I'm having a very hard time installing a second-gen oil-cooler in my -SE. I procured some 1"7/8 muffler clamps and angle iron and began to build the mount but quickly realized I'm going to have a clearance issue. Not specifically with the cooler itself, but the 18mm to AN fitting on the side.

For test-fitting purposes, I installed a 90degree 18mm to 10AN swivel hose-end in the side-outlet of the cooler. When I went to put it on the car I noticed the fitting directly interfered with the tension-rod mount. I've been shuffling the thing around all night trying to find a spot that would get the face of the cooler above the lip of the lower-apron without impacting the mount with no luck. The only thing that seemed to work at all was tilting the cooler... Basically incling the top of the cooler to bring the side fitting away from the tension-rod mount, and routing the oil-line straight-up through the radiator shroud.

I can't mount the cooler any higher than 1/2" below the stock cooler location without interfering with my intercooler. Its a problem no doubt.

All ranting aside, I'll get down to my question...

I noticed on the bottom of the TII cooler there appears to be a drain-fitting. I didn't notice it until 5-minutes before I packed it in for the night and have been thinking about it ever since...

So, would it be kosher to put the drain-plug in the side outlet, and use the drain fitting for my return oil line?

 

Can't do that. What appears to be a drain plug is the access plug for the thermostat. Yes, the oil cooler has a thermostat just like the coolant system and performs the same function.

 

Do you know at what temperature it operates? Looks like there are a few choices for inline oil thermostats available.

 

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/oil-cooler-thermostat-649437/

Seems like it won't do much harm to remove it. I can give the motor ample time to warm-up, and I don't drive it in cold weather at all.

 

what was wrong with your SE oil cooler?

 

I ran a dual OC's before. I used the stock under rad plus SE oil coolers running in series. I modified the t-stat so it will be completely open or so it wont go in the by-pass mode. It kept the oil cool at the time particularly on a stop and go traffic. The bad is if one gets clogged, then teh entire system dies.

Find a RX-2 oil cooler. It has an external t-stat. I have one and thats the route Im taking with my turbo set-up.

 

It leaks like a siv, and the stock -SE mounts are falling apart. I had the bungs rewelded last time, and it still leaked... I'm sick of cleaning up oil.

I don't think I'll have any luck finding any RX2 stuff locally, otherwise I'd give it a shot.

I just spoke with Chris Ludwig of Ludwig Motorsports. He advised me to remove the thermostat if I want, and simply don't ream on it until the oil is up to temp.

He removed the thermo from his ITS car. Quote: "Just one more thing to fail".

Thanks for all your help, guys.

 

I'm going to Parker Smith tommorow to see if I can find an AN adapter that is the correct size. I don't suppose anyone knows offhand what size the thernostat is?

 

Problem solved. I figured I'd go ahead and post the details for anyone else who might try this.

The thermostat plug for the 2nd gen oil cooler is a 22mm x 1.5 thread. Summit and Jegs do not carry an AN adapter in this size. However, the Parker Store does:

http://www.parker.com/ead/cm1.asp?cmid=683

Part number: PKR 10M22C80MXS MALE ELBOW

This is a 22mm x 1.5 to -10an, 90 degree elbow. They also sell a straight adapter in the same size. They probably also offer an -8AN adapter if you're using smaller lines. The cost for this part was a bit over the top... $38.86 before tax.

Bear in mind, to use this setup you have to remove the oil thermostat completely and purchase an 18mm x 1.5 hex-head plug for the side outlet.

Once I finish the install, I'll post some pictures. Granted it's expensive, will require longer warmup times, and is a bit of a hack... But if you really can't find the room for the TII oil-cooler any other way, this will work.

 

What's a siv?

I made new mounts for mine after the shop that "safetied" my car for this province put the oil cooler on with a zap strap on one side and chewed the one good mount by cramming it in.

 

Sorry... Sieve.

I found that drilling two small holes through the rubber and screwing in some wood-screws worked for a while... I really wish my -SE cooler didn't leak.

 

My friend is stripping another old school RX. I will check just in case.

 

The $40 fitting. Had to plug the bypass with a bolt, lock-washer, lock-nut, and loctite.

 

wowsers better hope you don't bottom out on that, t'would be a shame.

 

How much clearence do you have ?

 

Believe it or not, it actually sits above the lower apron. No worries, the bottom of the radiator is lower.

 

I would just worry about rocks kicked up on the freeway. Too bad you couldn't mount it horizontally, then have an air dam redirect the air upward into it...

 

The mounting position is pretty much exactly the same as the stock -SE cooler, hence the extra effort and expense.

I seriously considered building a horizontal mount for it but I really don't have the room. I have a very tall aftermarket radiator, and instead of inclining it forward as most do I opted to retain the vertical placement in order to fit an intercooler inside the shroud. The radiator is so tall that it extends signifigantly below the frame-rails, making the horizontal mount impossible.





Pic from the last build with the S4 motor. The small fitting between the inlet and outlet is approximatly where the stock radiator ended. Notice where the frame-rail is in relation to the bottom of the radiator... That's where the horizonal mount is supposed to go!

Look at the lower oil cooler fitting pic from my post above, imagine the bottom of the radiator sitting at that level. I have to watch out for obsticles, but the car never had a cooling problem.

I am going to have a little better "ducting" this time tho, in the form of an SA22 IMSA lip...



Hate to trot out this old pic, but it shows the lip very well. It's got a large center duct that is much more effective at getting air to my various coolers.

 

Here's a better pic of the IMSA lip. Funny thing is I was at the meet where that pic was taken, saw that car and decided instantly that I wanted one for my car.