Fixing Oil starvation problem 3.4 engine
07-12-2017, 10:36 PM
#1
Rennlist Member
Thread Starter
Fixing Oil starvation problem 3.4 engine
As many of you may have known I had my 3.4 engine rebuilt and suffered a failure at the track soon after having the engine rebuilt. hence I had to rebuild the engine again. I obviously want to prevent this from happening again. I spun a rod bearing (#6) and it happened while I was accelerating on the track. Apparently I was victim of a common problem on the M96 engine. Oil Pressure was down after every lap and reached 2 at full acceleration. I should have stopped there in hind sight.
Im running Michelin Pilot Sport Cup tires and take the car to the limit. Sadly I think that I would have avoided this problem with a Deep Sump Kit. Yet Im not sure since PCA has articles saying oil starvation is not a problem on the M96 engine.
I want to know for sure if the right remedy for this problem is installing a Deep sump kit, or if I should find a different solution. Please help me confirm!
Thanks for your help as always!
Im running Michelin Pilot Sport Cup tires and take the car to the limit. Sadly I think that I would have avoided this problem with a Deep Sump Kit. Yet Im not sure since PCA has articles saying oil starvation is not a problem on the M96 engine.
I want to know for sure if the right remedy for this problem is installing a Deep sump kit, or if I should find a different solution. Please help me confirm!
Thanks for your help as always!
07-13-2017, 12:44 AM
#3
Rennlist Member
FVD pan with baffle at the minimum! + fresh oil.
07-13-2017, 02:20 AM
#4
Hey Moe - first off good luck with the new rebuild. Someone in the 996 forum linked to a really good thread recently but I forget its name. It sounds like a 'fix' for the oiling issues, whether it be aeration, viscosity loss or low pressure. It seems a solution exists but is only available via special order with the racer/engineer that designed the system.
Let me find the thread. Btw - probably want to use an oil that's designed for track use like XP9. You can get away with other oils, but it makes sense to me to use an oil designed for the use. Particularly given that oiling while under stressful operating conditions is a big source of blown engines. My oil can hit ~230F during uphill, low-speed canyon sections.
potentially a big contribution to the m96 tracking community https://rennlist.com/forums/racing-a...mp-system.html
Let me find the thread. Btw - probably want to use an oil that's designed for track use like XP9. You can get away with other oils, but it makes sense to me to use an oil designed for the use. Particularly given that oiling while under stressful operating conditions is a big source of blown engines. My oil can hit ~230F during uphill, low-speed canyon sections.
potentially a big contribution to the m96 tracking community https://rennlist.com/forums/racing-a...mp-system.html
07-13-2017, 09:42 AM
#5
Rennlist Member
07-13-2017, 10:09 AM
#6
Rennlist Member
Lots of interesting explanation and experience here:
https://rennlist.com/forums/996-foru...-pressure.html
Even after reading all of that, I don't think a deep sump and additional or better baffling is a cure, but it may help.
So far, I've learned that the oil pools in the heads and possibly foams so to prevent these or minimize these problems:
1) consider a deep sump and better baffles.
2). Use high temperature racing oil
3). Check that you pan sealant of choice doesn't react adversely with the oil
4). Consider going to the racing spec AOS.
5). Or just get a dry sump metzger engine Porsche......
and it's doubtful 1-4 are an actual fix, and 5 is a wee bit expensive.
https://rennlist.com/forums/996-foru...-pressure.html
Even after reading all of that, I don't think a deep sump and additional or better baffling is a cure, but it may help.
So far, I've learned that the oil pools in the heads and possibly foams so to prevent these or minimize these problems:
1) consider a deep sump and better baffles.
2). Use high temperature racing oil
3). Check that you pan sealant of choice doesn't react adversely with the oil
4). Consider going to the racing spec AOS.
5). Or just get a dry sump metzger engine Porsche......
and it's doubtful 1-4 are an actual fix, and 5 is a wee bit expensive.
07-13-2017, 11:41 AM
#7
From the previously linked thread:
My long experience with various engines leads me to conclude that most of the time, the brand of oil matters very little, and the weight of that oil matters even less. Engines that receive an uninterrupted supply of oil, even at a very low pressure, seem to last forever. Engines that do not, fail regardless of oil brand, weight, or temperature.
That said, everything in racing takes place in that last 1% of performance, so very small things can matter. I use Mobil 1 (the weight depends on expected oil temp) in my dry sump engines, but I don't recommend it for wet sump M96 engines that are used on track.
Chris Cervelli
Cervelli Technical Service
That said, everything in racing takes place in that last 1% of performance, so very small things can matter. I use Mobil 1 (the weight depends on expected oil temp) in my dry sump engines, but I don't recommend it for wet sump M96 engines that are used on track.
Chris Cervelli
Cervelli Technical Service
Trending Topics
07-13-2017, 03:37 PM
#9
Rennlist Member
I'd talk to JR and take his recomendations...
07-13-2017, 04:02 PM
#10
What's been documented so far that I know of:
- Use fresh ~XP9 on track day, change back to your street oil (fresh batch) after the session. If you have a dedicated track car, observe the mileage constraints on the XP9 and use UOAs to monitor hight temp zinc package depletion - doing so will help you determine an oil change interval that is appropriate
- You can limit revs to ~6.5k to prevent unnecessary overheating of the engine oil
- Run oil at half full on dipstick to prevent AOS ingestion & smoking
- Install a standalone oil temp monitor & gauge for relatively little cost. Make sure you're not exceeding the limit of the oil in your
You can also just read his web page that addresses the topic:
http://www.flat6innovations.com/inde...owall=&start=1
a relevant excerpt:
I apologize to Jake if posting this irritates him. Please understand the intent here is to refrain from making stuff up, guessing where others have actually done proper research, and zap these endless cycles of rumination about topics that have been clearly addressed in prior threads and articles.
If this is a technical forum it should be perfectly acceptable and encouraged to compile, share and discuss the public inputs of more enlightened members. I'm a customer and a fan.. there is no intention to undermine or improperly attribute anything that can be construed as negative. We're all here to learn. And, thank you for your contributions. They are appreciated and followed.
- Use fresh ~XP9 on track day, change back to your street oil (fresh batch) after the session. If you have a dedicated track car, observe the mileage constraints on the XP9 and use UOAs to monitor hight temp zinc package depletion - doing so will help you determine an oil change interval that is appropriate
- You can limit revs to ~6.5k to prevent unnecessary overheating of the engine oil
- Run oil at half full on dipstick to prevent AOS ingestion & smoking
- Install a standalone oil temp monitor & gauge for relatively little cost. Make sure you're not exceeding the limit of the oil in your
You can also just read his web page that addresses the topic:
http://www.flat6innovations.com/inde...owall=&start=1
a relevant excerpt:
Remember: Your favorite "flavor" of over the counter generic engine oil might be a 10/40 or 20/50 but it's viscosity is measured at a mere 212F. What will the viscosity of that oil be at 250, 270 or even 290F? What if your 40 grade oil was less than a 20 grade when operating above 260F? Some are!
When operating your engine on the track it is being overworked just like a race engine. This is one of those situations where you need a full "race oil" to properly protect your "street engine". Race oils have a life span of less than 1,000 miles with their additive packages being depleted completely. True race oils make horrible street oils so those that are serious about engine protection aren't generally worried about cost or convenience. These people are paid dividends of longevity and reliability over their peers.
Basically what we have found is G forces are simply "the straw that breaks the Camel's back" on the track. Hot oil leads to pressure losses, G forces aggravate the issue and things scatter.
I won't make brand or viscosity recommendations in this tech article and please don't email me with questions like this. I simply wanted to stimulate your thought before going to the track for another hot summer of track activities~
Those that want to keep their engine alive on the track should couple a proper race oil with higher volume scavenge pumps, better oil control baffles and a higher volume oil filter. All of which LN Engineering and Flat 6 Innovations have teamed up to develop and manufacture.
When operating your engine on the track it is being overworked just like a race engine. This is one of those situations where you need a full "race oil" to properly protect your "street engine". Race oils have a life span of less than 1,000 miles with their additive packages being depleted completely. True race oils make horrible street oils so those that are serious about engine protection aren't generally worried about cost or convenience. These people are paid dividends of longevity and reliability over their peers.
Basically what we have found is G forces are simply "the straw that breaks the Camel's back" on the track. Hot oil leads to pressure losses, G forces aggravate the issue and things scatter.
I won't make brand or viscosity recommendations in this tech article and please don't email me with questions like this. I simply wanted to stimulate your thought before going to the track for another hot summer of track activities~
Those that want to keep their engine alive on the track should couple a proper race oil with higher volume scavenge pumps, better oil control baffles and a higher volume oil filter. All of which LN Engineering and Flat 6 Innovations have teamed up to develop and manufacture.
If this is a technical forum it should be perfectly acceptable and encouraged to compile, share and discuss the public inputs of more enlightened members. I'm a customer and a fan.. there is no intention to undermine or improperly attribute anything that can be construed as negative. We're all here to learn. And, thank you for your contributions. They are appreciated and followed.
07-13-2017, 05:30 PM
#11
Drifting
# 3,6,10 above = excellent summary in my limited but happy experience.
The strange thing is that when we discuss oil starvation/damage, some will dicker based on minimal knowledge or experience . At that stage the smart guys abandon the Thread.Hopefully the sceptics will not notice this helpful Thread.
And good luck with the rebuild ! Hint - always a popular thread to post here -" My M96 Rebuild- take 2 ..."
The strange thing is that when we discuss oil starvation/damage, some will dicker based on minimal knowledge or experience . At that stage the smart guys abandon the Thread.Hopefully the sceptics will not notice this helpful Thread.
And good luck with the rebuild ! Hint - always a popular thread to post here -" My M96 Rebuild- take 2 ..."
07-13-2017, 05:32 PM
#12
Former Vendor
These engines have problems with overloaded, overheated oil. This breeds the issues that appear to be G force rooted, when the G forces only push things over the edge.
Failure of the #6 rod bearing comes from failure of the aft main bearing, as the oil that feeds #6 is delivered to it as waste oil from the aft main bearing. The oil is fed to the rod bearing primarily through centrifugal force.
On the track use of the clutch up and down through the gearbox creates a ton of heat at the aft portion of the crankshaft. This heat is transferred to the main bearing journal closest to the flywheel, which is ironically the same main bearing thats delivering oil to the #6 rod bearing.
This heat creates a condition where the oil shears. Once the oil shears, wear increases. When the aft main bearing begins to wear, foreign object debris from this wear is generated. Once the debris is generated, it is then force fed into the #6 rod bearing, creating a rod bearing failure, leading to a connecting rod bolt failure, and total engine loss.
This is not new. I have seen it hundreds of times. This lands 50% of our work here, and I have been researching this since day #1.
Use an oil proven to maintain viscosity at 300 degrees F. The only oils I have seen do this are Driven
XP6,7 & 9, or Motul 300V. Nothing else.
That said, the true "fix" for this comes in the form of altered running clearances for the components, to reduce the shear, as well as protective coatings to help gain some margin of error. Not sure if the F1 engine builder opened the clearances, or not- If I built it, they would have been.
Failure of the #6 rod bearing comes from failure of the aft main bearing, as the oil that feeds #6 is delivered to it as waste oil from the aft main bearing. The oil is fed to the rod bearing primarily through centrifugal force.
On the track use of the clutch up and down through the gearbox creates a ton of heat at the aft portion of the crankshaft. This heat is transferred to the main bearing journal closest to the flywheel, which is ironically the same main bearing thats delivering oil to the #6 rod bearing.
This heat creates a condition where the oil shears. Once the oil shears, wear increases. When the aft main bearing begins to wear, foreign object debris from this wear is generated. Once the debris is generated, it is then force fed into the #6 rod bearing, creating a rod bearing failure, leading to a connecting rod bolt failure, and total engine loss.
This is not new. I have seen it hundreds of times. This lands 50% of our work here, and I have been researching this since day #1.
Use an oil proven to maintain viscosity at 300 degrees F. The only oils I have seen do this are Driven
XP6,7 & 9, or Motul 300V. Nothing else.
That said, the true "fix" for this comes in the form of altered running clearances for the components, to reduce the shear, as well as protective coatings to help gain some margin of error. Not sure if the F1 engine builder opened the clearances, or not- If I built it, they would have been.
07-13-2017, 06:24 PM
#13
Hi Jake - Curious if you've had any interaction with Chris Cervelli. In his thread linked above, he notes running 5,000 track hours on his dry sump system & finally overcoming a continuous cycle of on-track failures.
From reading about the stellar track record of both your engines and his dry sump system, it sounds like there are two paths to get to the coveted 'reliably trackable' m96 platform. Combining the two seems like it could offer an incredibly robust system to both improve internal construction and ensure lubrication is less susceptible to the heating processes you note.
From my perspective, there's enough gap between the GT3 & m96 markets to support such a combined system. Of course, a question like this underlines the wide gulf that exists between saying something and getting it done. Just curious if it's something you think about, or if you don't think it's necessary.
From reading about the stellar track record of both your engines and his dry sump system, it sounds like there are two paths to get to the coveted 'reliably trackable' m96 platform. Combining the two seems like it could offer an incredibly robust system to both improve internal construction and ensure lubrication is less susceptible to the heating processes you note.
From my perspective, there's enough gap between the GT3 & m96 markets to support such a combined system. Of course, a question like this underlines the wide gulf that exists between saying something and getting it done. Just curious if it's something you think about, or if you don't think it's necessary.
07-13-2017, 06:53 PM
#14
Rennlist Member
07-13-2017, 11:00 PM
#15
Rennlist Member
Thread Starter
Thanks for the help. I was using fresh Motul 8100 X-Cess oil. I dont get Joe Gibbs oil here but I can buy Motul 300V. So will a deep sump help? I was considering buying the LN Engineering kit. From what I can tell from reading the above it would benefit from using a deeper sump as well as Motul 300V.