12A Beehive Oil Cooler leaking oil externally
 

Most of the threads and posts I have seen regarding the words "leaking" and "beehive" have to do with the common problem of oil making its way into the coolant. Luckily, I don't have such an issue, and my oil cooler seems to work properly.

I've been under my car before and seen plenty of oil on the oil pan, I've assumed its because the prior owner used gasketmaker instead of a real gasket. But I looked closer and I realized the source of the oil leak must be much higher up. It does seem like oil is leaking outside the oil cooler. From about 1/3 of the way down the fins, there is always a film of oil, and there is oil on virtually every part below the oil cooler on that side of the engine. The top of the oil cooler is dry so I know the leak isn't coming from my oil filter.

As I understand it, there is an o-ring at the bottom of the beehive that can leak oil out, but then how would the oil be on the fins above it? I also read something about leaking from the "banjo" bolt, but I don't know where that is. Does it sound like I need a replacement beehive? I'm not interested in going to a front-mounted air to oil cooler.

No, all you need are four o-rings. There are two between the finned part and the pedestal. Then there are two between the pedestal and the engine. The banjo bolt never leaks because it should never be disturbed. And even then it has a set of copper crush washers, but there is no need to take it off when pulling the beehive for o-ring replacement. Instead you must remove the flare nut down at front cover fitting (23mm and a 21mm wrench are recommended to hold the front cover fitting from turning as you loosen the flare nut). Then there are two 10mm nuts under the rear iron which anchor the beehive to the engine. Lastly there is one 12mm bolt with a lock washer and flat washer at the far end of the pedestal in the top inspection cover area. You also have two coolant hoses that need to be disconnected but they are pretty self-explanatory.

If what I just said isn't making sense to you, I don't know how to explain it any clearer. I just did a beehive o-ring job a couple weeks ago so it's pretty fresh in my mind still.

You also might need to grind the inner wrench down, or get a skinny one if you can. If I remember correctly, I had to grind one of the wenches down. Down try without using two wrenches, you will most likely kink the tube.

Jeff20B thank you for your input.

If the leak is coming from the o-rings, and all 4 o-rings are BELOW the finned part, then how come I have oil all over the outside of the finned part? it seems to me like the leak is from within the fins, not below them. Oil does not appear to be leaking out from around the filter, which is above the fins, and if it was leaking from below the fins, how is it making its way up the fins against gravity?

I purchased a used beehive off ebay because it wasn't much money, so I figure I can replace both the o-rings and the beehive and see what happens.

I'm sure your ability to explain is stellar, and my ability to understand is lacking. Can I just clarify, will the procedure you described allow me to separate the beehive from the pedestal? or is it separating the beehive & pedestal from the block? Or is it doing both? The only reason I don't grab my wrenches and go at it is I know there is stuff you're not supposed to touch. I don't even know where this "banjo" bolt is located or what it holds together. Do I need to worry about that when detaching the beehive from the pedestal? Do I need to detach the pedestal from the block if there aren't any leaks between the pedestal and block?

Let me put it another way. Suppose my Mazda took disruptor fire from a firefight I had with some Romulans in my driveway. One of the disruptor bolts hit my oil filter, vaporizing it and the upper half of my beehive oil cooler, mercifully missing my rotor housings. What do I need to do to remove that half-vaporized, broken, useless oil cooler to attach the fully intact, complete one I bought off ebay without the pedestal?

It's like Jeff says, your O rings are toast.

You gotta unhook the hoses, remove two 10 mm nuts underneath and a 12 mm nut or bolt (don't recall exactly) from the top.

Then loosen that big old banjo bolt.

That's what KC is talking about, you don't want to kink that banjo bolt. Make sure your wrenches are up to the job.

And I got spare bee hives if you run into trouble.

Don't take the banjo bolt off. I've never had to. I just loosen the nut down on the front cover leaving the banjo bolt and its copper crush washers intact. Is this not the correct way?

Jeff, I don't see an issue in doing that. I think a lot of guys remove the beehive to clean it and separate it and replace the two o-rings on the bench and then the other two on the mating surface on install. I've personally always removed the rear banjo bolt and bought new crush washers when installing new o-rings on a beehive. .