Oil Cooler, Heat Exchanger, or none for Swaps? Heat issues? Warmup Issues?

Straypoet

Well-known member
Joined
Jun 17, 2020
Location
Florida
TDI
BHW 2.0, soon to be in my Wrangler.
A thread that I hope will be helpful for others as well.

I would like to gather the wisdom on choices for oil coolers, or heat exchangers specifically relating to swaps.
I have found a few threads here that have some of this information, but I think a central location would be helpful for me, and I want to gather other solutions so that I can make better choices for my setup.

Background; I am working on a BHW swap into a longitudinal 4wd vehicle, and am planning to install an oil filter relocation plate, but that removes the stock heat exchanger.

1: I know that the original heat exchanger performs 2 functions, it brings the oil up to normal operating temp more quickly, and it also maintains the correct operating temp of the oil under load.

2: Are there any swaps that use no cooler or heat exchanger at all? do you have problems with oil temp? Do you monitor oil temp?

3: Anyone use just an oil cooler? Why did you go this route?

4: Anyone use an external heat exchanger?

5: Has any one had issues with slow warmups?

6: If you kept the original system what made you keep it? worries like I have outlined above?


Thank you everyone who comments. :)
 

TurboABA

Veteran Member
Joined
Jul 24, 2010
Location
Kitchener, ON
TDI
RIP-2010 Jetta 6spd 2014 Touareg Execline
I don't have a swap, so take this with a grain of salt.
Why do you even care about warmup in FL?
Also, your cooling requirements will vary with the intended use of the vehicle. A daily driver will have different needs than an overlander, just as a tow vehicle will differ.
The best advice I can give you is think about your intended use so that you can build something that works best for your situation.
 
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Straypoet

Well-known member
Joined
Jun 17, 2020
Location
Florida
TDI
BHW 2.0, soon to be in my Wrangler.
I don't have a swap, so take this with a grain of salt.
Why do you even care about warmup in FL?
Also, your cooling requirements will vary with the intended use of the vehicle. A daily driver will have different needs than an overlander, just as a tow vehicle will differ.
The best advise I can give you is think about your intended use so that you can build something that works best for your situation.
The vehicle may be in Florida today, but I fully expect to be using in winter in the north as well. So certainly something I want to consider, but also this applies to Florida in the summer, as the exchanger also cools oil.
Since others have eliminated this heat exchanger in their swaps (those that use the filter relocation plates) I think getting their experiences would help me to know if I do need auxiliary oil cooling/warming.
 

Koehn

Well-known member
Joined
Oct 25, 2018
Location
Vancouver, BC
TDI
2005 A4 Avant Quattro 6-Speed (AVF)
Why not just run an oil cooler with a thermostat? Other than the price, that is.

I found this one mentioned on a Porsche 914 forum after a quick Google search. If it works for people racing air-cooled engines, I imagine it would work fine for a TDI. You can even choose the operating temp and port size.
 

greengeeker

Vendor
Joined
Feb 8, 2006
Location
Cambridge, MN
TDI
2002 Jetta GLS
For my TDI ranger swap I went with the stock ALH oil cooler. It works fine for moving the truck around empty but oil temps would climb if I was doing sustained power output (towing heavy, towing something with terrible aero, etc). They would climb so much so that oil pressure started dropping. As stated, your intended use should dictate what steps taken with your hardware. I would say for your climate, a simple air to oil heat exchanger is all that is needed.
 

iwannajettatdi

Veteran Member
Joined
Jun 17, 2003
Location
Salem, OR
TDI
2015 Brilliant Black Audi Q5 3.0TDI, 2014 Tempest Blue metallic Jetta Sportwagen TDI, 2002 Blue Eurovan Weekender BHW TDI
From what I understand, the BHW is the biggest available on our NA TDIs. Other than running it through an air cooler like a small fuel or transmission cooler, I'm not sure theres an easy/cheap option.

Another thought, would a spare EGR cooler work? The coolant hoses would plug right in, and you'd just need to figure out oil routing and flanges to the exhaust ports. That's probably the cheapest fluid to fluid cooler without much work.
 

Straypoet

Well-known member
Joined
Jun 17, 2020
Location
Florida
TDI
BHW 2.0, soon to be in my Wrangler.
Why not just run an oil cooler with a thermostat? Other than the price, that is.

I found this one mentioned on a Porsche 914 forum after a quick Google search. If it works for people racing air-cooled engines, I imagine it would work fine for a TDI. You can even choose the operating temp and port size.
I like that idea. Someone suggested using a radiator made for an automatic vehicle, because they have a built in oil cooler. I may go that route. Having the thermostat control flow through the oil cooler is a great idea.
 

PickleRick

Veteran Member
Joined
Nov 29, 2017
Location
Greenville sc
TDI
05 GLS BHW sedan 5 speed conversion. BHW Carver SantaCruz in progress
In the marine world the power steering pump is cooled using raw water via a cooler plumbed inline on the raw water intake hose. About a 1.25 to 1.5 ID hose in many applications. These can be found cheaply all over eBay and Amazon new and used, referred to as heat exchangers. Mercruiser will likely be the cheapest and most common.

This could be plumbed into a radiator hose in an automotive application. They are compact.

If additional cooling is required running it in an additional loop thru the radiator is also a good idea.
 

Straypoet

Well-known member
Joined
Jun 17, 2020
Location
Florida
TDI
BHW 2.0, soon to be in my Wrangler.
This could be plumbed into a radiator hose in an automotive application. They are compact.
This would essential replicate the heat exchanger that is built into the bottom of the BHW oil filter housing.
I like that.
 
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