Turbo Oil Supply

[Talasas]

Hey guys,

I've been looking around at what people have said about supplying oil for a turbo on a 4AGTE. Naturally the first idea I had was to fit a tee to the supply for the oil cooler and use that but then according to WC Engineering:

No matter what turbo you choose, it will need an oil supply. This needs to be a pressurized oil supply, so don't think that you can tap into the oil cooler lines.

and then it explains how tapping into the oil pressure sender line is a better idea. Then finally it goes on to contradict itself:

The feed to the turbo will need a restrictor in the line to reduce the flow of oil. The turbo only needs a small steady flow, not the full pressure.

So why can't I use the feed coming from the oil cooler sanwich plate on the block? It has a pressure regulator was my only concern.

[thechuckster]

some oil-cooler sandwich plates (and i'm not sure what the 4AGE looks like) have a thermostat in them so they ony allow oil to pass thruu when the oil is hot. If you replaced the factory plate with a simple adaptor and remoted a cooler with a bypass thermostat, then it would be a good place.


edit: the restricter they're talking about is the banjo-connector at the oil inlet on the turbo. The hole from the pipe to connector on my turbo (t25) is quite small compared to the ID of the hose.

note: old-style sleeve bush turbo bearings don't need a restrictor, anything with a ball--bearing core does.

[Talasas]

From what I know the 4AGE only has a relief valve on the sandwich plate and that is all.

I have to find out what sort of bolts they are, I just bought some BSP fitting and they aren't BSP.

[roadsailing]

it doesnt contradict itself, but isn;t worded fantastically.

it needs a pressurised supply, and it does need to be restricted a bit, as you dont want the full flow of oil through the turbo bearing.

i think the oil cooler lines is under very little pressure, and it isnt a constant feed.

on my 4AC there was a pressure relief falve on the oil pump, i;d assume the 4AGE is the same.

just T into the oil pressure sender fitting and get the feed from there, like everyone else does. dont mount the T joiner to the block or the turbo, or it will break from vibration. make sure there are no kinks in the hoses too.

drain back to the sump, weld in a barb fitting for it.

[Sunchaser]

From what I know the 4AGE only has a relief valve on the sandwich plate and that is all.

I have to find out what sort of bolts they are, I just bought some BSP fitting and they aren't BSP.

I'm not exactly sure what the Toyotas use, but my Scorpion (with Sigma turbo) sandwich plate uses NPT. At 1st glance NPT and BSP look the same but there were a few slight differences. Basically when i tried screwing a male BSP fitting into the female NPT thread it only went in about 2mm. The proper NPT fitting went in at least 10mm.

[wilbo666]

In the book "Maximum Boost" by Corky Bell, he says something along the following.

The following is a good guide for oil pressure for almost all turbos
Idle 5psi (hot)
Readline 25pis (hot)

I'll double check the figures at some stage.

He talks about using a restrictor to acheive this.

Cheers
Wilbo

[30psi 4agte]

dont mount the T joiner to the block or the turbo, or it will break from vibration.
.

Listen to this !!!! I have had it happen to me and had to pull the engine down as i had to drill out the excess brass

This what i have done to stop the cracking issue now. Notice that the sender bolted to the block to stop the fitting from cracking now!

Oil flow to a turbo can be critical to its survival !. Different types of turbos require different amounts of oil flow to survive.

For example a bush bearing turbo requires approx 2.5l per min and a BB turbo doesnt need as much requiring 1-1.5 L per min.

The way to check your oil flow capability is to pull off the line before the turbo and place the line into a measuring flask of some sort. Then start the car and run for 15 sec. Measure the amount of oil pumped out and times it by 4 to get the amount per min.

I dont think that the amount of pressure is of any concern as long as there is pressure. Basicly the oilpressure that the engine uses is fine.

P.S you will want to check the amount a bush bearing turbo requires by ringing any decent turbo place and asking.they will beable to give you the exact amount required. It was about 4 years ago that i checked this on my old turbo so i cant be sure the 2.5 L in correct.......... Although i think it is !!!

[Talasas]

The reason I didn't want to tap into the oil pressure sneder was that it's mounted under the power steering bracket and I'm not too sure there's enough room to even run a hose out to a tee. I will have to check it out, these fittings are a downright bastard to find.

This is what I currently have in mind, mainly because I'm an idiot and thought that the oil cooler return already in the sump would be enough so I didn't drill the sump while I had it off! Arrgh.

[Talasas]

Oh and 30psi, where'd you get the fittings from?

[30psi 4agte]

The speed flow ones in the pic ??

you can get them from O.G speed shop. They arent cheap though.

you can go here to get an idea of the parts you will need. Then write down all your part no.
Ring O.G and get a price.

http://www.speedflow.com.au/

It can be done alot cheaper if you dont want the fancy fittings using brass fittings.

[roadsailing]

i know your schematic isnt representative of the actual setup, but make sure the turbo oil drain is as near to vertical as possible, and goes straight into the sump (well, as straight as it can)

i'd highly reccomend buying maximum boost too, covers all of the basics very well, i'm helping a mate with a turbo 4AGE and am constantly remembering things from the book.

good luck with it!

[Talasas]

Thanks guys. I'll start my search tomorrow morning, at this stage I'll buy what I can get but brass fittings would be fine.

[feral4mr2]

i recomend taking the oil pressure doobie from the block, running a braided line from where the pressure doobie was to a remote mounted tee peice that holds the oil pressure doobie and the braided line/feed to the turbo. and use steel fitting's, not brass.

what i did on the feral anyways after nearly losing the engine from a tee peice mounted to the block with the oil pressure doobie cracking from engine vibrations and weight of the oil pressure doobie. (pics to follow if i can find them).

[30psi 4agte]

i recomend taking the oil pressure doobie from the block, running a braided line from where the pressure doobie was to a remote mounted tee peice that holds the oil pressure doobie and the braided line/feed to the turbo. and use steel fitting's, not brass.

what i did on the feral anyways after nearly losing the engine from a tee peice mounted to the block with the oil pressure doobie cracking from engine vibrations and weight of the oil pressure doobie. (pics to follow if i can find them).

Sounds like someone has a slight drug addiction !

[thechuckster]

nah ... it just explains why feral's so short...