Oh Bu**er another 2/6 failure?
#16
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Agreed. Moil One is race proven, and used every day in thousands of race and other high-stress applications. It is easy to blame Mobil One, or the tooth fairy, or the gear ratio for 2/6 failure, but ultimately the answer is very elementary ..... BAD ENGINEERING. And the solution is equally simple .... ACCUSUMP. While an accusump (sp?) does not SOLVE the problem, it WORKS AROUND it with 100% success rate, at a cost of a whopping 300 dollars.
Originally Posted by H2
I don't want to rekindle the debate on oil (no-win) but I can't envision the type of oil one uses as contributing significantly to the elimination of 2/6 failure ...
#19
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Well th engine is ready for a lift in the morning, all disconnected and just sat in the engine bay.
Things found so far:
1. cam timing still spot on
2. oil is filthy/black only been in for about 300 miles
3. small amount or shiny material on drain plug:
The oil was a Comma semi synthetic 10/40, oil and filter changed 4 days ago. Car has always been on this oil (4 years) and completed two previous track days.
Yes the rev limiter had been hit, but only in pit straight. Although high revs held aroung both left and right turns (5K) some times.
john
Things found so far:
1. cam timing still spot on
2. oil is filthy/black only been in for about 300 miles
3. small amount or shiny material on drain plug:
The oil was a Comma semi synthetic 10/40, oil and filter changed 4 days ago. Car has always been on this oil (4 years) and completed two previous track days.
Yes the rev limiter had been hit, but only in pit straight. Although high revs held aroung both left and right turns (5K) some times.
john
Last edited by johnb; 12-28-2007 at 11:37 AM.
#20
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Originally Posted by heinrich
Nick the only one I know of was Don Hanson, and his was as a result of off-track and a severed oil feed line?
The racer I bought from Constantine is suspect of having the same failure and was running an accusump also.
#21
Race Car
Originally Posted by drnick
i think there have been 2/6 failures with an accusump installed.
Originally Posted by johnb
Things found so far:
2. oil is filthy/black only been in for about 300 miles
2. oil is filthy/black only been in for about 300 miles
The oil was a Comma semi synthetic 10/40, oil and filter changed 4 days ago. Car has always been on this oil (4 years) and completed two previous track days.
#22
Under the Lift
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Originally Posted by heinrich
Nick the only one I know of was Don Hanson, and his was as a result of off-track and a severed oil feed line?
#23
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I change the oil every 3000 miles, I have done 22,000 miles in the car since I have owned it.
So I have probably changed the oil and filter about 7 times, there has NEVER been any hint of debris on the magnetic drain plug.
I had recently fitted a new sump gasket, and the sump was sparkly clean with absolutely no evidence of any debris.
The crank, and all its journals showed, showed no heat damage at that time. End play was well within spec.
So i am fairly certain that the damage was caused yesterday and was not on going.
I will cut the filter tomorrow and let you know what I find.
John
So I have probably changed the oil and filter about 7 times, there has NEVER been any hint of debris on the magnetic drain plug.
I had recently fitted a new sump gasket, and the sump was sparkly clean with absolutely no evidence of any debris.
The crank, and all its journals showed, showed no heat damage at that time. End play was well within spec.
So i am fairly certain that the damage was caused yesterday and was not on going.
I will cut the filter tomorrow and let you know what I find.
John
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Forgot to say, the engine turns over quite easily with a socket and breaker bar on the pulley bolt. I had to rotate the engine to remove the clutch.
Does anyone know why the engine ran so rough, I appreciate it would have bearing damage, but why rough running? especially as it shows no sign of any tight spot when turned over by hand.
Also the rev counter stopped working as soon as I lost oil pressure, all other instruments fine, well - oil presure reading low !!!
John
Does anyone know why the engine ran so rough, I appreciate it would have bearing damage, but why rough running? especially as it shows no sign of any tight spot when turned over by hand.
Also the rev counter stopped working as soon as I lost oil pressure, all other instruments fine, well - oil presure reading low !!!
John
#27
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amen!
mk
mk
Originally Posted by Jim bailey - 928 International
You can not drive hard enough fast enough on the street without being dead or going to jail....
#28
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dont take it apart. we have a brand new 4.7 ready to go, and its a euro S as well. barely been broken in, 250rwhp with LJet running it. sitting on a pallet ready to ship.
the cheap route would use a set of rods and crank, that also has the larger oiling holes. both from the same, well running street engine.
Let me know if you are interested.
rods and crank $300
almost brand new euro 4.7 , $1500
mk
the cheap route would use a set of rods and crank, that also has the larger oiling holes. both from the same, well running street engine.
Let me know if you are interested.
rods and crank $300
almost brand new euro 4.7 , $1500
mk
Originally Posted by drnick
john, the 2/6 failure sucks, i wonder if its possible to salvage the crank and rods? i know paul anderson has installed th IJ scrapers in his current race engine and so far has not had any problems or used any oil this season. his car is in race winning form and was faster round castle combe than the 996 GT3 rs that was there, this setup might be the ticket... but im already embarked down the drysump route.
the orange car is fast in a straight line btw its just the corners in between i have trouble with there were a few fast cars at the track yesterday, im sure you were not one of the ones holding us up eh?!
the orange car is fast in a straight line btw its just the corners in between i have trouble with there were a few fast cars at the track yesterday, im sure you were not one of the ones holding us up eh?!
#29
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key term is "thousands" (in other types) of race cars.
the 928 either is very sensitive to viscosity break down or foaming. either way, its cheap insurance to use the oil that some uses and has more racing miles on it without failure than any 928 in the world, by a factor of 2 minimum!
redline or amzoil seems to work the best.
and as was mentioned, there has been a few failures with accusump as well. I think the drilling is the most effective fix, but dont discount the oil quality and characteristics at 280F temps, where most engines never see this kind of temps, nor do most other race cars that i see at the track (BMWs for example are 220 to 250F max)
mk
the 928 either is very sensitive to viscosity break down or foaming. either way, its cheap insurance to use the oil that some uses and has more racing miles on it without failure than any 928 in the world, by a factor of 2 minimum!
redline or amzoil seems to work the best.
and as was mentioned, there has been a few failures with accusump as well. I think the drilling is the most effective fix, but dont discount the oil quality and characteristics at 280F temps, where most engines never see this kind of temps, nor do most other race cars that i see at the track (BMWs for example are 220 to 250F max)
mk
Originally Posted by heinrich
Agreed. Moil One is race proven, and used every day in thousands of race and other high-stress applications. It is easy to blame Mobil One, or the tooth fairy, or the gear ratio for 2/6 failure, but ultimately the answer is very elementary ..... BAD ENGINEERING. And the solution is equally simple .... ACCUSUMP. While an accusump (sp?) does not SOLVE the problem, it WORKS AROUND it with 100% success rate, at a cost of a whopping 300 dollars.
#30
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Originally Posted by H2
Has anyone ever had a documented 2/6 failure while running Amsoil?).
I believe David Lloyd has had at least 1 and perhaps as many as 3 with Amsoil.