Right before DGRR this year I was replacing the coolant. I also wanted to get the car up on stands to do a brake flush etc, getting ready for the event. Long story short as I was using my floor jack under the engine crossmember, it slipped off the jack and caught the oil cooler. It crumpled the cooler a bit. When I started driving it around I noticed it would get hot during standing traffic ( I had also redone the cooling fans to be on temp sensor ) so figured it was an adjustment needed on the fan run durations. Anyway, when I got to DGRR I had to run my heater when in heavy traffic to keep the temp gauge from going past the halfway point. Worrisome but I worked around it and didn't really have any negative affect on my DGRR fun. I got home and adjusted the fan sensor but it still was getting hot (better but not right). So that is when I decided to replace the OEM oil cooler with a reasonably priced aftermarket cooler.

This post is about that project. I got the cooler from SummitRacing and the new line kit from EvilEnergy. The cooler has no internal tstat like the OEM cooler but I can live with that since I don't run this car much in cold weather and I generally warm it up anyway before heading out. I know there are debates and drawbacks claimed with doing this but its really not that big a deal (unless you are driving in really cold weather, like below 30F). I don't have a oil temp gauge setup because I want to keep the interior original. I do have an infrared instant read thermometer which I use all the time for AC work and cooling issues in general. So I will be checking this out with that for sure.

I'll list links to the parts I ordered at the end of this post.

The cooler is a dual pass with -10 AN fittings. I had seen mention of others ( @j_tso ) using this cooler with success. I wanted to replace the OEM cooler and keep the OEM radiator for now.

I had hopes of reusing my RacingBeat oil lines but when I got it mounted up I could see I needed different lines. I chose the Evil Energy kit on Amazon because some other folks I know had used their stuff with great success. I chose the -10 AN lines and fittings using the PTFE hose at the core of the lines. Two reasons for this; PTFE has a much higher burst pressure and no real new tools needed to make the lines.

The steps for doing this were the following (I'll get into details on subsequent posts here with pictures)

1. Remove under tray, grill, and battery.

2. Remove the old cooler and lines.

3. Fab up mounts for the new cooler.

4. Mount new cooler.

5. Fab up new lines.

6. Fill oil, startup, check for leaks

7. Reinstall undertray, grill and battery.

8. Test drive.


Purchased items:

$66.00 - 1 10AN line kit
$369.00 - 1 oil cooler https://www.summitracing.com/parts/csf-8066

$6.00 - 2in by 1/8in x 4ft Aluminum bar stock

$12.00 - Various M6 x 1.0 screws, lock washers, and lock nuts.

$3.00 - 6 ft of 1/2in foam pipe insulation at Lowes.

$10.00 - Cable cutter from HarborFreight for cutting the SS branded hoses https://www.harborfreight.com/10-in-...ers-63827.html

$6.29 - 2 exhaust hangers https://www.oreillyauto.com/detail/c...exhaust+hanger

 

I removed the undertray which was still a bent up quite a bit. The plastic grill under the bumper. The battery so I could get to the left mount of the oil cooler. These are the old lines and the cooler removed.


Old lines

Upside down pic of old cooler.

 

I fabbed up new mounts by using the aluminum bar stock to create 2 L shaped hard mounts drilled to attach to the new cooler.


New hardmounts on the new cooler.

I then took the exhaust hangers and cut them up to fit on the new mounts and also bolt to the existing 2 bolt locations on the stock radiator. It took some cutting down of the width of the rubber hangers so they both fit side by side and the holes lined up with each end correctly. I had drilled the new hard mounts to accept the bolts with washers and locknuts hold the rubber mounts.


Back side

Top side

Front side

 

I then hung cooler but first I added some of the pipe insulation cut in half and glued to the top of the cooler with 3M spray adhesive (mostly to make mounting easier).

 

Nice!
Do you still have a thermostat in that setup?

 

I now could mount the cooler so I could do the next step of fabbing up the lines. I did not leave the pipe insulation on the bottom of the cooler because once the under tray was reinstalled it was too much bulk. So I replaced it with a thin piece of cork gasket material just to keep the cooler from scraping against the metal undertray and seal up to bottom a bit. The rubber hangers were very easy to mount to the stock locations from above in the engine bay.

 

Next I fabbed up the hoses. The hose kit from Evil Energy had 10ft of hose (way more than needed but for another project I'll need to remake the hoses later this year ). I did the rear hose first. Its very easy to do the AN ends. The key is to use a small screw driver to pry the SS mesh away from the hose end when cut so that the compression fitting can seat all the way on the PTFE inner hose. The old RB hoses were just a bit too short to be reused for this. See pic below.


This shows the old RB hose is not quite long enough to attach to the new cooler connection.

 

I fabbed up the lines. The rear hose used a 90 degree fitting on the engine side and a 45 degree fitting on the cooler side to make an easier connection with less bend needed. The front line is just straight fittings on each end and the hose is long enough that it can make the bend around without kinking.

 

Before I put the undertray back on, I started it up on the lift and ran it until good and warm and watched for leaks. No leaks and I could feel the oil pumping thru the lines as it ran. I also noted that the temp guage stayed at 1/3 without any movement higher. I took my infrared thermometer and pointed it at the oil filter as it was running and it never got over 180F. So I buttoned it all back up by putting the under tray back on (after unbending it some more and repainting it) and took it for a drive. The temp stayed at 1/3 the whole time even in heavy stop n go traffic. I later took it out on a day when it was 100F here and it performed the same. Again I used the infrared thermometer on the oil filter and it still stayed at or below 180F. I'm very pleased with the resulting installation. If you are worried about the lack of a tstat you can get external ones to do that and hook it up on the input side.

 

I think I mentioned it doesn't in the first post.

 

Great write up, thanks for sharing this! Looks like this is a great solution for worn out, missing or badly damaged oil coolers. It's not stated often enough how important oil temperature and cooling are to rotary engines. Nicely done.

 

Thanks!

My main goal was to do this without replacing the radiator (which is not that old but is an OEM replacement ) and maintain the oil cooler position in my SA.

 

Good informative writeup and info, well done. I had a car slip off the jack a couple years ago much as you describe. My mishap took out the oil cooler and radiator, plus the radiator cap went up into the underside of the hood putting a nice little bulge in the skin. All this just after redoing the whole car. Luckily, I had spares of everything and a little PDR brought the hood back.

 

You did a much better job at doing damage. Wow!

 

Everyone has their talents!

 

Ouch!

 

That's a quality-looking oil cooler. I'm running an aftermaket Setrab unit on one of my cars, and it works well.

YMMV, but I have had trouble with swivel AN fittings, even the ones from recognized brands. They're convenient for routing but may eventually leak.

 

I'm keeping an eye on them but so far no issues. I even cleaned up the lower engine pan so I can easily see leaks if they happen.
So this cooler is about 1/2 the price of a Setrab but t is dual pass and easy to mount.

 

Did a GA mountain run right after this in August and no leaks. Cooled fine. So far so good.