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Engine Specific Info and Questions => IDI Engine => Topic started by: haybayian on February 06, 2008, 01:12:16 pm
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I am considering setting up an electric pump on my T3 turbo's oil return line. Do you have any advice for me? At this point all I know is that a gear pump is a must (as opposed to a diaphragm one) and that I should be prepared to pay between 175 $ (Summit) and 230$ elsewhere.
Haybayian
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Will it work when cooling down,or will it be cycling all the time?
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gear pumps are positive displacement which means whatever goes into them, has to come out. So if it fails your turbo is going to be junk.
Why are you wanting to add one?
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scavenge oil from the turbo return line? hmmm... hope it likes sucking in air once in a while :lol:
EMP was designing an electric oil pump a while ago.. never heard too much since (it was going to be a really durable oil pump... that could take over the job of the main oil pump... good for priming the engine before starts, turbo cooldown, etc :wink:)
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Will it work when cooling down,or will it be cycling all the time?
I was thinking full time use but mainly when the turbine is spooling on with little or no oil after the engine has been turned off.
Perhaps a rotodynamic pump (centrigugal for instance) instead of positive displacement, working only shortly before and after the engine has been turned off would be a better idea????
Haybayian
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So, is the idea to promote turbo longevity?
One thing to keep in mind is that the return lines on these cars are large enough to handle the amount of oil coming into / out of the turbo. If you sludge it, thats a different story. Also, most of the factory turbos go for well over 100k miles with no problems when the right oil is used and OCI's are observed.
Point being - there really isn't a longevity issue with the turbos on these cars.. also they don't run near as hot as cars that eat turbos alot (ie. heavy passat / a4 1.8t)
In my experience heat and sludging are the ultimate turbo killers.
If you were pushing tons of boost the situation might vary a bit, but I think if you were running a high grade synthetic 5w40 oil like pentosin, elf, Rotella syn or the like.. I think you'd be fine.. There are plenty of folks around here running insane boost and pushing near meltdown egt's that have few turbo problems.
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Will it work when cooling down,or will it be cycling all the time?
I was thinking full time use but mainly when the turbine is spooling on with little or no oil after the engine has been turned off.
Perhaps a rotodynamic pump (centrigugal for instance) instead of positive displacement, working only shortly before and after the engine has been turned off would be a better idea????
Haybayian
I'm thinking your theory may be flawed. You will be sucking out of the supply side of the engine. As soon as you suck the oil, you are draining the engine oil passages(engine off), and as soon as the head drains, you will be sucking air. You won't be sucking it out of the pan.
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quote:I'm thinking your theory may be flawed. You will be sucking out of the supply side of the engine. As soon as you suck the oil, you are draining the engine oil passages(engine off), and as soon as the head drains, you will be sucking air. You won't be sucking it out of the pan.[/quote]
Not the right place to suck oil indeed. Or perhaps there should be a separate intake plumbing in the pan. VERYYYYYyyyyyy complicated!!! :lol:
Interestingly judging from the responses here VW diesels dont have turbo lubrication problems.
Thanks for all the contributions.
Haybayian
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You will be sucking out of the supply side of the engine. As soon as you suck the oil, you are draining the engine oil passages(engine off), and as soon as the head drains, you will be sucking air. You won't be sucking it out of the pan.
Good catch... this means your turbo will start the next time *without* oil because the line is empty. Ack !!
Haybayian: my guess is that your question is related to your other thread on oil filter relocation ???
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The only way I could see it working, which would require a remote filter, would be to put a check valve after the filter but before the engine, and have your pump suck from between the filter and check valve. I would then plumb it in PARALLEL to the turbo oil feed, probably as close to the turbo as possible. That way the pump wouldn't interfere with normal oiling if it failed, would possibly supplement normal oiling if it made enough pressure, and could be run before or after starting. It would probably send oil to the bearings as well, so would eliminate dry starts.
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Some heavy equipment has 2 starters, the first one drives an oil pump and the second is not activated until an oil pressure sensor in the head indicates that there is oil pressure present. I was thinking of adapting something similar to my car but have not looked into it enough
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Then again, an accumulator or two, one for starts, one to oil at engine shutoff, might be a lot easier to install.
Here you go in fact. http://www.accusump.com/acc_products/acc_turboiler.htm
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Haybayian: my guess is that your question is related to your other thread on oil filter relocation ???[/quote]
Yes I am in oil things up to my neck.
Haybayian
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Well come on... tell us the details... inquiring minds want to know !!!
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Well come on... tell us the details... inquiring minds want to know !!!
Well not much to write home about!
I am building a sportscar (Lotus 7) from scratch and my choice of engine was the AAZ. I had the engine rebuilt (long block) by a shop in Toronto and the VE pump was rebuilt by Giles with performance mods. I did not ask what he was going to do. He got me a T3 Garrett and manif. I built my own exhaust line from the turbo to the muffler in 3 " pipes. The VW engine was bolted to a Suzuki Samurai 5 speed transmission which I owned through an adapter sold by ACME in the US .
Currently I am sweating the engine details. The oil filter ended up too close to my home made engine support bracket so I have bought a kit to relocate it. I am ignoring the VW water/oil cooler and setting up a larger air oil cooler. As my car will be a Summer car only I think that this will work. As I was ordering a T3 oil return line I read a bit about turbos and learned that the racing crowd often equip their turbos with oil pumps in an attempt to save their bearings from running too hot or dry in some circumstances. As you can gather from my questions there are still a few things that I don't quite understand but I will keep reading.
I am grateful for the advice that you guys are giving me on this forum.
Haybayian
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The only way I could see it working, which would require a remote filter, would be to put a check valve after the filter but before the engine, and have your pump suck from between the filter and check valve. I would then plumb it in PARALLEL to the turbo oil feed, probably as close to the turbo as possible. That way the pump wouldn't interfere with normal oiling if it failed, would possibly supplement normal oiling if it made enough pressure, and could be run before or after starting. It would probably send oil to the bearings as well, so would eliminate dry starts.
If I was fanatical enough to set up a special oiling system for my turbo I think that I would leave the engine lubrication system alone and set up a separate oil can, filter , pump and cooler for the turbo, totally independent.
So far I gather that no one here believes that the turbo on a VW needs special attention. For the time being I am going to leave it at that.
Haybayian.
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I am building a sportscar (Lotus 7) from scratch and my choice of engine was the AAZ. I had the engine rebuilt (long block) by a shop in Toronto and the VE pump was rebuilt by Giles with performance mods. I did not ask what he was going to do. He got me a T3 Garrett and manif. I built my own exhaust line from the turbo to the muffler in 3 " pipes. The VW engine was bolted to a Suzuki Samurai 5 speed transmission which I owned through an adapter sold by ACME in the US .
Currently I am sweating the engine details. The oil filter ended up too close to my home made engine support bracket so I have bought a kit to relocate it. I am ignoring the VW water/oil cooler and setting up a larger air oil cooler. As my car will be a Summer car only I think that this will work. As I was ordering a T3 oil return line I read a bit about turbos and learned that the racing crowd often equip their turbos with oil pumps in an attempt to save their bearings from running too hot or dry in some circumstances. As you can gather from my questions there are still a few things that I don't quite understand but I will keep reading.
I am grateful for the advice that you guys are giving me on this forum.
Haybayian
I have a friend who did that, though since he works on Miatas, he put a 160 hp Miata engine in it. I was thinking it would have been cool with a Diesel. Guess you did too. :twisted:
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the turbo could benefit from a turbo timer.
i'm going to use amsoil's oiler. its an accumulator that is basically plug n play. when the ignition is on it releases the oil pressure to 'prime' the engine. a little bit expensive at $400 but it would go a long way to keeping that engine fresh :wink:
seperate oiling for the turbo would be neat... with its own oil cooler as well. turbo's like to run thin oils right? this would make that possible.
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the turbo could benefit from a turbo timer.
i'm going to use amsoil's oiler. its an accumulator that is basically plug n play. when the ignition is on it releases the oil pressure to 'prime' the engine. a little bit expensive at $400 but it would go a long way to keeping that engine fresh :wink:
seperate oiling for the turbo would be neat... with its own oil cooler as well. turbo's like to run thin oils right? this would make that possible.
Glad to see that someone else is thinking about turbo lubrication.
What I think is that a completely independent turbo lubricating system would provide (as you mentionned) the ability to use a different oil; synthetic oil designed for very high speed rotation and hot temperature. A separate positive displacement pump would provide the turbo with a constant oil flow which is not the case with the engine's mechanical pump. A separate cooler and filter could also be gauged to the turbo's needs instead of the whole engine. Such a system should be equiped with a pressure/heat sensor and automatic shutoff to save the turbo if the electric pump was going to fail. By-the-way, the system that I am outlining would probably cost less than $400.
Maybe one day I will look into that. For now I have other priorities.
Haybayian.
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Not exactly a completely seperate oiling system for the turbo, but an interesting idea nonetheless, is the "APLS" system (used to be sold as the "Cardiolube").
It's an electronic pre-oiler AND post-oiler. Accusump is only a pre-oiler. This thing can be rigged to continue to flow the oil until a set time (or temperature) AFTER engine shutdown.
So it's like a turbo-timer after shutdown, except it doesn't leave your engine idling (it just kills your battery!) And the next time you start your engine, it spools up its pump so you have oil pressure before starting.
www.wetstart.com
(http://www.wetstart.com/images/aplsSchematicLarge.jpg)
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This sounds like a brilliant idea, a true sports car that is fun to drive. I would encourage you to keep it as simple as possible, unless you like working on it more than driving. I was trying to figure out if you were referring to a dry sump oil scavenge pump as this is common on real race engines. Dry sumps are used to reduce engine frictional losses by keeping the crank from whipping the oil to a froth by removing it to a separate oil reservoir. If there is inadequate oil drainage from the turbo bearings the trapped oil in the bearing cartridge will start to leak past the turbo seals so possibly a scavenge pump might help there as in a vanagon td setup where the oil drain is almost horizontal. From what I have seen the oil accumulator systems and prelube pumps are solutions to a problem of excess money in your pocket. The VW turbos in near stock configuration are quite durable and well designed. The guys with the Skylines and hopped up Hondas are going to blow up their motors & turbos whether they have prelube systems , turbo timers , or accumulators it's what they like to do. Just my opinion. Cheers Dan
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engine pre-lube is a great idea. if you start your car with the clutch depressed it puts a lot of load on the thrust bearing since there is no oil pressure.. with an accumulator you can 'virtually' eliminate this problem. and maybe squeeze more life out of the engine :wink:
i'm definitely going with amsoil's system though... it's pretty much plug n play with minimal installation requirements.