Major oil leak
02-24-2005, 06:32 PM
#46
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Oh Boy...
i read that thread jmreiser and I have not got a clue what you said. 
But here is my plan. DRIVE THE CAR.
I have new turbos right from Germany. What else can I do. The way my motot was built, I have to assume everything is OK. Smoke for a few seconds and then nothing.
Right?
But here is my plan. DRIVE THE CAR.
I have new turbos right from Germany. What else can I do. The way my motot was built, I have to assume everything is OK. Smoke for a few seconds and then nothing.
Right?
02-26-2005, 01:14 AM
#48
Three Wheelin'
Hi Joel. I've read your exerpt on the PCA tech site about how you have re-engineered the plumming to divert excess oil back into the crank case, alleviating engorged, oil filled turbos. Can you go more into depth how you accomplished this? I think I like the re-route better than check valves and I'd like to do this to my car. How do I do this??
Jaime
If anybody else know please feel free to chime in.
Jaime
If anybody else know please feel free to chime in.
02-26-2005, 04:49 PM
#49
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The angle on the oil consumption that is based on the fact that there is to much oil flowing through the bearing housing is wrong.. The K16's or K24 turbochargers needs oil flow to reduce the amount of heat built up from the turbine housing. Another words the turbo need the given amount of oil that is flowing through the turbo to provide lubrication AND heat tranfer.. thus oil is used to reduce the heat by cooling the turbine wheel. Infact I wish that there was more flow to the bearings, and on my higher stage turbochargers I drill the orfice diameter larger this supplies more cooling oil to the turbine wheel and seal area. The 996TT check valve does not reduce the flow, I have pulled one apart and the design basically has a check ball to reduce the oil from siphoning back up the oil supply line once the car has been shut off.. Another words the ball is forced against it's seat only when the car is shut off, and closes the transfer of oil back up into the cam housings. Again we have two seperate topics and two seperate views.. The position or view that the vent line is filling up as a excape route due to the lack of scavenge from the scavenge pump is incorrect.. The size of the 3 gears and volume that this little pump can handle exceeds the oil coming into the very small inlet oil lines.. The most crutial time is a idle and when the oil is cold.. I have taken the vent lines off the sump pumps on many cars including my own!! I installed a bent standpipe with 2.5 inches of height to simulate the oil level of the turbo turbine housing. Guess what, there is/was no oil flowing out of the sump Vent line at any time when these lines are removed.. As I have mentioned in earlier posts, if a race engine has blow by of any sort, you will have a situation of High base pressure.. Many PCA racers will accept higher leakdown numbers and run the car, vs a scheduled rebuild. This will definately cause oil to blow through the vent lines. feels that the oil is being overflowed while the car is running!!
Most Rennlister's have complained about startup smoke, on either tail pipe.. If oil was in the center plenum (alledged vent line problems), Your engine will be smoking from both tailpipes because oil will be entering both sides of each engine bank. The oil isn't going to say, well I just run down on the left bank of the engine and then smoke out the right tailpipe.. Also, you will not see oil puddling under your engine, specifically under the turbochargers. The Porsche scavenge pump is not at fault.. Many owners have emailed me and told me that there mechanics have wanted to replace the Pcar scavenge pump... because they have read the it is a scavenge issue.. This is NOT the case for a street 993TT.. If someone is using Garrett turbochargers, Garrett's do not like the volume of oil & Pressure that the Pcar supplies.. A restriction is often advised, however, again I do not recommend this.. Instead I install KKK style bearings in the Garrett's to make them live..
If scavenging was the issue these cars would have never made it 5000 miles back in 1996 when new.. I'm stating for the record that the scavenge pump is not the issue, nor the vent lines, for a street 993TT, this includes 99% of cars driven at DE events. The oil is coming from only 2 issues.. Faulty turbocharger seals, or high oil levels that occur in the sumps. This is caused by oil siphoning back up the oil supply/feed lines. This can be solved by installing the 996TT check valves. However, this isn't the root cause.. The cause is the sump tanks to sump pump oil lines.. These lines backfill oil from the engine to the sump tanks, the oil level increases above the turbo seals.. And since the seals have been worn through mileage and abuse (hot shutdowns).. oil passes through these seals.. On start up the oil that is in the turbine housing immediately appears as smoke on start up. The oil that has leaked out of the compressor wheels gets pushed from boost pressure into the intercooler and into the center plenum and back into the engine..
Again oil is migrating from the engine case to the turbo's.. I was at Andial this week, and they have a good solution to stop this oil transfer.. However, I recommend both options, the 996TT check valves and the sump-sump pump lines (these are not vent lines) I must strongly state that none of these fixes will hold the oil level in check if you have a faulty oil filter!! and or high oil levels..
Most Rennlister's have complained about startup smoke, on either tail pipe.. If oil was in the center plenum (alledged vent line problems), Your engine will be smoking from both tailpipes because oil will be entering both sides of each engine bank. The oil isn't going to say, well I just run down on the left bank of the engine and then smoke out the right tailpipe.. Also, you will not see oil puddling under your engine, specifically under the turbochargers. The Porsche scavenge pump is not at fault.. Many owners have emailed me and told me that there mechanics have wanted to replace the Pcar scavenge pump... because they have read the it is a scavenge issue.. This is NOT the case for a street 993TT.. If someone is using Garrett turbochargers, Garrett's do not like the volume of oil & Pressure that the Pcar supplies.. A restriction is often advised, however, again I do not recommend this.. Instead I install KKK style bearings in the Garrett's to make them live..
If scavenging was the issue these cars would have never made it 5000 miles back in 1996 when new.. I'm stating for the record that the scavenge pump is not the issue, nor the vent lines, for a street 993TT, this includes 99% of cars driven at DE events. The oil is coming from only 2 issues.. Faulty turbocharger seals, or high oil levels that occur in the sumps. This is caused by oil siphoning back up the oil supply/feed lines. This can be solved by installing the 996TT check valves. However, this isn't the root cause.. The cause is the sump tanks to sump pump oil lines.. These lines backfill oil from the engine to the sump tanks, the oil level increases above the turbo seals.. And since the seals have been worn through mileage and abuse (hot shutdowns).. oil passes through these seals.. On start up the oil that is in the turbine housing immediately appears as smoke on start up. The oil that has leaked out of the compressor wheels gets pushed from boost pressure into the intercooler and into the center plenum and back into the engine..
Again oil is migrating from the engine case to the turbo's.. I was at Andial this week, and they have a good solution to stop this oil transfer.. However, I recommend both options, the 996TT check valves and the sump-sump pump lines (these are not vent lines) I must strongly state that none of these fixes will hold the oil level in check if you have a faulty oil filter!! and or high oil levels..
02-26-2005, 04:57 PM
#51
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Just in case you haven't heard it enough...THANKS KEVIN for sharing your knowledge....Someday soon unless I steal them out of CJ's poor, neglected, car which is sitting alone again all weekend...
