brianw

I have an oil leak directly under my top mount oil cooler on my 83'.
does anyone know what it could be? I can see it coming from directly under the cooler. Don't relly want to just start taking stuff off till I find it if someone has an idea of what it could be I would appreciate it.

brianw

how do you repalce those?

nosajwrx-7

not sure, I haven't done it. I would think, remove, replace, reinstall. If you search you will probably find it, or buy a haynes manual.

brianw

just thought maybe someone out there new of the top of their head. Thanks.

slashdawg00110

off the top of my head ... the procedure is vaguely described in the haynes and FSM. Do a search for 'beehive' or 'oil cooler' here and at mazspeed.com. You'll get some tips and gotchas.

Lisa

Just a warning - if that's where your leak is, check your heater hose. It runs underneath the oil cooler, to the firewall. If your oil cooler is leaking, chances are it's dripping onto the hose, which is going to cause it to blow eventually. Trust me, this just happened to me & you DON'T want that. Check your hose, order it NOW (you won't be able to find it in too many places). It's a common failure problem, apparently.

As for fixing the leak, can't help ya there.

rhinor61

I can't believe how many comment on a posting but never really add any value.

Its 2 10mm bolt heads and the also have to remove the metal supply tube with out twisting it, and remove water hoses. Clean up oily mess, remove old o-rings.
Install two new o-rings, and re-stall. Also the banjo washers (crush 1 time).
Good point, replace the factory bent heater hose, oil leaks ruin that rubber hoses under the oil filter.

Personally, I would take this opportunity to install the a air to oil cooler and remove the water to oil cooler under the oil filter.

Its is a know fact that 83-85 12a Rx-7 are prone to dowell pin o-ring failure, I believe it is because the oil is not properly cooled. Some members will argue about this, but even Mazda own racing division says "with any HP mods, back date to the ealier oil cooler system"

I would take a look at your radiator too when/ if you decide to do the upgrade.

Parts needed: 79-82 oil cooler, oil cooler hoses (upper, lower) oil filter pedestal, short style radiator 79-82 and fan shroud if still running clutch fan.
Or you can get a set up from a GSL-SE which put the oil cooler in front of the tall radiator.

erick1120

If I remember right there are 2 10mm nuts on the bottom that have to be removed, you have 2 coolant lines that have to be removed, and the oil line running from it. The nut on the oil line is either 22 or 23mm and you CANNOT get a socket on it. You will have to use a box end or open end wrench. I would also recommend getting new banjo washers for this bolt at the same time as well as the new rubber O-rings. I was able to find all the parts at the local auto parts store. The hardest was finding the banjo washers.

nosajwrx-7

There you go guys, you gave him the fish!

brianw

Okay got all that off.I removed the two 10mm nuts on bottom (attaced to studs on bottom of cooler) but it still feels secure. Is that right or didi I miss something? I don't want to try and knock it lose if I haven't got the right bolts out.

slashdawg00110

There's a third bolt. This thread describes removal.

https://www.rx7club.com/showthread.p...hreadid=198813


And that means I've now posted a value-added comment!

brianw

yes you have but i already found it got it out and am just taking a wrm up break. Thanks though.

slashdawg00110

Excellent. Warmup break? Where are you? it's cold outside? Anyway, glad to hear you got it out. What are you doing for the crush washers?

brianw

I have to finish putting the banjo back on tomorrow but I got some o-rings that fitt and I'm going to try them. I'm in hannibal MO and it's below freezing out here!This sould be the last oil puddler I have to fix. Atleast I hope so, I would really like to be spending my time/money on performance!
To answer my own question. NO it's not an easy fix! really it is but sure is a pian in the ***.

slashdawg00110

where is hannibal, MO. I'm in KC and it's cool but not below freezing. Yet. I know what you mean about working in the cold. As a poor college student, i once changed out a water pump on my 76 VW Dasher in an ice-covered parking lot at about 10 deg F. Brrrrr.

brianw

It's just outside of Quincy IL. It wasn't soo cold but the wind was really blowing. I don't know why but it gets alot colder here than other places that are not too far. It must be the river it's only about a mile from me.

brianw

Man this banjo fitting is a real pain in the ***!Does anyone have a trick to it? I'll try anything at this point, Can't seem to et it to thread.And yea I know ,(when first you don't succeed,try and try again) But maybe if I held my mouth right!

slashdawg00110

I haven't tried that banjo, but I know the ones on the fuel inlets are a bitch. I just keep trying. Sorry.

Rx7carl

Try loosening the front nut on the oil pipe, might give you some wiggle room to get the threads started, or loosen the nuts a bit on the cooler. Its a PITA I know.

Rx7carl

Words to live by! Ive lost 2 engines from this.

brianw

Thanks for the tip Carl. I'm going to my newphew's for his birthday tonite/today,its about 3hr round trip so I'll be back at it tomorrow.

slashdawg00110

How do I know when I need to replace the o-rings? I got a set and had planned to replace them. Went to R&R the hoses this week (oil covered and soft) and found that there was no oil on the underside of the cooler. There's oil all over the side of the engine, but nothing on the underside of the cooler. So I left the cooler alone and just replaced the upper hose and shortened the lower hose by an inch or two and remounted it.

Carl - thanks for telling me not to risk tho soft hoses. The section I cut out of the lower hose was so soft it was scary.

Am I looking at the leak o' death? Am I misunderstanding what the leaky oil cooler shows up as?

brianw

If it's dry under you're cooler I wouldn't worry about them unless you're taking the cooler off anyway in which case I'd definitely replace them. How about the oil pressure sending unit? I noticed it's under there too. Keep looking it has taken me awhile to find all my leaks. There are alot of places for oil to come from.

Rx7carl

Slash, since the o rings are under the cooler, the cooler itself wont be wet. Only the area under it. I'd wash the area good, and start looking for the leak. Like Brian siad, it could be from a number of places. Troubleshoot instead of throwing parts at it. Less frustrating that way. The leak o death usually shows up in the little valley of the rotor housings where it says MAZDA 12A.

slashdawg00110

hell, i got oil everywhere down the side of the engine and even under the car (airflow moving oil?)

not much up on the top of the engine, mostly looks like dirt.

I have some degreaser, so I can clean off the side and check where the leak is coming from.

My oil pressure guage isn't working. Don't know if that's b/c the guage is shot or the sending unit is shot. Not that far yet in troubleshooting.

Trust me, I'm too effing cheap to toss parts/money at anything. Primary evidence is my extremely amateur welding job on the wheel wells.