RB30DET Damaging bearings???

[NZ_Dave]

Hey guys, I don't know if I'm posting this in the right place, but here goes:

I've got a Nissan RB30DET that I use in the NZ Drift Series over here, and I keep damaging bearings.

The person who has been doing all the work on the bottom end is a well known and reputable engine builder.

He is using ACL race bearings, and I use Total Lubricants 10w50 fully synthetic oil. I have a large sump, oil cooler (temps never exceed 120-130degrees C), high-flow oil pump - all the necessary bits for a race/drift engine, but I keep damaging bearings.

At first, I just used a second hand block in good condition, which lasted about 10 track days, then the bearings went.

After the first rebuild, it lasted around 6 track days, then melted a piston (issue now resolved) but when stripped down, the bearings were damaged again - so new ones were again fitted.

I have now done only 3 track days, and have a valve problem - and once again, the bearings are showing signs of wear (after only around 150km of running).

Any thoughts/opinions/ideas???

Thanks, Dave.

 

[Steve S]

Accusump?

 

[flacoman]

Are you sure the oil pump's not sucking air in turns?
Could the high-flow pump be pushing all the oil into the top of the engine and starving the bottom end?
Windage screen on the crank?
Just a dumb Yank asking questions
regards
Jorge

 

[Johnny248]

A guy I knew who drifted vets had something install on his engine that was like a big piston thing, worked somewhat like a caulk tube and would force more oil into the engine to keep oil in the sump all the time through turns? and then suck it back in again when the car straightened out? I'm not really sure on all the details but I do remember that.

 

[UncleRunkle]

Originally Posted By: Jdblya
A guy I knew who drifted vets had something install on his engine that was like a big piston thing, worked somewhat like a caulk tube and would force more oil into the engine to keep oil in the sump all the time through turns? and then suck it back in again when the car straightened out? I'm not really sure on all the details but I do remember that.


your reply =

Originally Posted By: Steve S
Accusump?

 

[NZ_Dave]

Hey guys, thanks for the reply's, the sump is MUCH larger capacity from standard, (from 4.25L to 7.5L) and has trap doors etc. around the pickup - I don't think the sump is a problem.

With regard to the high-flow pump, it's an N1 pump, and is what everyone else I know uses - and they have no problems.

I do have restrictors fitted in the block to stop the head "retaining" too much oil - also very common but I'm going to have them drilled out to standard size as there should be no need with the larger sump - but again I don't think this would have anything to do with the bearings.

I will find out what clearances my engine builder is setting the bearings to - but he does know what he's doing, and the application I'm using it for, so hmm...

 

[MrBeachcomber]

Bearing damage is usually due to lack of lubrication or aeration of the oil although improperly clearanced bearing shells (too much clearance) can lead to the same problem.

Personally, I'd try the Accusump solution first to see if that resolves the problem. (Worked on my L-88 in the early 70's when despite deeper sump, more oil, etc. the BBC was destroying bearings and seizing the crank during races. Turns out a vortex was forming around the intake of the oil pump allowing a mixture of air and oil to be picked up.)

 

[hustler]

We should note that drifters don't have g-loading anything like in real racing...so I'm not so sure that I would say its a starvation issue only considering usage.

 

[IndyIan]

Competitive drifting isn't guys doing donuts in a parking lot... I bet the car still see's 1g in the corners, so aeration and starvation can be a problem.
NZ_Dave,
You do have a oil pressure gauge and can see what its doing while your driving? Aeration should be easy to see then.
Maybe your builder isn't as competent as you think?

 

[BuickGN]

Besides oil related issues, how is your tune? Do you monitor knock? I'm assuming (and I may be wrong) that you're on the rev-limiter a lot. What type of limiter are you using? Most importantly, what type of damage is being done to the bearings?

 

[marc1]

Originally Posted By: BuickGN
Besides oil related issues, how is your tune? Do you monitor knock? I'm assuming (and I may be wrong) that you're on the rev-limiter a lot. What type of limiter are you using? Most importantly, what type of damage is being done to the bearings?


Exactly... don't look at the oil as the cause. This sounds like a detonation issue no question.

 

[Mitch Alsup]

Two words--dry sump (a real one, not like what they put in the Z06/ZR1.)

Two pickups one to the right front, the other to the left rear. Three oil pumps, RF, LR, pressure.
Large dry sump with oil deareator.

And don't go drifting until the oil temp is above 100dC.

 

[tdi-rick]

I think we'd all love to see the shells, that will tell a lot (or all)

De-aerating the oil is critical and very hard to do in a wet sump.
I'd imagine surge is also a huge problem with drifting, flicking from lock to lock, so I'm with Mitch, IMO any race car should be using a dry sump and at least two scavenge stages with a good de-aerater plate in the oil tank.

 

[Chris71]

I'm no expert but have you ever thought of switching to Valvoline VR-1 20w-50 or Brad Penn Racing 20w-50?

 

[jonny-b]

You could try this: http://www.rvs-tec.com/English/index.htm

I was skeptic at first, but it did fix a high pressure diesel pump, and saved some 3000$.

After that, I used it in differentials, transmissions(manual) and two engines.

It is working.

I have also found out that they are testing it at TÜV(halfway through), to have the results certified.

It could be worth taking a look at.

 

[Morpheus]

Originally Posted By: jonny-b
You could try this: http://www.rvs-tec.com/English/index.htm

I was skeptic at first, but it did fix a high pressure diesel pump, and saved some 3000$.

After that, I used it in differentials, transmissions(manual) and two engines.

It is working.

I have also found out that they are testing it at TÜV(halfway through), to have the results certified.

It could be worth taking a look at.


Hi Jonny

Do you think it works to repair some "noisy" bearing shells?
Where can I find it for sell?

Thanks

 

[jonny-b]

I have answered Morpheus via a PM.

But, I strongly believe it will fix noisy bearing shells, and bring them back to like-new condition.

 

[Nephets]

I'm agreeing with the dry sump idea. Baffling can only cure so much thanks to physics...

 

[Shannow]

baffling gives you an "accusump" solution.

It can hold the fluids in place for the pump to suck it up, but won't help it get back down there. I reckon that the baffles actually hinder return flow.

But for a drifter, I think they could work if designed properly.

 

[sprintman]

Windage tray, baffled sump, clearnces? And I'll call my mate ex Kiwi engine builder Ivan Walker (Walker Racing Engines) in Sydney to see if he has any tips.