Possible oil pickup tube solution

So this pickup tube issue has been on my mind lately. I know that the Killer B tube is a solution, but at $200+, I figured there had to be a less expensive way to solve it. I have a bunch of STI pickup tubes laying around and was thinking about doing this to them. Here is a crude drawing of what I have in mind. The black represents the stock pickup tube, the red is a short but robust metal sleeve to go over the tube, and the green is where the sleeve would get welded on. This would just involve cutting the tube at the flange, sliding the sleeve on, and welding.

http://img708.imageshack.us/img708/8561/pickupsolution.png

I've seen dozens of pictures of failed pickup tubes, and all of them failed in the area that the sleeve would cover. Can anyone think of any drawbacks to doing this or reliability problems? I plan on mocking one up soon so we can see what it would look like in action.

You will just move the problem down the sleeve.

Welding will in addition to that add a material change that makes it more sensitive to cracking.

Judging by the assessment that killerb made:

The cause it braze flux left on the tube after brazing. The braze etches into the weld seam of the tube. If you do some research on brazing and/or welding you'll find leaving any leftover braze flux after brazing is a big no no.

 

Engine vibration, state of tune, modifications have less to do with it than you'd think. What does induce a significant amount of vibrations/harmonics is the high frequency hydrailic hammering from the oil pump.

 

There is no TSB on the oil pickup. There is one out there for the turbo supply lines, but that is not related to the pickup.

It seems like this problem will only happen at or near the flange where the excess flux is. I've never seen any tube have a problem where the bend begins.

Stick with the stock one, the odds are heavily weighted in favour of it lasting.

I dunno man. I've seen a bunch of failed tubes on completely stock cars.

Welding is little more than taking a perfectly good material microstructure, and ruining it.

I think your best bet would be to get a KB one, or get a Covert one for less money. I like the KB one, but truthfully only got one because it was a great deal (from KTMRider on the board, at a price I'd rather not disclose due to fear of being robbed).

I'll do the install when I find some time. It's a painful process if the engine is still in the car. Since the KB meets and exceeds OEM design, I am fairly certain it won't alter vehicle warranty. Same goes for their windage tray.

I dunno man. I've seen a bunch of failed tubes on completely stock cars.

 

Welding is little more than taking a perfectly good material microstructure, and ruining it.

 

I think your best bet would be to get a KB one, or get a Covert one for less money. I like the KB one, but truthfully only got one because it was a great deal (from KTMRider on the board, at a price I'd rather not disclose due to fear of being robbed).

 

I'll do the install when I find some time. It's a painful process if the engine is still in the car. Since the KB meets and exceeds OEM design, I am fairly certain it won't alter vehicle warranty. Same goes for their windage tray.

I don't want to get into the whole thing again, done that too many times in other threads, but just look at the statistics.

There is a greater chance of being in a traffic accident than having the stock pick up fail.

Nice flawed logic there

YOUR CAR IS DOOMED!!!!!!!!!!!!1111!!1!1111

Nice flawed logic there

 

YOUR CAR IS DOOMED!!!!!!!!!!!!1111!!1!1111

Any logic is better than none

My car is safe and sound at home, haven't driven it for 3 months, and I doubt it will even start anymore. At least I know the oil pick up isn't going to fail though.

I don't want to get into the whole thing again, done that too many times in other threads, but just look at the statistics.

 

There is a greater chance of being in a traffic accident than having the stock pick up fail.

I don't disagree. I'm just saying I've seen it a bunch of times.

If you are rebuilding an engine, or want piece of mind, I can't see not picking up an improved pickup. Certainly isn't going to hurt anything. I probably would not have bought one, but I got it with the windage tray for not much more than a song.

I think you need a more rare statistic if you want to really play up the unlikelihood of failure. According to the NHTSA, you have a 30% chance of being involved in a serious automobile accident in your driving lifetime. Like the odds that you'll drown in a bathtub (~685,000:1).

Stick with the stock one, the odds are heavily weighted in favour of it lasting...I don't want to get into the whole thing again, done that too many times in other threads, but just look at the statistics. There is a greater chance of being in a traffic accident than having the stock pick up fail.

Just because a pickup tube continues to "function" does not mean anything. My pickup tube had TWO bad cracks in it but continued to function when we dropped my oil pan. It is a fact that I am very lucky not to have lost a motor. IMO all LGT need their pickup replaced for peace of mind and the banjo bolt filters removed. I promised myself if I ever dropped the pan I'd replaced it and I did. Dont/can't regret it a bit.

IMPO, the reason the stock pickup tubes fail is this;

When you install a new pickup, you attach the flange to the oil pump and torque it down. There is a support bracket that bolts to one of the windage tray attachment bolts. To get this bracket bolted down the entire tube has to be slightly bent unless you shim under the bracket. I used an OE pickup on my rebuild. I just shimmed the bracket so the tube isn't being stressed.

Added a poll to see the general feeling.

GTTuner: So are you saying that the two mounting locations for the pickup tube aren't on the same plane? Does the killerb tube have staggered mounting locations to accommodate for this or is the material just sturdy enough to withstand the bending?

IMPO, the reason the stock pickup tubes fail is this;

 

When you install a new pickup, you attach the flange to the oil pump and torque it down. There is a support bracket that bolts to one of the windage tray attachment bolts. To get this bracket bolted down the entire tube has to be slightly bent unless you shim under the bracket. I used an OE pickup on my rebuild. I just shimmed the bracket so the tube isn't being stressed.

now that is interesting. what do you think of the heat aspect? many of the failures i've seen pics of look to me to have not been liking the heat cycling on that end; perhaps a different (less conductive) gasket would throw the odds down to something closer to astronomical?

Heat, vibration, pre-tension and add to that changes to the metal structure when the end was brazed all contributes to metal fatigue. Flux used at the brazing may play some role too, but it is quickly consumed during the brazing and only acts on the surface of the material.

As for the quiz - it's not a silly idea, but as I stated before - the sleeve will just move the problem.

Heat, vibration, pre-tension and add to that changes to the metal structure when the end was brazed all contributes to metal fatigue. Flux used at the brazing may play some role too, but it is quickly consumed during the brazing and only acts on the surface of the material.

 

As for the quiz - it's not a silly idea, but as I stated before - the sleeve will just move the problem.

This is pretty right on.

There isn't any sufficient change to microstructure when something is correctly brazed. Brazing is more like soldering at higher temps. You'd have to be brazing for more than 35 seconds to even have an impact on the microstructure. But the tube is in tension, it's poorly supported, and you get loads of vibration. The impact of vibration only increases as suspension stiffness increases, and engine mount stiffness increases.

Heat isn't a huge contributing factor, though. Again, we are talking about relatively low temperatures when it comes to steel. Average oil temperatures almost never exceed 100C. You could hold steel at 100C for, almost literally, forever without having any impact on microstructure.

If you weld on top of what is already there, you will probably experience more problems than you solve. I bet, if you tried this, you'd almost definitely get failure of the tube. The correct way to fix the problem, is a newly designed pickup. KillerB did it already, Covert knocked it off. If you are going to pull the pan to replace the pickup, what's the problem spending a few extra bucks over a modified one, for a new one better suited to handling the stress?

I think this is fixing a problem that doesn't exist.

Ever think that maybe the oil you are using is reacting with the braze flux and that is what is causing the failure? I heard that Mobil 1 doesn't react with flux.

Ever think that maybe the oil you are using is reacting with the braze flux and that is what is causing the failure? I heard that Mobil 1 doesn't react with flux.

Royal Purple definitely does.

now that is interesting. what do you think of the heat aspect? many of the failures i've seen pics of look to me to have not been liking the heat cycling on that end; perhaps a different (less conductive) gasket would throw the odds down to something closer to astronomical?

The tube looks burnt up and blue brand new out of the package.

If I remember correctly, Subaru released a recall for some turbo oil feed pipes that developed cracks. That recall covered cars beginning in 2007.

To my knowledge, they haven't released a recall for any pickup tube failures, which, to my knowledge, that part hasn't changed since 2005.

Added a poll to see the general feeling.

 

GTTuner: So are you saying that the two mounting locations for the pickup tube aren't on the same plane? Does the killerb tube have staggered mounting locations to accommodate for this or is the material just sturdy enough to withstand the bending?

The support bracket on the OE tube never lines up, I shim them so the tube isn't "stressed" once tightend down.

The KB pickup comes with a different windage tray. The pick-up fits precisely as it should. You could flip the motor upside down and pick it up bt that KB unit. It's beefy.

The support bracket on the OE tube never lines up, I shim them so the tube isn't "stressed" once tightend down.

 

The KB pickup comes with a different windage tray. The pick-up fits precisely as it should. You could flip the motor upside down and pick it up bt that KB unit. It's beefy.

You are definitely stronger than me if you can pick up a longblock bare-handed!

But you are right, beefy it is. Bolt it down, and you could easily stand on it.