Garrett GT28 Banjo Bolt Oil Restrictor Size

Hey Guys

The banjo bolt that came with my GT28/25 braided oil feed line has a 1.5mm restrictor size hole while the banjo bolts oil restrictor from GCG has huge 4mm hole and GCG assures me this size is correct.


Most posts I’ve come across recommend 1.5mm size for Garrett turbo’s

What size are you guys running with your GT28s?

Thanks

Luke

i was running the fittings i got with my oil lines 4mm restrictor and turbo started to leak through the oil seal but not out the exhaust but between the 2 housings..........had it rebuilt under warranty and explained to me, that due to the high oil pressure in honda engines, it makes it too high for the turbo charges, i was advised to run a 40thou (i been told that is 1mm) restrictor, but im gonna try using a 1.5-1.6mm restrictor to start with.

good luck....

Quote:

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Originally Posted by IEVAQ8

i was running the fittings i got with my oil lines 4mm restrictor and turbo started to leak through the oil seal but not out the exhaust but between the 2 housings..........had it rebuilt under warranty and explained to me, that due to the high oil pressure in honda engines, it makes it too high for the turbo charges, i was advised to run a 40thou (i been told that is 1mm) restrictor, but im gonna try using a 1.5-1.6mm restrictor to start with.

good luck....

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I turned my car on for first time with the 4mm and oil made it into the compressor housing on idle n didn't drive anywhere..

I don't think that happened with the 1.6mm

So my turbos fuked now?

ur turbo cant be fuked from too much oil, mine had too much oil pressure for over 4 months before the seal satarted to leak, but when they stripped the turbo, the seal wasnt even broken or cracked, just the oil had been pushed past it.......

i reckomend u use the 1.6mm restrictor

Quote:

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Originally Posted by IEVAQ8

ur turbo cant be fuked from too much oil, mine had too much oil pressure for over 4 months before the seal satarted to leak, but when they stripped the turbo, the seal wasnt even broken or cracked, just the oil had been pushed past it.......

i reckomend u use the 1.6mm restrictor

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Yeah cool

Even on the Garrett website they state oil pressure as one of the course of oil leak into the compressor housing but not say the turbo needs rebuilding.

Just a list of what to check and change..

I'm thinking the return lines to small

Looks big on the out side but only about 7-8mm across

u got a pic of the 1.6mm restrictor??? and what brand or where it came from???

cheers

Quote:

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Originally Posted by IEVAQ8

u got a pic of the 1.6mm restrictor??? and what brand or where it came from???

cheers

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Still to much oil IMO

I'm going to look for a 1mm

I tested this by running the oil return line to an oil pan...

Holy crap the 1.6mm pushes lots of oil through and thats just on idle


What size oil return line are you running?

Any change I've put the flange to low?http://www.scruffie.com/luke/car/b16...an_drilled.jpg

As long as it is above the level of the oil it should be fine


Also, Im using a 1.5mm restrictor on my journal bearing turbo and AFAIK ball bearing turbos require less oil so you would probably need 1mm restrictor

Quote:

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Originally Posted by ZeForce

As long as it is above the level of the oil it should be fine


Also, Im using a 1.5mm restrictor on my journal bearing turbo and AFAIK ball bearing turbos require less oil so you would probably need 1mm restrictor

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its at the same level as the oil and when the cars off and I removed the oil line connector oil drips out slowly but once the car start the oil level would change right? While oil moves round the motor.

Yeah man 1.6 is way to big that’s for sure after my little test.

Dam banjo bolt is still leaking after all that fuking round as well...

Plus I'm quite sure the turbo seals are gone event though it brand new!!

If I push air throw the compressor inlet and cover the compressor outlet I can hear air going into the oil part of the turbo.

whats the oil restricter ?

Quote:

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Originally Posted by datzlr

whats the oil restricter ?

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It restricts the amount of oil going to the turbo ball bearing

hey man mine is a 8mm-10mm return line yours looks big enough and its at the top of the sump so thats right, your turbo should be fine but you will need to put the smaller restrictor in it for sure i have a GT28R here with the right size oil restrictor i can put a pic up of and meassure for you? and make sure you have both copper rings on the bolt when you put it back in because that will make it leak as well

Quote:

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Originally Posted by lookingforboost

hey man mine is a 8mm-10mm return line yours looks big enough and its at the top of the sump so thats right, your turbo should be fine but you will need to put the smaller restrictor in it for sure i have a GT28R here with the right size oil restrictor i can put a pic up of and meassure for you? and make sure you have both copper rings on the bolt when you put it back in because that will make it leak as well

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Yeah Ryan I'm quite sure that's the problem.

I called GCG for a price on a rebuild and they asked what was wrong and I explained what's happening.

They told me my turbos fine as the seals are not air tight like I thought they would be and I just need the right restrictor to match my motors pressure.

My dad and I are going to weld and redrill the restrictor with a 1mm hole tonight :thumbsup:

> They told me my turbos fine as the seals are not air tight like I thought they would be

AFAIK, generically, there are two types of turbo seals.

Carbon and dynamic.

The new GT series should be dynamic which depend on the the spindle rotating to function.

Carbon seals, were used on non-water cooled turbos and turbos which were installed low, ie below the oil level in the sump and maybe on draw through installations.

This is about the limit of my turbo seal knowledge, so feel free to jump in.

I believe carbon seals are available for T3 frame turbos, if you're rebuilding the GT, it might be something to look into.

There's a book by Graeme Smith for Graeme Bell (I think, Wollongong uni has a copy) detailing oil routing which you might be of interest.

Nick.

Quote:

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Originally Posted by nd55

> They told me my turbos fine as the seals are not air tight like I thought they would be

AFAIK, generically, there are two types of turbo seals.

Carbon and dynamic.

The new GT series should be dynamic which depend on the the spindle rotating to function.

Carbon seals, were used on non-water cooled turbos and turbos which were installed low, ie below the oil level in the sump and maybe on draw through installations.

This is about the limit of my turbo seal knowledge, so feel free to jump in.

I believe carbon seals are available for T3 frame turbos, if you're rebuilding the GT, it might be something to look into.

There's a book by Graeme Smith for Graeme Bell (I think, Wollongong uni has a copy) detailing oil routing which you might be of interest.

Nick.

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Hey Nick

So the faster the turbo spins the better the seal works yeah?

How my D16Y1 box going?

Lukenzen i was running 1.5mm on my old gt28r and that was fine but i had the same issue with an older gt28 running 4mm where it didnt break the compressor seal but it would leek through and i poored out over 1 litre of oil from my intercooler.

Also i put my oil dump here...similar pos to yours and its fine.

http://i101.photobucket.com/albums/m...c/IMGP3112.jpg

Quote:

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Originally Posted by FastFwd

Lukenzen i was running 1.5mm on my old gt28r and that was fine but i had the same issue with an older gt28 running 4mm where it didnt break the compressor seal but it would leek through and i poored out over 1 litre of oil from my intercooler.

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Thanks FastFwd

I think 1mm should fix the problem.

I was amazed just how much oil the 1.6mm pushed out, was close to a liter in abut 30 seconds..

Great news about the sump, I didn't wanta have to drill that crap again lol

I originally drilled it and then using a copper fitting i screwed it into the sump and used a nut on the other side to lock it tight and i sealed it with some plumbing tape...that was great for about a year but in my last build i removed my sump and got someone to weld that copper fitting onto the sump. Havent had one issue since.

Quote:

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Originally Posted by Lukezen27

Thanks FastFwd

I think 1mm should fix the problem.

I was amazed just how much oil the 1.6mm pushed out, was close to a liter in abut 30 seconds..

Great news about the sump, I didn't wanta have to drill that crap again lol

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yeah that sounds about right... when I first ran my car without a restrictor I was blowing smoke out of my exhaust badly and my oil feed was flowing over 1 litre in 15secs lol now Im using 1.5mm restrictor and it flows ~500mL in 15 secs which is the correct amount needed for a journal bearing turbo. Like I said before a BB turbo requires less, maybe 250-300mL in 15 secs

> How my D16Y1 box going?

Been busy moving.

What family have loving to as 'JUNK, get rid of it'.

Don't know why they hate Honda's some much. he, he. :D

Nick.

Quote:

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Originally Posted by nd55

> How my D16Y1 box going?

Been busy moving.

What family have loving to as 'JUNK, get rid of it'.

Don't know why they hate Honda's some much. he, he. :D

Nick.

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So what about >So the faster the turbo spins the better the seal works yeah?>

familys love to throw the good shit away :(

Try this-
http://www.atpturbo.com/Merchant2/merchant.mvc
3rd row of items down. They have more somewhere on the site.

I made my own restrictor by drilling a 1.5mm hole in a grub screw and then tapped a thread inside the 1/4" fitting at the end of my oil feed line, worked well :thumbsup:

The if your banjo bolt is attached directly to the feed then its hard but mine can seperate and you can put a restrictor in between the feed screw and the banjo and it cost me around $2 from hosemart or you can get it from enzed also but i dunno what its like in other states.

I'm going to buy a bigger oil return line this weekend just to be safe.

While the hole I dripped and the flanged can handle bigger the hose I've got is only about 6mm across internally.

i got some sard High temp hose. The internal diameter would be around 10mm. I think 6mm should do you fine anyways lukenzen. Its only and remember the oil delivery line is 1.5mm so 6mm for the dump is more than enough.

Quote:

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Originally Posted by FastFwd

i got some sard High temp hose. The internal diameter would be around 10mm. I think 6mm should do you fine anyways lukenzen. Its only and remember the oil delivery line is 1.5mm so 6mm for the dump is more than enough.

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Might wait and see how the 1mm coze with the 1.6mm the return oil was squirting it out and that was with the hose in a straight line not connected to the sump.

Might buy some cheap oil and do that test again with the 1mm

hmm, this is slightly concerning. I just bought my oil feed line from Michael @ GCG and I had questions regarding oil pressures and restrictor, I asked him and he said that I would not need one...

I'm hearing from you guys that you do. Guess I'll need to revisit this issue again!

Quote:

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Originally Posted by B16

hmm, this is slightly concerning. I just bought my oil feed line from Michael @ GCG and I had questions regarding oil pressures and restrictor, I asked him and he said that I would not need one...

I'm hearing from you guys that you do. Guess I'll need to revisit this issue again!

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100% you need one for Honda's

GCG don't know shit when it comes to Honda

lol try motosport connections, that's where most custom work goes

Hosemart in WA is awesome. They pretty much have every type of host or fitting you can buy. and the guys there have knowledge of which turbos need which etc even though they dont specialize in automotive they seam to know alot. Plus they are very quick workers and i like that.

Quote:

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Originally Posted by Limbo

lol try motosport connections, that's where most custom work goes

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I'm off to motosport On Sat..

Dam GCG bold exploded when my dad tried to weld it :p

Luke, if your running a GT28 and are picking up a restrictor on Sat, would you mind getting me one too and I'll fix you up?
I'm driving down to Nowra then to help out a fellow crx'er otherwise I'd go myself.. if not no worries, I'll fix it up when I can :)

Quote:

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Originally Posted by B16

Luke, if your running a GT28 and are picking up a restrictor on Sat, would you mind getting me one too and I'll fix you up?
I'm driving down to Nowra then to help out a fellow crx'er otherwise I'd go myself.. if not no worries, I'll fix it up when I can :)

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Yeah I'll help you out but what type are you gong to run straght connect or banjo bolt

Guys

Anyone see any problems tested the oil feel line bolt withput actually bolting up the manifold?

I have everything still connected but the turbo and manifold cable tied to where the a/c radiator should go..

it wont hurt anything, but i wouldent run it for too long, it will sound terrible and probably wont run smoothly but should be fine just to test the oil flow for a minute or so.

Quote:

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Originally Posted by Lukezen27

Guys

Anyone see any problems tested the oil feel line bolt withput actually bolting up the manifold?

I have everything still connected but the turbo and manifold cable tied to where the a/c radiator should go..

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Yeh should be fine to run. Its very loud and rough though.

To save any confusion, for best results when using a Garrett GT turbo,
Use a 0.6mm restrictor in the oil feed line.
Be mindful the following should also apply,
The oil drain must be of adequate size & free flowing without kinks or dips.
Try to drain back to sump above the oil level.
The B16A~B16B~B18C lend themselves well to this with an available boss on the block that can be drilled & tapped to accommodate an AN fitting.
(To the left of the dip stick – lower portion of block)
Also, don't mount the turbo more than 15deg off horizontal - shaft orientation.

If the GT is leaking from the rear, fit the restrictor & it should fix itself…
The rear seal is carbon.
If it’s from the front, Bad luck

Hope that helps

Quote:

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Originally Posted by TODA AU

To save any confusion, for best results when using a Garrett GT turbo,
Use a 0.6mm restrictor in the oil feed line.
Be mindful the following should also apply,
The oil drain must be of adequate size & free flowing without kinks or dips.
Try to drain back to sump above the oil level.
The B16A~B16B~B18C lend themselves well to this with an available boss on the block that can be drilled & tapped to accommodate an AN fitting.
(To the left of the dip stick – lower portion of block)
Also, don't mount the turbo more than 15deg off horizontal - shaft orientation.

If the GT is leaking from the rear, fit the restrictor & it should fix itself…
The rear seal is carbon.
If it’s from the front, Bad luck

Hope that helps

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nice info adrian............
mine was leaking from rear, but as it was under warranty i made roto master in victoria rebuild it and change all the seals for free................ i have gone with the recommended 40thou (1mm) restrictor............so far so good (just got it going today)

Quote:

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Originally Posted by TODA AU

To save any confusion, for best results when using a Garrett GT turbo,
Use a 0.6mm restrictor in the oil feed line.
Be mindful the following should also apply,
The oil drain must be of adequate size & free flowing without kinks or dips.
Try to drain back to sump above the oil level.
The B16A~B16B~B18C lend themselves well to this with an available boss on the block that can be drilled & tapped to accommodate an AN fitting.
(To the left of the dip stick – lower portion of block)
Also, don't mount the turbo more than 15deg off horizontal - shaft orientation.

If the GT is leaking from the rear, fit the restrictor & it should fix itself…
The rear seal is carbon.
If it’s from the front, Bad luck

Hope that helps

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Thanks Adrian :thumbsup:

The smallest I could find was 1mm and I've installed that, no more smoking out the tail pipie :)

Where can we get the 0.6m restrictor?

Mine was leaking both front and back :(

pretty sure i have one here i'll have a look . most of the garrett turbos have them in already my T28 did so i didnt have to change it at all!

i ran this with my gt28r and no issues at all

Quote:

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Originally Posted by IEVAQ8

nice info adrian............
mine was leaking from rear, but as it was under warranty i made roto master in victoria rebuild it and change all the seals for free................ i have gone with the recommended 40thou (1mm) restrictor............so far so good (just got it going today)

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Quote:

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Originally Posted by Limbo

i ran this with my gt28r and no issues at all

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Possibly the turbo has problems :o

Quote:

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Originally Posted by Lukezen27

Possibly the turbo has problems :o

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i hope not, should be just a wear in problem.
make urself that .6mm one!

Quote:

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Originally Posted by Limbo

i hope not, should be just a wear in problem.
make urself that .6mm one!

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Yeah maybe

I'm going to check the piping shortly...

I've e-mailed Performance Wholesalers

HKS Oil Restrictor 0.6mm PN:4499-RA061

Hey Luke, the chap we saw said he had a smaller one (smaller than 1mm) so if you still need it you could go down. I'm pretty sure he said it was .6mm.

im using a restrictor from GCG. turbo is a garrett gt25r. Perfect operation.
oil feed fittings are -4AN and the restrictor is just an insert into a regular speedflow AN fitting.
http://gcg.com.au/turbo/ViewProduct.aspx?ProductID=140

if you use a restrictor and its still blowing oil past the seal then its time for new turbo. lol

Quote:

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Originally Posted by iced

im using a restrictor from GCG. turbo is a garrett gt25r. Perfect operation.
oil feed fittings are -4AN and the restrictor is just an insert into a regular speedflow AN fitting.
http://gcg.com.au/turbo/ViewProduct.aspx?ProductID=140

if you use a restrictor and its still blowing oil past the seal then its time for new turbo. lol

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Na the 1mm fixed the problem :)