!! Help with MBC !!

[wishnfor4g63T]

Okay so i've hit just about every thread on here related to mine and i've done everything listed. It's hard to say if i have missed a few threads so Please read my problem and give me an answer!!! i'll send you a Happy Meal!

...So i Have 2 MBC's one off ebay which had worked fine with my T-25 and another from a friend that looks like a Joe P. Regaurdless of where i install the mbc (to the bov or J pipe) i still get 10 PSI. Running the wastegate freely gave it the wonderfull 30 pounds and up on the boost gauge so i know the wastegate is not stuck.

I'm starting to have this feeling i'm going to have to drill the turbo like the t-25 and tap it. As far as i'm concerned if that means it will work i'll do it . BTW i don't know if this is a dumb thing to add but when i tapped my J pipe i left half the tubing in the pipe so it's like half in the pipe and half sticking out so i could put the hose on the end. I didn't know if this would make it hard to get the air to the MBC but maybe i just answered my own theory. What doesn't make sense is that the BOV line boosts to 10 also with a lil spike.

Well if anyone can help or has had the same problem i would greatly appreciate it. BTW this is a Slowboys Big 16g ported and polished with bigger turbine. I still have around 10 more days of warranty on it so i can send it back if anyone thinks it's turbo related. Thanks for any and all help!

 

[98mitsuGSX-SD]

So you drilled into the J-pipe and didn't tap it for a 1/8 NPT barb fitting and just stuck a portion of hose into the drilled hole? And you disconnected the vaccum wastegate line and let it boost well beyond a safe level (30PSI)?

Now your trying to find out why you can't boost beyond 10PSI?

You probably created some boost leaks when you boosted to 30PSI. I would correct your mistake and properly tap the J-pipe and seriously inspect your turbo for damage. Then retrace the way you have your MBC vaccum lines and make sure they were properly hooked up and verify the wastegate functions properly.

 

[oldman]

1. What type of MBC (ball and spring OR bleeder)?

2. How exactly is it connected? (which fitting goes to where?)

3. Which direction are you adjusting the MBC? (CW or CCW for increasing boost?)

4. What do you mean by the way you tapped the j-pipe?

5. It is probably one of the dumbest thing one can do to let it boost to 30psi since all you needed to know with the test run was whether it will do over 10psi, let's hope the damages hasn't already been done.

 

[kenamond]

By disconnecting the vaccuum line from the WGA and running to 30psi, you just demonstrated that you don't know what you're doing. That doesn't tell you that the WGA is not sticking. It's telling you that without anything telling the WGA to open, it won't open. Not at all related. When it went past 20psi, you should've let off the gas, too.

I'm not sure how many threads you read about this, but I think you need to read a couple more.

I'm not sure from your description what you have on your compressor outlet for a nipple. But if you have a sealed nipple, it goes into the inlet of the MBC and the outlet of the MBC goes to the WGA. Loosen the Joe P MBC almost all the way and do a pull. It will never go below 9-10psi by the way. Then tighten the MBC some and do another pull. Eventually, your boost will settle above 10psi. Fine tune until you get to where you want to be.

And if you want to test your WGA in the future, run a vaccuum line straight from the compressor outlet nipple to the WGA with the MBC completely out of the loop. This should get you around 10psi boost.

 

[wishnfor4g63T]

Sorry guys when i said boosted to wonderfull 30 psi, I meant it could i stopped around 17 cause if it went over that it wasn't holding at all. Heh kinda felt bad for not letting you guys know! Anyhow, The reason for the Poor job on the J-pipe is because i had to work the next day and tapped it as quick as i could and hoped for the best. So now how do i make this 1/8th Barb?

I've used about 3 methods from people saying "Try This it will work!" So i'm like hell yea whatever makes it work. Method 1 = pressure line from the J pipe then to the wastegate. Method 2 = pressure line tee'd from the bov line to the wastegate. Method 3 = all the way at the top near the firewall the same line tap'd for my boost gauge. Simply because another guy had it that way and it worked.

In all the ways i've tried screwing both MBC's in or all the way out Never gives me more than 10-12 pounds.

To all DSM'ers who thought i damaged the turbo i also checked it for shaft play it's still fine. Thanks for the quick replies i'm going back out to play...well fix hopefully.

 

[kenamond]

Sorry guys when i said boosted to wonderfull 30 psi, I meant it could i stopped around 17 cause if it went over that it wasn't holding at all. Heh kinda felt bad for not letting you guys know! Anyhow, The reason for the Poor job on the J-pipe is because i had to work the next day and tapped it as quick as i could and hoped for the best. So now how do i make this 1/8th Barb?

I've used about 3 methods from people saying "Try This it will work!" So i'm like hell yea whatever makes it work. Method 1 = pressure line from the J pipe then to the wastegate. Method 2 = pressure line tee'd from the bov line to the wastegate. Method 3 = all the way at the top near the firewall the same line tap'd for my boost gauge. Simply because another guy had it that way and it worked.

In all the ways i've tried screwing both MBC's in or all the way out Never gives me more than 10-12 pounds.

To all DSM'ers who thought i damaged the turbo i also checked it for shaft play it's still fine. Thanks for the quick replies i'm going back out to play...well fix hopefully.

Method 1 is the "correct" way. If the nipple on the J-pipe is leaking, you have a boost leak that you need to fix. If you run a vaccuum line from the j-pipe to the WGA with no MBC, you should see around 10psi boost.

Do a search for more info on how to add a nipple to the j-pipe. There are numerous threads on this.

 

[oldman]

Also, how about answering my questions 1 and 2.

 

[wishnfor4g63T]

Okay "Oldman," Happy to have you help me on this problem. I've read more than a few hundred of your posts!

1. What type of MBC (ball and spring OR bleeder)? The Joe P look alike is a ball and spring. The other is the ebay one that is a bleeder. It worked flawlessly on my t-25.

2. How exactly is it connected? (which fitting goes to where?) ATM i have it tee'd off the bov line generally because around 4-5k i can get 13 pounds out of it till redline w/ no spikes.

"If you run a vaccuum line from the j-pipe to the WGA with no MBC, you should see around 10psi boost." Yes i get 10 pounds, i get 10 pounds just about any way i run it . Thanks guys for helping and fast too. I hope to one day be helping fellow dsm'ers!

 

[oldman]

2. How exactly is it connected? (which fitting goes to where?) ATM i have it tee'd off the bov line generally because around 4-5k i can get 13 pounds out of it till redline w/ no spikes.

1. Do not Tee the BOV line period. Make sure the fitting on your J-pipe is done properly and use that instead.

2. I want to know exactly which fitting on the respective MBC's are connected to pressure source vs. wastegate. The reason this is important is because the inlet/outlet fittings, as well the direction of adjustments, are completely opposite when comparing a ball/spring vs. bleeder type MBC's.

 

[wishnfor4g63T]

Okay, I'm back again. The way i have the MBC hooked up. Pressure source from j pipe which is the top line and the bottom goes to the wastegate. This is definitly a poor job on my part. i took one of the plastic t's that came from the air intake. Put that into the bend on the J pipe with some JB weld. I've heard people doing it and hell it stuck. As you can tell from my post's boost sucked. After 2 weeks of tinkering and getting help from friends i took the j pipe off again and cut the end sticking inside the J pipe like a stick. Took the car for a spin and this time i hit 11 psi.

....Well the farter i got in the rpms the more i boosted. My face said . Heh i made 2 hard passes with my car cause i was watching the gauge to see what i would hit (14 pounds) by 6k rpm and the needle spiked to 20 and i jumped off the gas. I popped the hood and the little T had came out of the j pipe but was still inside the rubber hose for the mbc. (sign of relief there)

Cough i know i'm going to get alot of "look at that dumb ass" remarks so fire away. Todays question is should i be using a bigger T? I'm going to use a metal one this time and get it welded in as soon as i can find a welder. OOORRR can i tap the turbo and put in a fitting just like the T-25 has? 10 psi is old i'm almost ready to take it to a shop and have them figure it out but i've got you guys so i'm good to go! Please help!!

BTW thanks Oldman for helping.

 

[DSMDirkah]

Ok I am sure this has been said already but, I would just tap the J-pipe and use a 1/8th NPT Barbed fitting (can be found at some hardware stores or Jegs). That is your boost reference line for your wastegate. Next hook your boost reference line to your MBC (depending if it is ball and spring type you need to hook it to the correct side). Then the other side of the MBC goes to your Wastegate. It's as simple as that! It is also a very good idea to place your boost reference as close to the turbo as possible to prevent over-spinning of the turbo due to boost leaks.

 

[Talesin]

First, run off a vac nipple welded on the j-pipe. You can drill and tap the fitting on the compressor housing outlet if you prefer.
Second, 10psi is the stock wastegate spring rate. You'll get 10psi with a straight vac line from the compressor outlet elbow to the wastegate boost reference nipple.

Which leads me to think that it may *be* just a straight line from the compressor outlet elbow to the WG at this point. Take the MBC apart and look inside... make sure that you have a ball and spring in there, and that the spring isn't broken. Happened to a couple people I know, just dropped to 10psi unexplainedly... and their spring had broken. You can replace it with the spring from a ball point click-pen, though you may need to trim it to length and bend the ends a bit to make it fit and work correctly.
Also, make sure you have it hooked up right way round. On a joe-p, the compressor outlet elbow line should go in the side opposite the screw, and the line to the wastegate should come out the side.

Otherwise, the adjustment screw may just be too far out... you can't drop below 10psi with an MBC (with an OEM WG actuator), no matter how low you set it.. might just have to take up the 'slack' in the adjustment screw.

 

[wishnfor4g63T]

Thanks Talesin, I've already done that =(. Last night i took the j pipe off put metal peice in there like a barb and put the j-pipe back on. Okay, i'm anxious, so i start the car after putting everything back together and walk to the engine bay. I left the line off the j-pipe just to see if there was enough air. A couple of rev's let me know it was spewing enough, put then line from the mbc back on the j-pipe and took it for a spin. It spooled up to 9 and then 10 and 11 and by around 7k rpm i was at 13 pounds.

Other than wasting gas on my 101 trips up and down the road i've gained 2 psi over my last set-up which leaves me very confused. I've used both MBC's and they both result in the same deal. No, i'm not running the line straight from the j-pipe to the wastegate.

1 last part i need to mention and i have no idea if this will play with the wastegate so read closely. When we first installed the 16g the middle ring i guess you could say was loose and oil flooded out the 02 houseing letting us know we 1. had a exhaust leak and 2. we didn't do something right. After a days break we got that tighted and crossed our fingers hoping it would work and everything has be flawless since then. Just about everytime i've taken the filter off and the j-pipe theirs a bit of oil left in it. not to bad, but you can tell it's been going thru it at a dripping pace. Would oil clog the wastegate so that it wouldn't work right? I tried blowing in the wastegate line just a few mins ago and it did absolutely nothing so thats when i wondered if that would have an effect?

Thanks guys for help! Y'm trying like hell to get this fixed!

 

[oldman]

1. If you're getting oil on either the cold or the hot side of the turbo, your turbo is shot. Is this a brand new turbo?

2. Pull the line going to the wastegate actuator and go for a test run, post back results.

 

[wishnfor4g63T]

I can already tell you the turbo isn't shot =p. I did take it for a run and it wound out the psi to 15 really quick. I backed off and limped it home. It has been boosting fine for weeks i've raced my friends stock wrx and passed it no problems at 10 pounds.

Btw the Turbo is new. It's a slowboys B16g, ported polished with bigger turbine. Like i said the oil leak isn't bad it's like a drip per 5 minutes i would say.

Thanks

 

[oldman]

I can already tell you the turbo isn't shot =p. I did take it for a run and it wound out the psi to 15 really quick. I backed off and limped it home. It has been boosting fine for weeks i've raced my friends stock wrx and passed it no problems at 10 pounds.

Btw the Turbo is new. It's a slowboys B16g, ported polished with bigger turbine. Like i said the oil leak isn't bad it's like a drip per 5 minutes i would say.

1. Regardless how much oil, you're not suppose to leak ANY oil out of the turbo, either the turbo is on its why out or you have excessive oil pressure/volume in the CHRA due to excessive oil feed and/or poor return. Have you check the turbo for shaft play? BTW what is a "SBR Big 16G"? I didn't know SBR makes turbos.

2. If you're able to boost to 15psi, the problem is either the MBC, line hook up and/or direction of adjustment. Use the ball and spring MBC and tell us which of the MBC fitting goes to the J-pipe and which goes to the wastegate, don't use terms like "top" or "bottom" because we have no idea how your MBC is mounted (orientation), use "the fitting inline but opposite to the adjustment knob" vs "the fitting perpendicular to the body of the MBC". Also tell us which direction (CW or CCW) you're turning the knob as well as how many turns have you turn the knob so far.

Some of your descriptions in this thread are confusing because you're assuming we're looking at exactly what you're looking at, which we're not. Either post pictures with your descriptions or pretend that you're talking to 5 year olds.

 

[wishnfor4g63T]

Ya know i would almost agree on the poor oil return. I had the 2g install kit, but didn't have any of the new lines. I'm thinking now would be a good time to go with ss lines huh. The turbo has i'd said paper thin shaft play. I've checked it everytime i've pulled the filter off because my t-25 had it very bad. It's always had this much play since the day i got it.

#2 okay i'm going to try to get pics later today. I know this has been frustraiting not only to me but probley to you guys also. My wife carries the digital camera in her purse and she's out atm with the kid. I do have a phone camera with the crappy view but it would work. I had been using the ebay bleeder type MBC because you just screw it in for less and screw it out for more pressure and thought; hell it's doing it's job why wouldn't it work? Figured i'd give the joe p clone a try and stuck it on with same results. Like i said the pictures are on the way. i'll give you guys what a look at what i'm dealing with and maybe someone will say eh retard do this . At least i'm hoping!

BTW Oldman the turbo is by MHI . I'm glad to see someone getting a laugh!!!

 

[kenamond]

The paper-thin shaft play is side/side or in/out? You should have no in/out shaft play.

Also, oil in the J-pipe may be coming from the VC breather, but there would be oil in the compressor inlet as well as the j-pipe. Do you have signs of oil in your compressor inlet?

I'm not familiar with the 16gs, but the oil return is a tube to the oil pan on the T25/T28/B28; it's not a "line". If you're somehow restricting the oil return flow, that could force oil past the seals.

 

[wishnfor4g63T]

Okay here are the pic's i promised. The ol phone camera isn't to shabby! I hope this shine's some light and if anyone needs a diffrent angle it will just take me a sec.

The red mbc is the ebay one i really trust. It worked with the t-25 with no spikes.

 

[oldman]

So which direction are you turning the ball and spring MBCto increase boost? Looks to me the adjustment rod is turned all the way out.

BTW, that ebay MBC sucks, I'm glade you're not using that one currently. Ball and spring (well built) is always better than a bleeder MBC, especial that ebay bleeder MBC.

 

[Talesin]

Wait... are you saying that yes you did put a barb into the compressor outlet elbow, or yes you did take the MBC apart and make sure you had an un-broken ball and spring inside? The top two of those three pictures definitely look like standard ball-and-spring, the third one I can't tell if it's a ball and spring or a bleeder type.

 

[oldman]

the third one I can't tell if it's a ball and spring or a bleeder type.

That is a TurboSmart ebay knock off bleeder MBC, one of the worst I've seen, do a search and you'll see.

 

[wishnfor4g63T]

The "turbosmart knockoff" actually works. It held up fine with my t-25. I can't really complain about it. The other (Joe P) has the 2 bearings in it with the spring. I blew in the bottem end while adjusting the knob and the more you spin it out the more air went thru. Blowing thru the top end locked the ball up and air just "bled."

Wait... are you saying that yes you did put a barb into the compressor outlet elbow, or yes you did take the MBC apart and make sure you had an un-broken ball and spring inside? Of what crappy job i did before; on a run i blew the peice of plastic inside the j-pipe out. That was my means of a nipple on the j-pipe for the boost source. Luckily the plastic stayed inside the tube that i was using and didn't go thru the fmic to the engine..... However this is a diffrent setup their is no plastic now. It is a metal peice connected with JB weld that holds up fine.

No matter how i turn the knob on the adjustment screw i still get the same amount of boost unless i adjust it where no air comes thru then the turbo is pretty much outta control. I've been toying with the car for 3-4 weeks now.

BTW about the oil thing yes it comes out of the inlet too but still not really bad at all just like a super small leak. My main concern was if it had something to do with gumming up the Wastegate.

Anyone see any problems with my methods or disagree how things are done here? I can take more pictures anytime. All the help is greatly appreciated!!

 

[oldman]

The "turbosmart knockoff" actually works. It held up fine with my t-25. I can't really complain about it.

Just because something works doesn't mean it works optimally nor does it mean it will work for a long period of time. Of all the threads I have helped troubleshooting, that MBC is one of the most problematic ones, do a search and you will see.

The other (Joe P) has the 2 bearings in it with the spring. I blew in the bottem end while adjusting the knob and the more you spin it out the more air went thru. Blowing thru the top end locked the ball up and air just "bled."

That is how a ball and spring is suppose to work. You still have not answered my question (asked 3 times already), which way are you adjusting the knob on the joe-p knock off to increase boost, IN OR OUT? How far have you turned the knob so far?

 

[2alpha]

I blew in the bottem end while adjusting the knob and the more you spin it out the more air went thru. Blowing thru the top end locked the ball up and air just "bled."

Isn't that essentially what you are looking for oldman? So that CCW right? based on normal screws and bolts? And if you are getting air from the turbo line to the MBC and the MBC is working then the Wastegate could be bad...or stuck. Also maybe the MBC that you are using isn't functioning correctly? Hopefully there is nothing in the air lines blocking airflow.