this isn't actually the major issue. In fact switching to a stronger, higher flowing pump will actually amplify the problems.

The engine design has a number of major flaws associated with the oiling system that has led to the premature death of many, many RB26's.

Number 1. The major problem is that when the engine operates at high rpm, it drains all of the oil from the sump and circulates it all to the head leaving the bottom end dry. Now i don't think i need to explain what a lack of lubrication does to a bottom end bearing spinning at over 130 times a second. But it isn't good and results in a lot of broken engines. If your oil setup and engine is stock, it's always a good idea to keep any periods of time at high rpm to a minimum because that is the killer. And if you are pushing more power than standard, try keep power under 480hp at the flywheel as the stock bottom end will not hold much more than that.


Number 2. Oil pump failure, the biggest killer isn't the pump itself, but the crank collar. A standard pump will suffice as long as the crank collar is changed out with an aftermarket variant. A big problem that most people have is they buy a big strong, high flowing oil pump thinking it fixes their issues. However if you have read Point 1, you will know that all a higher flowing pump will do is send more oil up to the head at a faster rate. Not a good idea.


Number 3. Oil galley size. Fitting oil galley restricted is a small fix that doesn't quite eliminate the problem of sending all oil to the head, however it does slow the process down and is a worthwhile modification if you have already taken the head off.

Number 4. Crank housing pressure, now this involves a bit of work, but is worth it to ensure longevity at high rpm. The reason why the oil flows to the head, and stays in the head is because crank pressure won't allow it to flow back through the oil return feeds.

There are a couple of fixes for this, the first is installing more oil return lines feeding back into the sump, however if you want to go that step extra what i am doing in my current build is installing a small secondary pump at the back of the cylinder head that activates at >50% throttle and that will help return the oil back to the sump.

Some smaller steps you take can be slightly overfilling with oil. However with this you run the risk of blowing rings and all that fun stuff.



Thanks for taking the time to read, this post has turned out to be a little longer than expected but i guess i'm just bored at the moment. I hope this has at least helped in some with anyone wondering about these engines.

Thanks,
Noctis

Good info. Thanks for the post and welcome!

interesting!!

I've mostly seen just the tapping of the back of the head, can you elaborate on this mini pump? Welcome to NICO.