DIY oil cooler

boom · 05-03-2011, 09:53 PM

So there is a little known fact that the xi only comes with and a oil cooler if spec'd with the sport package AND the 18" wheel package. It is also limited to 135 mph without the 18s but the COBB AP took car of that...

Mine was spec'd with the sport package but not the 18" wheels so no oil cooler.

The options for aftermarket oil coolers are AR (smallish, really meant to augment the stock oil cooler, that I don't have), Stett (great option but pricey), and the place with the dual oil coolers that was going to be $2500 (Ultimate Racing??). Anyway, the Stett option is a grand but only if you have the factory setup. I did not and so it was around $1500 all said and done. I wasn't willing to spend that much and figured I could do it on my own for cheaper.

Step 1 - get an oil filter housing with thermostat capable of using an oil cooler. Mine was not setup for that and there is no way to make my stock housing work. I could have ordered the parts from Tischer but figured I'd try the salvage yards. Car-part.com does not list the oil filter housing as a separate item so I just called the yards that had long blocks for sale and asked. I would email this pic to make sure they had what I wanted.

This is my actual engine bay. Again, suck.

Luckily I found a shop that had the parts in Houston and $225 later I had the oil filter housing and thermostat.

Now the tricky part. How do you get that housing to fit aftermarket stuff?? Stett would not sell me their block off plate by itself and the $2500 oil cooler shop would not sell me their fitting either. Undaunted, decided to tap the thermostat housing with a 3/8" NPT fitting and run a 3/8" NPT to -8AN fitting. -8 AN is the same size that the Stett system uses and it sizes perfectly to 3/8" NPT. If you want -10, you need a bigger NPT thread. Tapping this thing is no small deal. I needed a vice, a friend, a big tap holder, and a break when it was all done. That's a big tap... If you already have an oil cooler, you just order the thermostat housing (iirc it's less than $100) and have it tapped.

Next up: mounting. The next several images are me looking at the space and identifying the right size cooler.
Fender liner

Liner removed

Close up of the brake duct with the cover on the mesh removed

half of the brake duct

Cover on the mesh - I removed this of course.

Duct out and fully assembled

There's a screw holding the duct in place in the front of the car that holds onto this tab.

The screw is on the opposite side of this plastic area. Sorry, best I could do.

The next four are of a box that I used to size up the area. It's tough to get an idea of how much space you have without something to reference by. I figured others might be able to use this.

I settled on an Earl's 34 row narrow cooler. This is not as wide as a SETRAB cooler so the capacity is lower but it's probably double the stock cooler. I bought my -8AN fittings, adapters, cooler, and lines from anplumbing.com which is the Earl's store. I spent a lot of time researching the parts I needed but went with the black Ano-tuff fittings and Pro-lite hose. All of the hoses have a 300 deg F tolerance and I didn't want to mess with the wire braid. I believe Stett uses this as well. They have great videos of how to make the AN fittings go on the braided lines. All in all it was great experience dealing with Earl's. They're always willing to answer questions and even took returns when the 60 deg fittings I bought didn't work for the space. I ended up with the 34 row narrow Earl's cooler, 7 ft of Pro-lite hose, two 3/8" NPT to -8AN adapters, two 45 deg -8AN fittings Ano-Tuff, and two 90 deg -8AN fittings Ano-Tuff.

Now we're on to mounting the thing. I have spent the most time with this part. It's is VERY time consuming and frustrating to try and develop a mounting strategy with home depot brackets and a dremel tool... I eventually just bought some steel angle that had holes and went to work. I'm sparing you the THREE different SETS of steel brackets made and just showing the final option. I made these, sanded and painted them and then glued cut up heater hose on the side that will contact the frame rail.

I'll be essentially squeezing the main frame rail with these two steel pieces and mounting the cooler to the outside steel. This way I don't have to drill anything into the car. That's my personal preference and others can do as they wish. I just didn't feel comfortable drilling there.

Next we have to make the cooler attach to the steel. I bought a $45 piece of Al angle and went to work with the dremel tool to make the upper and lower brackets. All coolers are made to work with brackets. YOu should not try to use the cooler top and bottom to secure the cooler. They are not strong enough. I got the idea for this design from the brackets that are actually sold for the Earl's cooler. I need it to extend out on one side so I just made mine. I have a love/hate relationship with my dremel tool now - especially since THREE separate SETS of Al brackets were fabbed before this one...

Note the notch. It plays an important role.

Bottom view

Side view

Cooler mounted: The notch holds the cooler in place so the squeezing steel brackets don't slide down the frame rail.

Top view from engine bay. I put heater hose around the bolts to cushion everything.

More views of the mounted cooler

Now with the lines

My fender liner was cut all to hell during several mock ups. I'm ordering a new one because these NUMEROUS cuts aren't necessary but this gives you an idea of the tightness.

This is a view without the fender liner of the bottom of the cooler when mounted. It's real close with the 34 row cooler.

Here's a shot from the front bumper mesh. I never removed the bumper during the whole thing.

More shots from the mesh. Note the notch doing its thing.

One thing is clear. I need a new Iphone with a better camera....

I painted my oil filter housing with caliper paint. I never understood why BMW left it bare Al as it just oxidizes and looks like shit. I followed this DIY for removing the intake manifold. http://www.e90post.com/forums/showthread.php?t=520922 but got to the part with this bracket and gave up.

http://img828.imageshack.us/img828/9327/img0718z.jpg

I could never get mine off and didn't want to spend too much time fooling with it.

Turns out you can remove the oil filter housing bolt but just lifting the intake manifold with all of the nuts and bolt removed. It's a pain but it does work.

I don't have pix of the install as time was short but here are some shots of the lines on my housing, etc.

More with a POS LED flashlight. Ooooh blue....

Not wanting my lines to rub. I'll be ordering an Al line holder from anplumbing to pretty this up.

I let the car idle for about 20 min while buttoning everything up and promptly beat the shit out of it. Oil temp never went over 245 and the cooler was hot. I'm guessing that's what my thermostat opens at. I was going to remove it altogether but read the Mr.5 thread about the housing and from it it seems without the thermostat, the oil won't go through the cooler. If anyone knows differently please post up. I don't like it that high but I doubt it'll go any higher...

No leaks

dwells · 05-03-2011, 10:40 PM

Wow, this is incredible. If I didn't suck at using my dremel I would try this, but alas, I kinda do suck at using it.

Great work!

boom · 05-04-2011, 08:05 AM

Quote:

Originally Posted by dwells

Wow, this is incredible. If I didn't suck at using my dremel I would try this, but alas, I kinda do suck at using it.

Great work!

THANKS! Give it a try. Just go slow and get the right tools. Makes all the difference.

dwells · 05-05-2011, 12:00 AM

Quote:

Originally Posted by boom

THANKS! Give it a try. Just go slow and get the right tools. Makes all the difference.

I'm gonna keep fighting with my dealership and BMWNA to see if I can get a free or discounted oil cooler retrofit (I have a 335i with sport package and 18" wheels option and no oil cooler), but chances are that'll go nowhere. I might just have to man up and follow this DIY once I have a free weekend and money for the parts and tools. I'll be sure to take a few pics and let you know how it goes.

TVTiZtiK · 05-05-2011, 01:18 AM

I'm probably going to at least attempt taking a crack at this.

This guide seems to be pretty thorough and clear. Thanks for taking the time to put this together, much appreciated.

boom · 05-08-2011, 06:02 PM

Quote:

Originally Posted by TVTiZtiK

I'm probably going to at least attempt taking a crack at this.

This guide seems to be pretty thorough and clear. Thanks for taking the time to put this together, much appreciated.

Thanks. Pm me for any advice. I spent a bunch of time on this.

dc5_champ88 · 09-25-2011, 05:50 PM

would u happen to have the part number for the oem oil filter housing and thermostat.

BTW GREAT WRITE UP!

boom · 07-01-2013, 06:10 AM

For an easier time connecting to the stock oil thermostat housing, buy this part:
http://store.bimmerworld.com/mobile/...kit-p1027.aspx
I wish I had known about it...

Pr335bob · 09-24-2013, 03:06 PM

hey thanks for the pics and info boom!
Im about to do this same project. but im looking to fit the oil cooler behind the kidney grills. my question is that oil thermostat housing conector u mention at the end, will it allow me to connect any oil cooler I see fit?

Pr335bob · 09-24-2013, 03:07 PM

i purchased the oil cooler housing and thermostat is that basically a take out and replace job? for the housing?

Davey303 · 06-10-2014, 01:36 PM

Quote:

Originally Posted by boom

For an easier time connecting to the stock oil thermostat housing, buy this part:
http://store.bimmerworld.com/mobile/...kit-p1027.aspx
I wish I had known about it...

Sorry to bump a super old thread, but would this piece prevent the need to do the tapping? I'm looking to build a setup off of your guide in the very near future.

Mick J · 09-05-2014, 02:06 PM

Bumping an old DIY again, but yes, Turner Motorsports also has the adapter instead of tapping the stock thermostat housing.

http://www.turnermotorsport.com/p-42...6-e82-e9x.aspx

ilicboris · 12-22-2015, 04:23 PM

Hate to bump an old thread, but I feel it deserves it with such great info. I do have a question though.

My 335xi came with no oil cooler and I immediately bought an oil filter housing with thermostat to retrofit one into my car. Found one on eBay for $80 shipped and was planning on going OEM route, but now I want aftermarket. I'm a little confused as to why tapping into the thermostat is still needed. Can't you just get the right size oil lines and any cooler and have it all plug and play?

Just wondering since my OFHG is finally leaking and I need to replace it and this is my time to upgrade. Thanks!

rkreimer10 · 10-23-2017, 11:32 AM

I am looking into putting an aftermarket oil cooler and thermostat on my car and was wondering if the OP could fix his pictures. There seems to be a lot of good information but photobucket has removed image hosting from their free account. Would love to see your set up.

05-03-2011, 09:53 PM	#1
boom My X5d tows my spec miata to the track. 74 Rep 1,254 Posts Drives: 2010 X5 35d Join Date: Sep 2009 Location: USA iTrader: (0)	DIY oil cooler So there is a little known fact that the xi only comes with and a oil cooler if spec'd with the sport package AND the 18" wheel package. It is also limited to 135 mph without the 18s but the COBB AP took car of that... Mine was spec'd with the sport package but not the 18" wheels so no oil cooler. The options for aftermarket oil coolers are AR (smallish, really meant to augment the stock oil cooler, that I don't have), Stett (great option but pricey), and the place with the dual oil coolers that was going to be $2500 (Ultimate Racing??). Anyway, the Stett option is a grand but only if you have the factory setup. I did not and so it was around $1500 all said and done. I wasn't willing to spend that much and figured I could do it on my own for cheaper. Step 1 - get an oil filter housing with thermostat capable of using an oil cooler. Mine was not setup for that and there is no way to make my stock housing work. I could have ordered the parts from Tischer but figured I'd try the salvage yards. Car-part.com does not list the oil filter housing as a separate item so I just called the yards that had long blocks for sale and asked. I would email this pic to make sure they had what I wanted. This is my actual engine bay. Again, suck. Luckily I found a shop that had the parts in Houston and $225 later I had the oil filter housing and thermostat. Now the tricky part. How do you get that housing to fit aftermarket stuff?? Stett would not sell me their block off plate by itself and the $2500 oil cooler shop would not sell me their fitting either. Undaunted, decided to tap the thermostat housing with a 3/8" NPT fitting and run a 3/8" NPT to -8AN fitting. -8 AN is the same size that the Stett system uses and it sizes perfectly to 3/8" NPT. If you want -10, you need a bigger NPT thread. Tapping this thing is no small deal. I needed a vice, a friend, a big tap holder, and a break when it was all done. That's a big tap... If you already have an oil cooler, you just order the thermostat housing (iirc it's less than $100) and have it tapped. Next up: mounting. The next several images are me looking at the space and identifying the right size cooler. Fender liner Liner removed Close up of the brake duct with the cover on the mesh removed half of the brake duct Cover on the mesh - I removed this of course. Duct out and fully assembled There's a screw holding the duct in place in the front of the car that holds onto this tab. The screw is on the opposite side of this plastic area. Sorry, best I could do. The next four are of a box that I used to size up the area. It's tough to get an idea of how much space you have without something to reference by. I figured others might be able to use this. I settled on an Earl's 34 row narrow cooler. This is not as wide as a SETRAB cooler so the capacity is lower but it's probably double the stock cooler. I bought my -8AN fittings, adapters, cooler, and lines from anplumbing.com which is the Earl's store. I spent a lot of time researching the parts I needed but went with the black Ano-tuff fittings and Pro-lite hose. All of the hoses have a 300 deg F tolerance and I didn't want to mess with the wire braid. I believe Stett uses this as well. They have great videos of how to make the AN fittings go on the braided lines. All in all it was great experience dealing with Earl's. They're always willing to answer questions and even took returns when the 60 deg fittings I bought didn't work for the space. I ended up with the 34 row narrow Earl's cooler, 7 ft of Pro-lite hose, two 3/8" NPT to -8AN adapters, two 45 deg -8AN fittings Ano-Tuff, and two 90 deg -8AN fittings Ano-Tuff. Now we're on to mounting the thing. I have spent the most time with this part. It's is VERY time consuming and frustrating to try and develop a mounting strategy with home depot brackets and a dremel tool... I eventually just bought some steel angle that had holes and went to work. I'm sparing you the THREE different SETS of steel brackets made and just showing the final option. I made these, sanded and painted them and then glued cut up heater hose on the side that will contact the frame rail. I'll be essentially squeezing the main frame rail with these two steel pieces and mounting the cooler to the outside steel. This way I don't have to drill anything into the car. That's my personal preference and others can do as they wish. I just didn't feel comfortable drilling there. Next we have to make the cooler attach to the steel. I bought a $45 piece of Al angle and went to work with the dremel tool to make the upper and lower brackets. All coolers are made to work with brackets. YOu should not try to use the cooler top and bottom to secure the cooler. They are not strong enough. I got the idea for this design from the brackets that are actually sold for the Earl's cooler. I need it to extend out on one side so I just made mine. I have a love/hate relationship with my dremel tool now - especially since THREE separate SETS of Al brackets were fabbed before this one... Note the notch. It plays an important role. Bottom view Side view Cooler mounted: The notch holds the cooler in place so the squeezing steel brackets don't slide down the frame rail. Top view from engine bay. I put heater hose around the bolts to cushion everything. More views of the mounted cooler Now with the lines My fender liner was cut all to hell during several mock ups. I'm ordering a new one because these NUMEROUS cuts aren't necessary but this gives you an idea of the tightness. This is a view without the fender liner of the bottom of the cooler when mounted. It's real close with the 34 row cooler. Here's a shot from the front bumper mesh. I never removed the bumper during the whole thing. More shots from the mesh. Note the notch doing its thing. One thing is clear. I need a new Iphone with a better camera.... I painted my oil filter housing with caliper paint. I never understood why BMW left it bare Al as it just oxidizes and looks like shit. I followed this DIY for removing the intake manifold. http://www.e90post.com/forums/showthread.php?t=520922 but got to the part with this bracket and gave up. http://img828.imageshack.us/img828/9327/img0718z.jpg I could never get mine off and didn't want to spend too much time fooling with it. Turns out you can remove the oil filter housing bolt but just lifting the intake manifold with all of the nuts and bolt removed. It's a pain but it does work. I don't have pix of the install as time was short but here are some shots of the lines on my housing, etc. More with a POS LED flashlight. Ooooh blue.... Not wanting my lines to rub. I'll be ordering an Al line holder from anplumbing to pretty this up. I let the car idle for about 20 min while buttoning everything up and promptly beat the shit out of it. Oil temp never went over 245 and the cooler was hot. I'm guessing that's what my thermostat opens at. I was going to remove it altogether but read the Mr.5 thread about the housing and from it it seems without the thermostat, the oil won't go through the cooler. If anyone knows differently please post up. I don't like it that high but I doubt it'll go any higher... No leaks
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05-03-2011, 10:40 PM	#2
dwells ಠ_ಠ 74 Rep 1,539 Posts Drives: Monaco Blue 335i coupe Join Date: Nov 2010 Location: New England iTrader: (6)	Wow, this is incredible. If I didn't suck at using my dremel I would try this, but alas, I kinda do suck at using it. Great work! __________________ \| 335i coupe \| Monaco Blue \| JB4 G5 ISO \| Style 313M \| Huper 40% tint \| Aero lip \| CSL trunk spoiler \| M3 sideskirts \| Paint-matched grilles \| Painted reflectors \| GP Thunder II angel eyes \| Smoked LED sidemarkers \| Self-coded \|
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05-05-2011, 01:18 AM	#5
TVTiZtiK Registered 4 Rep 4 Posts Drives: '07 Monaco Blue E92 Join Date: Feb 2011 Location: Scottsdale, AZ iTrader: (0)	I'm probably going to at least attempt taking a crack at this. This guide seems to be pretty thorough and clear. Thanks for taking the time to put this together, much appreciated.
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09-25-2011, 05:50 PM	#7
dc5_champ88 Captain 24 Rep 666 Posts Drives: 2007 BMW 335i Join Date: Oct 2010 Location: Maryland iTrader: (5) Garage List 2007 BMW 335i [0.00]	would u happen to have the part number for the oem oil filter housing and thermostat. BTW GREAT WRITE UP! __________________ Current: 07 e92 335i: JB4, AA Catless DP, Big Tom FMIC, CP-e Full Exhaust, Injen Intake, Type-S BOV, Meth Previous: 03 Acura RSX-S: Boosted 400WHP (SOLD)
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07-01-2013, 06:10 AM	#8
boom My X5d tows my spec miata to the track. 74 Rep 1,254 Posts Drives: 2010 X5 35d Join Date: Sep 2009 Location: USA iTrader: (0)	For an easier time connecting to the stock oil thermostat housing, buy this part: http://store.bimmerworld.com/mobile/...kit-p1027.aspx I wish I had known about it...
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09-24-2013, 03:06 PM	#9
Pr335bob Captain 38 Rep 753 Posts Drives: Black on black e92 Join Date: Oct 2011 Location: Puerto Rico USA iTrader: (0)	hey thanks for the pics and info boom! Im about to do this same project. but im looking to fit the oil cooler behind the kidney grills. my question is that oil thermostat housing conector u mention at the end, will it allow me to connect any oil cooler I see fit?
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09-24-2013, 03:07 PM	#10
Pr335bob Captain 38 Rep 753 Posts Drives: Black on black e92 Join Date: Oct 2011 Location: Puerto Rico USA iTrader: (0)	i purchased the oil cooler housing and thermostat is that basically a take out and replace job? for the housing?
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09-05-2014, 02:06 PM	#12
Mick J Private 2 Rep 76 Posts Drives: 08 - E90 335i Join Date: Apr 2012 Location: NOLA iTrader: (5)	Bumping an old DIY again, but yes, Turner Motorsports also has the adapter instead of tapping the stock thermostat housing. http://www.turnermotorsport.com/p-42...6-e82-e9x.aspx __________________ Gone but not forgotten: 447WHP - 458WTQ: JB4 G5 ISO / BB-BMS flash / AR DP / ETS 5in FMIC / ER chargepipe & Tial BOV / BMS 2.2gal meth / AFE intake / BMS Thermostat / BMS OCC / Custom exhaust - removed resonators, 3.8" Cyba tips, single center cutout VMR V710 19x8.5 ET20 & 19x10 ET25 / Bridgestone S-04 Pole Positions 245/35/19 & 285/30/19
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12-22-2015, 04:23 PM	#13
ilicboris First Lieutenant 77 Rep 334 Posts Drives: 2009 E90 335xi Join Date: Nov 2014 Location: Nebraska, USA iTrader: (0)	Hate to bump an old thread, but I feel it deserves it with such great info. I do have a question though. My 335xi came with no oil cooler and I immediately bought an oil filter housing with thermostat to retrofit one into my car. Found one on eBay for $80 shipped and was planning on going OEM route, but now I want aftermarket. I'm a little confused as to why tapping into the thermostat is still needed. Can't you just get the right size oil lines and any cooler and have it all plug and play? Just wondering since my OFHG is finally leaking and I need to replace it and this is my time to upgrade. Thanks!
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10-23-2017, 11:32 AM	#14
rkreimer10 New Member 12 Rep 26 Posts Drives: e46 Join Date: Jan 2017 Location: frozen tundra iTrader: (0)	I am looking into putting an aftermarket oil cooler and thermostat on my car and was wondering if the OP could fix his pictures. There seems to be a lot of good information but photobucket has removed image hosting from their free account. Would love to see your set up.
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