HV Transaxle cooler/filter

IFixEm · 05-16-2006, 12:19 AM

[attachmentid=3467]
There was some discussion recently here and offline into the feasibility of a transmission cooler. I made one and it works but I am not totaly convinced of the need at this point (lack of unit failures). I did make an added bonus to the system with the use of an external sediment filter. The filter is clear so fluid color and condition can be easilly assessed during the 5k service. The installation time is about 40 minutes with no special tools, and only basic mechanical aptitude. It's on par with an EV switch. The ambient temps today were 75ish, low humidity. Test vehicle, 01 prius 74K. After a 45 minute road test at lunch and another after work, it seemd to cool MG2 by about 8-15 degrees over yesterday's run. Not very scientific I know. The oil is definately cooler...130 going out, 95 going in using digital thermometer. Does it work to keep MG2 cool? I think so. Is the oil cooler? Yes. Is it easier to keep clean? Yes. If the filter plugs will my gears starve for oil? No. Wiil the oil get to cold in winter? No.

Some initial pics.........
[attachmentid=3468]

Run the lines behind the radiator support.

[attachmentid=3469]

There was room for a filter so...

[attachmentid=3470]

Oil pump location, 4 screws removed to take splash shield out

[attachmentid=3476]

Version 1.0a

[attachmentid=3471]

This filter requires changing, and the oil needs serviced. Visual inspection at a 5k intervals prevent the "crude oil" look some Prius have experienced.

[attachmentid=3472]

This oil is clean.

[attachmentid=3473]

Oil will flow thru this drive shaft and help cool MG2 PM and bearings.

[attachmentid=3474]

Oil exits the planet carrier shaft and lubes the pinions (port is hidden from view), and MG1 sun gear, inner and outer bushings.

[attachmentid=3475]

Oil level is about 20mm below (to the right) of my hand and helps cool the windings, and lubricate the differential assembly and SDC. Your Input requested.

Regards, Mike

**efusco** · 05-16-2006, 06:19 AM

Mike,
As I understand your modification you're simply using the existing oil pump to pump the oil through MG2. That makes sense for convenience. But, as you mentioned, it seems that this might be nothing more than adding a belt when already wearing suspenders. At least with my '04 Prius MG2 temps seem to stay within a reasonable range...though I haven't been able to monitor those temps during the peak of summer heat.

Now, one issue brought up amongst the PHEV crowd has been that the oil pump is run via the ICE. When they're running for longer distances in EV mode there is no oil being pumped and there's some concern that over long distances they could be doing some damage to the system as the Prius wasn't designed to be a long range EV.

One individual I know has created a seperate electrical pump that keeps the MG lubed via the 12v battery (though with the existing coolant system, not via a seperate radiator). If I had a suggestion I guess that would be it. Look at MG2 temps (and inverter temps) over longer EV runs before and after an electric coolant pump is installed...I suspect your variance from baseline will be much greater.

viking31 · 05-16-2006, 09:38 AM

Great idea but I would be concerned about a few items regarding the installation.

I would prefer steel braided hoses with flare nut to nipple connections rather than hose clamps. These oil lines are important and unlike a radiator hose failure, failure of these lines could lead to extensive damage to the components it serves well before the operator of the vehicle is aware of the failure. The clear filter is also unique but again as with the hoses I would prefer at least a steel shield of some sorts to protect the plastic filter. In addition, the filter should also have some sort of bypass mechanism in case of clogging or excessive load.

Rick
2006 #4

FireEngineer · 05-16-2006, 10:02 AM

Mike, did you add extra oil to the transaxle to account for the oil in the cooler? If so how did that affect the transaxel breather when the oil was not running in the cooler-EV mode?

Wayne

IFixEm · 05-16-2006, 01:20 PM

Quote:

Mike,
"As I understand your modification you're simply using the existing oil pump to pump the oil through MG2. That makes sense for convenience. But, as you mentioned, it seems that this might be nothing more than adding a belt when already wearing suspenders. At least with my '04 Prius MG2 temps seem to stay within a reasonable range...though I haven't been able to monitor those temps during the peak of summer heat."

I agree. MG2 already seems to run 15* cooler than MG1. Now it's 20-30*. Inverter temps seem to spike easy, but come right back down. Circulating the oil should help to cool the oil and thus lower winding temps, but probably will have no affect on case or inverter temps. It's just not that big of a system. Belt/suspenders is funny, I was thinking maytag repair guy that came up with a better dryer sheet. I'm not sure this qualifies for belt status because belts work by themselves.

Quote:

"Now, one issue brought up amongst the PHEV crowd has been that the oil pump is run via the ICE. When they're running for longer distances in EV mode there is no oil being pumped and there's some concern that over long distances they could be doing some damage to the system as the Prius wasn't designed to be a long range EV."

I think (FWIW) that extended ev will not be an issue. The diff carrier sits immersed in oil, so the SDC should sling oil onto the Planet assy anytime the veh is moving ice on or off.

Quote:

"One individual I know has created a seperate electrical pump that keeps the MG lubed via the 12v battery (though with the existing coolant system, not via a seperate radiator). If I had a suggestion I guess that would be it. Look at MG2 temps (and inverter temps) over longer EV runs before and after an electric coolant pump is installed...I suspect your variance from baseline will be much greater."

[/quote]
Looks like a far better idea for cooling, but I like being able to see the oil, sticking a finger in the hole is hard to get a good color reading. You have probably more time looking at prius data than anyone else including Toyota techs (me). We are after specific problems or working on camrys. I especially appreciate your input Doc.
Regards, Mike

Quote:

Mike, did you add extra oil to the transaxle to account for the oil in the cooler? If so how did that affect the transaxel breather when the oil was not running in the cooler-EV mode?

Wayne

The cooler is not higher than OEM oil level, so drainback should not be an issue. It took .6 quarts extra.
Regards, Mike

Quote:

Great idea but I would be concerned about a few items regarding the installation.

I would prefer steel braided hoses with flare nut to nipple connections rather than hose clamps. These oil lines are important and unlike a radiator hose failure, failure of these lines could lead to extensive damage to the components it serves well before the operator of the vehicle is aware of the failure. The clear filter is also unique but again as with the hoses I would prefer at least a steel shield of some sorts to protect the plastic filter. In addition, the filter should also have some sort of bypass mechanism in case of clogging or excessive load.

Rick
2006 #4

I went sorta cheap on the first one because I bought the parts for my customer ( sans oil) so I went with rubber oil hose. There is a bypass mod in the pump so that if a line got pinched you will not starve it for oil. I used a plastic A/T valve body check ball from old previa vans and the dual stage sping found under the flint in a bic lighter. I was quite scared of this actually, starving the guts that is.
Regards, Mike

hdrygas · 05-17-2006, 02:10 AM

Very Very nice. How might this fit in with my radiator blocker, I have not yet been through a summer to monitor the temps on the inverters and windings. I am taking the blocker off tomorrow even though in the past several warm days I have not seen a change over the winter temps with everything blocked up. I need to know the "norms" for summer driving. I am looking for a few 90 degree days. OK go ahead and laugh you folks in the sunbaked south land, but between the mild climate and the radiator blocker and the block heater I may yet give you a run for your money. I just need to know how hard to push things and what the normal summer range is. I would appreciate input from people with the Can View with OBD II mod on the inverter and winding temps in summer conditions, your summer not mine!

sub3marathonman · 05-17-2006, 09:21 AM

<div class='quotetop'>QUOTE(IFixEm @ May 16 2006, 12:19 AM) [snapback]256121[/snapback]</div>

Quote:

[attachmentid=3470]

Oil pump location, 4 screws removed to take splash shield out

[attachmentid=3476]

Version 1.0a

Regards, Mike
[/b]

I just had a question about "Version 1.0a." How did you go from the top picture of the original oil pump to the second picture of "Version 1.0a" with the oil lines attached? Were there two plugs that you removed and then replaced them with the hose fittings?

grasshopper · 05-17-2006, 12:45 PM

<div class='quotetop'>QUOTE(hdrygas @ May 17 2006, 02:10 AM) [snapback]256709[/snapback]</div>

Quote:

I have not yet been through a summer to monitor the temps on the inverters and windings. I am taking the blocker off tomorrow even though in the past several warm days I have not seen a change over the winter temps with everything blocked up. I would appreciate input from people with the Can View with OBD II mod on the inverter and winding temps in summer conditions, your summer not mine!
[/b]

How are you monitoring your temps? You mention Can View with OBD II mod on the inverter and winding temps. I don’t know what all that means. Are you able to see these temps on the MFD, or is it this OBD II mod that allows you to see the temps? I want to have temp gauges for the ICE oil and transmission fluids. Do I need to just have some gauges installed? Are there sensors already installed or is that something I need to get also. Will this OBD II mod do all of that for me? Obviously I don’t know what an OBD II mod is and with just a package #3, maybe I don’t have all I need to install it anyway?
I pull a trailer and feel that I defiantly need to monitor the temp’s real time. I have been following this subject, but I admit that I don’t know enough to understand what ya’ll are doing. Can someone take the time to explain some of this to me, or just how to install some gauges?

IFixEm · 05-17-2006, 06:33 PM

<div class='quotetop'>QUOTE(sub3marathonman @ May 17 2006, 06:21 AM) [snapback]256800[/snapback]</div>

Quote:

I just had a question about "Version 1.0a." How did you go from the top picture of the original oil pump to the second picture of "Version 1.0a" with the oil lines attached? Were there two plugs that you removed and then replaced them with the hose fittings?
[/b]

There is one plug (bolt) for checking oil presure...all blistering 5-13 psi of it. I replaced that with a cold start injector bolt from a 22re or 3vze I'm not sure. I then put a cold start fuel line on it and connected a hose. The second hose home needed drilled and tapped to accept my new fitting, modified an internal pump passage and there it is. First one in captivity. It cost me $7 for the bolt, 5 for a fitting, the cold start line was floating around here. The cooler and hoses were $36. Pretty cheap mod...wish it worked better, but it still has some upsides to it I think. The customer is a great guy, and has multiple hybrids. I think this Prius was one of the first the dealer sold. I appreciate everyones input.
Regards, Mike

hobbit · 05-17-2006, 10:53 PM

I was gonna say, outout pressure from that pump is pretty
minimal so it seems unlikely you're going to blow hoses off the
fittings from that. Sure, flare fittings for high-pressure stuff,
but here, the oil just lazily circulates.
.
The mod target is still a running car, right? As opposed to the
toasted-MG2 transaxle you've got apart but can use to model some
of this stuff? It's great that you've got that to play with and
can keep taking all those wonderful pictures.
.
Did you ever figure out *what* toasted that motor, BTW?
.
_H*

05-16-2006, 12:19 AM	#1
IFixEm Join Date: Oct 2005 Location: a gallon south of Microsoft Posts: 69 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	[attachmentid=3467] There was some discussion recently here and offline into the feasibility of a transmission cooler. I made one and it works but I am not totaly convinced of the need at this point (lack of unit failures). I did make an added bonus to the system with the use of an external sediment filter. The filter is clear so fluid color and condition can be easilly assessed during the 5k service. The installation time is about 40 minutes with no special tools, and only basic mechanical aptitude. It's on par with an EV switch. The ambient temps today were 75ish, low humidity. Test vehicle, 01 prius 74K. After a 45 minute road test at lunch and another after work, it seemd to cool MG2 by about 8-15 degrees over yesterday's run. Not very scientific I know. The oil is definately cooler...130 going out, 95 going in using digital thermometer. Does it work to keep MG2 cool? I think so. Is the oil cooler? Yes. Is it easier to keep clean? Yes. If the filter plugs will my gears starve for oil? No. Wiil the oil get to cold in winter? No. Some initial pics......... [attachmentid=3468] Run the lines behind the radiator support. [attachmentid=3469] There was room for a filter so... [attachmentid=3470] Oil pump location, 4 screws removed to take splash shield out [attachmentid=3476] Version 1.0a [attachmentid=3471] This filter requires changing, and the oil needs serviced. Visual inspection at a 5k intervals prevent the "crude oil" look some Prius have experienced. [attachmentid=3472] This oil is clean. [attachmentid=3473] Oil will flow thru this drive shaft and help cool MG2 PM and bearings. [attachmentid=3474] Oil exits the planet carrier shaft and lubes the pinions (port is hidden from view), and MG1 sun gear, inner and outer bushings. [attachmentid=3475] Oil level is about 20mm below (to the right) of my hand and helps cool the windings, and lubricate the differential assembly and SDC. Your Input requested. Regards, Mike __________________ coolest prius I ever worked on....department of corrections, EV for silent run, DRL disabled, passenger seat removed, shotgun mount installed. [size=1]

05-16-2006, 06:19 AM	#2
efusco Troll Slayer Join Date: Nov 2003 Location: Nixa, MO Posts: 14,247 My Car: 2004 Prius Package: #9 Nominated 1 Time in 1 Post TOTM Awards: 0 Friends: 24	Mike, As I understand your modification you're simply using the existing oil pump to pump the oil through MG2. That makes sense for convenience. But, as you mentioned, it seems that this might be nothing more than adding a belt when already wearing suspenders. At least with my '04 Prius MG2 temps seem to stay within a reasonable range...though I haven't been able to monitor those temps during the peak of summer heat. Now, one issue brought up amongst the PHEV crowd has been that the oil pump is run via the ICE. When they're running for longer distances in EV mode there is no oil being pumped and there's some concern that over long distances they could be doing some damage to the system as the Prius wasn't designed to be a long range EV. One individual I know has created a seperate electrical pump that keeps the MG lubed via the 12v battery (though with the existing coolant system, not via a seperate radiator). If I had a suggestion I guess that would be it. Look at MG2 temps (and inverter temps) over longer EV runs before and after an electric coolant pump is installed...I suspect your variance from baseline will be much greater. __________________ Evan E. Fusco, MD Seaside 04BC9/OEM EVb/NAV & auto-BT/XM Radio, CAN-View, Shark Fin, BT Stiff. Plate, Skid Plate & Strut Support

05-17-2006, 02:10 AM	#6
hdrygas Senior Member Join Date: May 2004 Location: Olympia Wa Posts: 3,650 My Car: 2004 Prius Package: #9 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Very Very nice. How might this fit in with my radiator blocker, I have not yet been through a summer to monitor the temps on the inverters and windings. I am taking the blocker off tomorrow even though in the past several warm days I have not seen a change over the winter temps with everything blocked up. I need to know the "norms" for summer driving. I am looking for a few 90 degree days. OK go ahead and laugh you folks in the sunbaked south land, but between the mild climate and the radiator blocker and the block heater I may yet give you a run for your money. I just need to know how hard to push things and what the normal summer range is. I would appreciate input from people with the Can View with OBD II mod on the inverter and winding temps in summer conditions, your summer not mine! __________________ Belle, a Millennium Silver '04 BC #9 "Becoming one with my Prius, ICE on ICE off" Belle has been passed on to my daughter. I have a new silver Prius 08. No name yet we have just met but not been introduced.

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05-16-2006, 09:38 AM	#3
viking31 Senior Member Join Date: Oct 2005 Location: West Central Florida Posts: 457 My Car: 2006 Prius Package: #4 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Great idea but I would be concerned about a few items regarding the installation. I would prefer steel braided hoses with flare nut to nipple connections rather than hose clamps. These oil lines are important and unlike a radiator hose failure, failure of these lines could lead to extensive damage to the components it serves well before the operator of the vehicle is aware of the failure. The clear filter is also unique but again as with the hoses I would prefer at least a steel shield of some sorts to protect the plastic filter. In addition, the filter should also have some sort of bypass mechanism in case of clogging or excessive load. Rick 2006 #4

05-16-2006, 10:02 AM	#4
FireEngineer Senior Member Join Date: Oct 2004 Location: SW-Side of Chicago, IL Posts: 792 My Car: 2005 Prius Package: #6 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 4	Mike, did you add extra oil to the transaxle to account for the oil in the cooler? If so how did that affect the transaxel breather when the oil was not running in the cooler-EV mode? Wayne

05-17-2006, 10:53 PM	#10
hobbit Senior Member Join Date: Mar 2005 Location: Bahstahn Posts: 2,989 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	I was gonna say, outout pressure from that pump is pretty minimal so it seems unlikely you're going to blow hoses off the fittings from that. Sure, flare fittings for high-pressure stuff, but here, the oil just lazily circulates. . The mod target is still a running car, right? As opposed to the toasted-MG2 transaxle you've got apart but can use to model some of this stuff? It's great that you've got that to play with and can keep taking all those wonderful pictures. . Did you ever figure out what toasted that motor, BTW? . _H*