Why is my 14B both oil and water cooled

[DeadsEvolution1]

So I am still kinda new to these cars but I wanted to know why our cars turbo's are both oil and water cooled? I heard it was for reliability or something is that true? I'm also wondering if I can remove the water cooled lines and just have it oil cooled only? Maybe a crazy question but just curious

 

[Rogan]

The oil section is much more for lubrication, and the water is to aid in cooling the center-section. You 'can' remove the watercooling portion, but why?

Straight from Garrett:

Oil & Water Plumbing

The intake and exhaust plumbing often receives the focus leaving the oil and water plumbing neglected.

Garrett ball bearing turbochargers require less oil than journal bearing turbos. Therefore an oil inlet restrictor is recommended if you have oil pressure over about 60 psig. The oil outlet should be plumbed to the oil pan above the oil level (for wet sump systems). Since the oil drain is gravity fed, it is important that the oil outlet points downward, and that the drain tube does not become horizontal or go "uphill" at any point.

Following a hot shutdown of a turbocharger, heat soak begins. This means that the heat in the head, exhaust manifold, and turbine housing finds it way to the turbo's center housing, raising its temperature. These extreme temperatures in the center housing can result in oil coking.

To minimize the effects of heat soak-back, water-cooled center housings were introduced. These use coolant from the engine to act as a heat sink after engine shutdown, preventing the oil from coking. The water lines utilize a thermal siphon effect to reduce the peak heat soak-back temperature after key-off. The layout of the pipes should minimize peaks and troughs with the (cool) water inlet on the low side. To help this along, it is advantageous to tilt the turbocharger about 25° about the axis of shaft rotation.

Many Garrett turbos are water-cooled for enhanced durability.

 

[gofer]

there is discussion of this scattered through out the forums here... i personally don't run coolant through my 16g but I DO have a turbo timer to give the thing a chance to cool down after driving it. they aren't necessary but mitsubishi designed them like that for a reason i guess? if you don't run coolant through it at least get a TT.

 

[DSM1G90]

don't run coolant through my 16g

Why add the risk?

Mitsu designed that for a good reason since they didn't install TTs as a stock requirement, but did put the warning in their manuals and even on the warning sticker that is on the sun visors to let the car idle for a bit after a good turbo run and not shut the motor off immediately afterwards that same turbo run as well.

With the combination of oil and water going through our turbos, its amazing how both can extract the heat away very well.

-DSM

 

[gofer]

did you only read those 6 words in my post? as i stated earlier i personally don't run coolant through my 16g but I use a turbo timer that allows the car to idle to prevent the oil from coking in the turbo.

i would like to run waterlines but my BEP hotside doesn't allow it... im not recommending anyone to remove their waterlines and install a TT. im just throwing out my experience with my car and have had no problems running my 16g with no waterlines.

 

[Gravity Fed]

roughly translated: Your not a mechanical engineer. The people who designed the turbocharger are.

While you can argue that it will reduce heat added into the cooling system, your going to find that the heat will redirect itself into your oiling system. Which is not where you want to see an increase in temperatures.

 

[DeadsEvolution1]

I figured it was for extra cooling and I do not have a turbo timer but I do let the car sit on idle for about a minute before I get out and I have the fans wired so I can turn them on by a switch even if the car is in the off position. I just wondered if It was possible to remove it or not.

I just wondered if that would keep my coolant temperatures down or not. I am running a 90 oil cooler instead of the stock one that has coolant running through it.

After all this I will still run the lines I was just wondering if I could remove them and what the cost of that would be to my turbo. I leave my fans on for about 10 minutes after I get out of the car (that's if I am home) if not I just sit there for a minute texting away.

 

[Yngvar]

why leave your fans on its not going to help cool the engine down only your radiator

 

[JusMX141]

So I am still kinda new to these cars but I wanted to know why our cars turbo's are both oil and water cooled? I heard it was for reliability or something is that true? I'm also wondering if I can remove the water cooled lines and just have it oil cooled only? Maybe a crazy question but just curious

You'll find oil and water cooled turbos on cars that were turbocharged from the factory. The manufacturer assumes that 99% of the asses in the seat of that car will not allow it to cool down properly, so the coolant is in place to reduce the amount of oil coking in the event that the car is shut down hot after being beat to hell.

If you're planning on running a 14B without water, it's probably a good idea to source the oil supply to the filter housing in order to provide a more consistent flow of oil, although you'll need to use an inline restrictor to prevent over-oiling the turbo as the filter housing can provide over 100psi of oil pressure in some cases.

As long as you allow the car to idle a bit before shutdown you'll be OK with no water. If your house is buried in city streets or down a long driveway that would require a good cruise at a low engine speed, you won't have to change your driving style at all.

 

[Rogan]

why leave your fans on its not going to help cool the engine down only your radiator

Exactly what I was thinking.. Especially with no true water circulation taking place, this is a pointless practice.

 

[DeadsEvolution1]

I leave it on because the fan still blows air around the bay of the engine, but I guess you're all right it doesn't do anything but oh well. I Probably wont' remove the coolant lines until a later stage or not even at all. I am going to be putting on and EVO III Big 16g in the next couple days I just wanted some opinion about it

 

[DSM1G90]

the fan still blows air around the bay of the engine

..like major hot air that is being sucked in by the fans .. I don't see any cooling going on here-just keeping things hot under the hood like being in a big convection oven with those fans running and pulling in the hot air from the radiator.

Just let the thing cool down the way it came out of the factory. It aint gonna hurt none..

am going to be putting on an EVO III Big 16g

This is what's on my vehicle and I have both coolant and oil lines attached. These units love this dbl cooling - keeps them running longer.

-DSM

 

[DeadsEvolution1]

Anyone tell me how to take the Transmission seal out? The one that seals when the axle is in? I sat there with a flat head screw driver for about 10 minutes and couldn't get it to come loose

 

[Black94DSM]

I have not taken apart a 14b but a buddy of mine told me that the stock bushings in them are tiny. For that reason alone I would try to stay away from just oil cooling the turbo. If you can put coolant to it too.

 

[JusMX141]

I'm not sure what that's supposed to mean....a 14B's journal bearings are .005" smaller (the thickness of a sheet of notebook paper) on the outside diameter than a Garrett T3's journal bearings, and most Garrett T3/T4 turbos do not have the provision for water.

It may have something to do with the oil plumbing- most MHI turbos are designed to be supplied from the head while Garretts require more oil flow to keep the journal bearings floating....this is evident by the size of the oil supply hole at the bottom of MHI and Garrett turbos. However, as stated above, I don't feel it's wise to deprive a MHI turbo of coolant and continue to feed from the head; move the oil supply to the filter housing and use a restrictor to be sure you do not over-oil the turbo.

 

[Black94DSM]

I was waiting for you to come back to this thread. As I said I heard it from a friend. I know you rebuild turbos so its good that you said that.

Maybe I will feed my 14b with oil only. Hmmm. Of course If I were to do it, it would be from the OFH only. How big of a restrictor should I use?

Thanks for clearing that up for me.

 

[JusMX141]

.0625" to .078" should do nicely...the larger restrictor would be a better choice for a stock block with the balance shafts still in place, or a shaftless block with a modified pressure relief valve to lower the engine's operating oil pressure.


If there's a way to incorporate the banjo fitting at the turbo end of your stock 1G oil supply line into your filter-housing feed line, do it....there's a restrictor built into the banjo fitting at the turbo end of the 1G's stock oil supply line.

I think Mitsu's intent from the factory was to keep the amount of oil supplied to the turbo at a minimum and supply the cartridge with coolant to minimize the effects of oil coking as there is less oil present with a head feed (similar to how a ball bearing turbos operates on very little oil but requires coolant). They've built a stout journal-bearing center housing that operates well on very little oil unless it's pushed to the limit....however, if you take the coolant out of the equation, the head alone will not provide enough volume of oil to allow proper cooling.

 

[Defiant]

http://www.dsmtuners.com/forums/han...thout-water-merged-9-8-coolant-lines-oil.html

 

[Black94DSM]

.0625" to .078" should do nicely...the larger restrictor would be a better choice for a stock block with the balance shafts still in place, or a shaftless block with a modified pressure relief valve to lower the engine's operating oil pressure.


If there's a way to incorporate the banjo fitting at the turbo end of your stock 1G oil supply line into your filter-housing feed line, do it....there's a restrictor built into the banjo fitting at the turbo end of the 1G's stock oil supply line.

I think Mitsu's intent from the factory was to keep the amount of oil supplied to the turbo at a minimum and supply the cartridge with coolant to minimize the effects of oil coking as there is less oil present with a head feed (similar to how a ball bearing turbos operates on very little oil but requires coolant). They've built a stout journal-bearing center housing that operates well on very little oil unless it's pushed to the limit....however, if you take the coolant out of the equation, the head alone will not provide enough volume of oil to allow proper cooling.

So the stock line has a restrictor on it, what size is that? I have a 94 water pipe that has the water return welded shut, but it does still have the nipple to go to the stock oil water cooler. Could I just use that nipple to return the water with?

Trying to get away from buying another water pipe. I'm not going to be on the 14b for long(hopefully).

 

[gofer]

^^ your probably better off starting a new thread...

 

[IceMinion]

I have seen a couple people run their turbos without water cooling, they didn't last very long, started smoking wore out...

Not saying that it WILL happen, but in my opinion, its silly to run without the added safety of having water lines....our mitsu's have enough going against them