oil coolers!! (kinda long)

plain fan · 11-21-2001, 01:18 PM

Let me preface my question with a little history. Took the 911 to the mechanic to have valves adjusted and the oil return tubes replaced. Got a call from them the next day saying that my engine mounted cooler was leaking. I thought that maybe the o rings were leaking but that wasn't the problem. Anyway I had them replace the oil cooler with a used one and they gave me the old one so I can see if it can be fixed.
Here is my question, last night I was reading Bruce Andersons book and noticed that the 964/993 engines don't have an engine mounted oil cooler. Has anyone tried making this change on the earlier engines? It says that Porsche also made some other cooling related changes such as the piston cylinders and the fan, but then they put that noise shield on the engine, wouldn't that negate any cooling improvements? I am perfectly happy with my mechanic and the work they do, but it got me thinking....anyone try this or hear about this?

Bill Verburg · Bill Verburg's Garage

The engine mounted cooler on any 911 can be removed with the following caveats

the front cooler will need to be larger to compensate from the reduced cooling at the engine
the engine will be more prone to overheating in traffic because there is no longer forced inductive cooling
item 2 above can be obviated by using a fan on the fender mounted cooler
a custom oil line will need to be fabricated on all engines. the 964 and 993 already have a threaded fitting which should be utilized
pre 964 engines will need 993 107 215 02 and a few additional bolts and seals to replace the cooler

plain fan · 11-21-2001, 01:52 PM

What is this custom oil line and where would it go to? I know about the 993/964 parts, the book said that Porsche mounted another oil filter in place of the oil cooler and moved the oil pressure/temp sensors to the same place. Have you tried doing this conversion or seen it in place in a pre 964 car? I would think that the oil cooler being relocated to the front of the car with fans would be ideal, it wouldn't be near the hot engine and when moving the air, I assume, would be cooler.

ChrisBennet · ChrisBennet's Garage

I think my oil cooler is leaking and I was thinking of removing it and going with the Kokeln fender mounted oil cooler.
http://www.lindseyracing.com
Does anyone know anything about this cooler?
-Chris

Jack Olsen · 11-21-2001, 03:34 PM

Jeez, the grass is always greener, I guess. Guys with 3.6s swapped in often add a Carrera engine-based cooler in an attempt to keep temps under control. Adding an expensive modification to the front of the car to fix a leak in the back strikes me as 'doing it the hard way.'

Fender-based coolers -- without ducting and venting and fans -- are not as efficient as the engine-housed models. Good bumper-mounted coolers require bigger front valences or cutting and welding. Bigger fender based coolers also require cutting and welding. Trust me, I've been there.

plain fan · 11-21-2001, 03:51 PM

Well, if an engine mounted cooler is better than the fender mounted cooler, why did Porsche make the change? You guys that make the switch, is engine temp that large of an increase? I'm not considering making the change on the 911, but it might be an interesting switch if the need ever arose or I decided to build a track car.

Bill Verburg · Bill Verburg's Garage

The line can be seen in this pic exiting the lower block thence to the oil tank. on a 964 an ~6" ss tube is welded to the oem fitting, stocks 'S' hose to tank connects to the ss tube.

On a 3 or 3.2 liter the oil cooler mount can be seen in the second pic the top 2 holes will need to be bridged(with gallery 993 107 215 020) the bottom hole is where the custom line to the oil tank goes. Stock the pipe is integral with the cooler. But the 964 or 993 set up can be adapted with some work.

993 has an oil filter console(993 107 057 00) mounted here. with the return line exiting beneath it.

As with many 911 mods its probobaly best to stick with the stock cooler in the stock location.

Early_S_Man · 11-21-2001, 04:04 PM

I don't think you could get by with less than TWO fan-assisted coolers up front, and they better be BIG ONES, Turbo-sized or larger!!! With EXTRA HOLES and ducting, to boot!

Suddenly, a used cooler on the engine begins to look pretty good, huh?

Doug Zielke · 11-21-2001, 04:06 PM

Hey PF,
Not trying to give you a fit, but I hope the used cooler they sold you was nice and clean inside. Oil coolers are kinda like tooth-brushes, if ya get my drift.

plain fan · 11-21-2001, 04:16 PM

Thanks for all the info, I'm not planning on making the change I was curious, like I said for a track car it may not be that bad of an idea. Of course I was thinking about a very large cooler with multiple fans to supply the air.
The shop that works on my 911 only works on Porsches and has been in business for a long time. I've never had a problem with them and they guarantee their work. They rarely replace with a used or rebuilt part unless they know the source and once again the used/rebuilt sources offer guarantees of their owns. I thought about the used oil cooler and I trust my mechanics judgement, like I said they guarantee their work. They've fixed things before w/o charge if they should have caught the problem the first time around or if they were working on something else and noticed but did not notify me or fix the problem when they saw it. Thanks to all again. The track car I'm considering won't be built for some time, but I know of a 914 that is sitting. Give it a "six-fix" flares, upgraded suspension, lightweight body parts etc....and have some real fun around the track and of course I'll drive it to the event!