Turbo Oil Feed Diameter

[Rob Turbo 3]

I've been trying to find the parts I need to make an oil feed for my turbo project and the ideal solution would be to use the euroquip fittings from somewhere like rally design, that way I can get my brake hoses and oil feed bits at the same time!

 

I was planning on making an adaptor to screw into the block where the original oil feed went, to take it from an M16 to an M10, so I can use a banjo fitting at that end, then at the turbo end, I think it's M12 into the turbo, so was going to make another adaptor, at that end to accept a female M10 brake hose connector. The actual fittings and adaptors are not a problem, but, is the stinless brake hose A, large enough I.D. to supply oil to the turbo and B, up to the job of carrying hot oil?

 

Thanks,

Rob

[wracing 19]

When I did my turbo conversion, I found that the block threads aren’t metric! Some odd American thread went down to my local hyds place and he made me the hoses I needed. For a turbo feed and 2 * 1 metre oil cooler pipes it was £25! The pipe was rated up to 185degrees and 200bar!

 

That’s the way to go personally I think brake hose is to small with journal bearing turbots they need a high volume of oil!

[Rob Turbo 3]

Well my block is deffinitely M16 x 1.5, the last oil feed I had made at a hydraulics place cost about £60, I nearly needed picking up after they told me the price, should have asked before they made it but you live and learn, I certainly learned not to go back there for anything!!

[Henry Yorke 269 3 Cars]

Yes I struggled with mine as it was a special rare size and it also cost a lot.

 

You don't need a massive oil feed to the turbo as you run the risk of making an easy route for the oil to flow so you lose pressure in other parts of the engine where it is more critical. On a XU10J2TE, the oil is more of a lubricant as opposed to a coolant.

 

This is the feed on a TT engine

 

The key is to have a large return so pressure does not build up in the turbo or it will blow the seals (seen that happen before on a 2.0T)

 

Gerben Van De Lei of www.205turbo.nl fame and I had this discussion a few years back and he put a regulator in his for this reason so he could control the pressure.

 

Mine has a reducer in the pipe to restrict the flow as well (not got a pic to hand!!)

 

Hope this helps

[Ryan 99]

Double check before buying, but I seem to remember the T25 oil feed being an inverted flare 7/16UNF with a 24tpi pitch.

[EdCherry 34 1 Cars]

I've personally been taught not to use banjo fittings for oil systems as they restrict flow, could you not use swept or 90* bends?

Edited May 12, 2009 by EdCherry

[Rob Turbo 3]

Double check before buying, but I seem to remember the T25 oil feed being an inverted flare 7/16UNF with a 24tpi pitch.

 

 

Into the turbo itself? On mine there's an adaptor thing in it that's probably an unusual thread, but I've taken that out and it's a 12x1.5 thread that seals with a copper washer, so I was planning on making my own adaptor.

 

I've personally been taught not to use banjo fittings for oil systems as they restrict flow, could you not use swept or 90* bends?

 

I could go for a swept 90* bend, I was just going to use a banjo for ease of machining, scratch that then, I'll use the same fitting at both ends.

 

So if a restrictor is needed in the "regular" oil feed braided hose then the I.D. of the braided brake hose should be ok?

 

But will the braided brake hose be ok to use with oil?

 

Thanks,

Rob

[EdCherry 34 1 Cars]

Brake fluid is horrid stuff, so it should be able to cope with oil although dont take my word as gospel.

 

My notes from my dry sump lecturs have -8 (.5") bore as the smallest hose size hose used as a cam cover breather to the oil tank. Also noted - Avoid sharp 90* Bends, Use swept if possible. Do not use banjo type fittings. This is just going of the information I have, I couldn't comment on weather a brake line would be sufficent size (although I think not).

[Rob Turbo 3]

Just remembered, I have an old braided oil feed off a rover I think, I'm sure it's fairly thin, I'll cut it in half tomorrow and measure the I.D.

 

The I.D of goodridge #3 braided hose (3/8") is 3.5mm, which seems large enough? I'm sure I read something about ptfe not being well suited to oil, I suppose I could soak some ptfe tape in some oil and see what happens!

[welshpug 1,661]

I take it the standard XU10J2TE pipe is no use in some way even if adapted?

[Rob Turbo 3]

The standard pipe is steel with a small length of flexi pipe in it to allow a small ammount of movement, but I need the feed to go beside the head instead of behind it, which the standard pipe won't do!

[EdCherry 34 1 Cars]

Can you get an ID of that standard pipe as well while your at it as it will give you some indication of what size you need, also look at Tom F's tubby project as im sure it had some info on the oil feed pipe.

[Ryan 99]

From looking at a few site it seems like most oil feeds are -3 (3/16" - brake pipe size) or -4 (1/4"), so you should be fine with brake pipe.

 

I think you only need a restrictor with ball-bearing turbos.

[Rob Turbo 3]

Had a look through Tom's project thread and he used -4 fittings, which is 5.6mm I.D.

 

The I.D. of the original feed is around 5mm IIRC, that's the size of the hole through the adaptor on the turbo (12 x 1.5 to whatever the odd thread is on the other side!) Looks like I'm going to have to find a supplier of -4 fittings/hose!

[wracing 19]

i use the oil feed off the 2l turbo cut the end after the flexy pipe and joined onto it with a flex hyd hose (compression fitting) about 300mm long this then went to some uions, ill get some clear pic up tomorrow

 

 

look at this from garrett if your running the 2.0l turbo you dont need a restrictor

 

Does my turbo require an oil restrictor?

Oil requirements depend on the turbo's bearing system type. Garrett has two types of bearing systems; traditional journal bearing; and ball bearing.

 

The journal bearing system in a turbo functions very similarly to the rod or crank bearings in an engine. These bearings require enough oil pressure to keep the components separated by a hydrodynamic film. If the oil pressure is too low, the metal components will come in contact causing premature wear and ultimately failure. If the oil pressure is too high, leakage may occur from the turbocharger seals. With that as background, an oil restrictor is generally not needed for a journal-bearing turbocharger except for those applications with oil-pressure-induced seal leakage. Remember to address all other potential causes of leakage first (e.g., inadequate/improper oil drain out of the turbocharger, excessive crankcase pressure, turbocharger past its useful service life, etc.) and use a restrictor as a last resort. Garrett distributors can tell you the recommended range of acceptable oil pressures for your particular turbo. Restrictor size will always depend on how much oil pressure your engine is generating-there is no single restrictor size suited for all engines.

 

Ball-bearing turbochargers can benefit from the addition of an oil restrictor, as most engines deliver more pressure than a ball bearing turbo requires. The benefit is seen in improved boost response due to less windage of oil in the bearing. In addition, lower oil flow further reduces the risk of oil leakage compared to journal-bearing turbochargers. Oil pressure entering a ball-bearing turbocharger needs to be between 40 psi and 45 psi at the maximum engine operating speed. For many common passenger vehicle engines, this generally translates into a restrictor with a minimum of 0.040" diameter orifice upstream of the oil inlet on the turbocharger center section. Again, it is imperative that the restrictor be sized according to the oil pressure characteristics of the engine to which the turbo is attached. Always verify that the appropriate oil pressure is reaching the turbo.

 

The use of an oil restrictor can (but not always) help ensure that you have the proper oil flow/pressure entering the turbocharger, as well as extract the maximum performance.

[Powers 13]

Polytetrafluoroethylene (P.T.F.E) or Kevlar (Dupont Trade mark) is perfectly suited for the transfer of oil.

P.T.F.E is an engineered plastic resin in the fluorocarbon group. This resin displays outstanding chemical resistance to a wide variety of chemicals. The only know classes of chemicals that attack Teflon are molten alkali metals such as Sodium and Potassium and halogenated chemicals like Fluorine Gas or Chlorine Trifluoride. Other halogens such as Freon are known to effuse at a given rate.

 

Almost no substance can stick to Teflon. This property ensures the purity of any product transferred via a Teflon Hose. It also allows for alternate use with different products.

 

Teflon (PTFE) hose is flexible and strong and when combined with stainless steel braid can perform under high pressure and continuous flexing and vibration conditions.

With a wide range of chemicals compatibility Teflon Hose can handle an almost endless variety of fluids at extremes of pressure and temperature.

Teflon hose can withstand temperatures from -100°F to +500°F (-73°C to + 260°C) under most operating conditions.

 

Applications

High Pressure & High Temperature for Brake, Clutch and Power Steering Lines, Engine/Transmission lubricants, Clutch fluid, Nitrous Oxide, Power Steering, Hydraulic

and Air Conditioning.

Edited May 13, 2009 by Powers

[Rob Turbo 3]

Thanks for the info, I still haven't measured the I.D. of the standard oil feed pipes (rover and peugeot) but thanks to the above information I know I can use the brake hose, if 3mm I.D. is too small I can go for #4 goodridge hose which is 5mm I.D. although I'd have to go for different fittings at both ends, which isn't really a problem as I haven't made any adaptors yet!