I'm currently assembling a Mazda rotary 12A based vehicle in the interest of adding FI. These engines don't have an easy place for the turbo drain oil to return to. I'm planning on oiling the turbo with a small, separate standalone lubrication system. I have a small fluid reservoir, a suitable electric pump and a small oil cooler so should be good to go. My question is: Now that I don't HAVE to use standard motor oil for the turbo, would use of any other lubricant be advantageous for this purpose? I'm thinking something with lower viscosity so as to help reduce lag and spool time. I've seen those gentleman who make the hobby jet engines out of old turbos use ATF in apparently successful attempts to reduce the shaft friction. Mods: might I want to move this to the Automotive Lubricant Engineering area? Apologies if that's more appropriate.
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Standalone turbocharger lubrication
- Thread starter pmrobert
- Start date
Lou Scannon
Automotive
You might find more informed advice in the Lubrication Engineering Forum. My only advice is determine what actual viscosity a turbo being lubricated with engine oil is getting at operating temperature, and use that as a guideline. Now if you want to go lower viscosity than that, you can follow in others' footsteps, or pioneer yourself.
I take it your supply pump is providing similar pressure to an engine oil pump.
I take it your supply pump is providing similar pressure to an engine oil pump.
Milanoguy2
Automotive
- Dec 8, 2007
- 2
- 0
- 0
Well whatever you use it should be a synthetic lubricant that can stand very high temperatures.
Automatic transmissions are full of gears(shearing loads) and organic clutch material and I assume that ATF is formulated to meet those needs. The turbo is just a hot metal shaft running in a metal tube, so motor oil sounds pretty good to me.
Be sure to include a breather in the system.
Bye
Automatic transmissions are full of gears(shearing loads) and organic clutch material and I assume that ATF is formulated to meet those needs. The turbo is just a hot metal shaft running in a metal tube, so motor oil sounds pretty good to me.
Be sure to include a breather in the system.
Bye
- Thread starter
- #4
Thanks, guys, that's what I thought. OEM turbos can last many tens of thousands of miles on regular motor oil so I'm probably going to go with good old synthetic Mobil 1. The pump I have can maintain 60 psi for a much larger volume than the turbo needs; the reservoir does have a breather. I will be instrumenting things in this system (pump pressure, pre- and post- cooler temps) for a while after implementation just to get a feel for adequacy.
-Mike
-Mike
MargayKart79
Mechanical
Synthetic oil is the best and withstands the effects of coking. Thats a common side effect of turbos causing the oil to char from the heat. Id also watch out using that high of an oil pressure if you plan on running 60psi into the bearings. It will most likely cause the seals to leak. Typical pressure is 5-10psi with a gravity feed after the bearing since pressure is lost after the bearing.
kenre
Mechanical
- May 23, 2005
- 300
- 0
- 0
Maybe look at the specs of aircraft turbine oil? there formulated for high speed and heat.
Was told it couldnt be done, so
i went and did it!
Was told it couldnt be done, so
i went and did it!
- Thread starter
- #7
Re the 60 psi - there's a .060" restrictor in the feed line fitting to address the pressure issue. The drain is 1/2" line directly into a catch can with a breather from which the pump intake will draw from. A 10 micron filter and 80in2 2 row cooler w/ elec fan is inline with the system as well. This particular turbo is not coolant cooled so I hope to prevent coking by having the ECU run the turbo oiling for ~5 minutes after shutdown.
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