solaxyfox

I recently got a 1983 RX-7 from someone that was giving it away to a good home. The original reason was hearing a 'boingy boingy' like a rubber-band sound. When I went to pick it up, it started after 3 tries, and idled fine. I drove it away, leaving my daily driver behind.

I had to add a half-gallon of coolant and about a half-quart of oil to top everything up (the coolant light came on after turning the corner of the block... luckily two more blocks and I met a Kragen's) and I took it home with all the warning lights happy, and the engine purring like a chainsaw.

Since then I have noted a few quirks that I need help diagnosing / repairing, as I have until the end of next month to get it smogged (California Car... stupid rat's nest). It leaks oil like a sieve, to the point where I need to add a quart of oil after its been sitting. Oil is splattered underneath the chassis, and attaching itself to the guard of my cat, not to mention the engine block, making the thing smoke if I'm not moving.

Granted, columns of smoke rising out of the wheel wells *looks* damn cool, I'd like it to be a bit more efficient, as I wish to drive this around as a fun car.

My oil pressure gauge reads 30psi at idle, and between 60 and 100psi above 3000RPM, depending on how recently I topped of the oil (30 @ idle is pretty constant, though).

I cleaned the engine of oil and junk with some engine clean, hosed it off, and drove it for a while. I noticed it was leaking oil streight down from the oil / water cooler unit, and also oil had pooled on top of the engine block where it reads 'Mazda 12A', next to the oil filler.

Over the course of having this car, I've replaced the air filter (old one looked /ancient/), oil filter (old one beginning to rust), and fuel filter. For oil I've basically been feeding it pretty much anything at hand that I have spare. Usually 10w30 50/50 Synth blend (had abour 5 qts surplus).

Once I get a shop manual, or a Haynes, I can take the oil cooler assemply off and fix the O-rings on it, as well as replace the badly worn coolant hose that attaches to it.

But I can't afford to get the engine rebuilt, or even the equipment and time to remove the engine to get at the Dowel O-rings that I fear may be the culprit.

To complicate things, I have a month and a $100 budget, with one day a week I have spare to devote to my baby.

So I'm asking any of you RX-7 wizards out there if there is a jury-rig for the dowel o-rings, or perhaps if this is alluding to a serious problem that I should just go Pick-n-Pull a 13BT FI engine and deal with that instead of worrying about the 122,028 mile 13A. If memory serves, a long-block from pick-n-pull is around 500-700 dollars.

I tried looking back 5 pages of threads to find something to aid me, but I havn't found any... if I missed something, simply a link will be great, and I'll read it before asking any (perhaps stupid) followup questions.

kettlman

iTrader: (2)

i'm not too familiar with the 83's oil cooler. if its under the radiator which seems like from your words, there are two hoses that come off and attach to the black. they are easy to fix, the ones on the block are just a couple washers you can get from mazda, like a couple bucks each. and the ones on the cooler itsself just make sure there tight but be carefull not to strip, might want to strap some teflon tape around the threads. the oil filter o-rings are simple too. the o-rings should be a couple bucks also, and all you got is a couple 10mm bolts to take off. and one thing about rotaries..............don't use synthetic oil.................. then after you get the oil leaks under control.. do a seach for MMO. marvel mystery oil. i havn't used it personaly, but there are rotorheads that swear by it. check that out.... and if you have time, i don't know if they are still there, but in concord there was a junkyark called mostly mazdas. i used to get some good stuff out of there. good luck and drive fast.... another thing, try posting in the west section if havn't already.. you might get someone to come over and help you out.

jorx81@aol.com

iTrader: (6)

83 has water cooler oil cooler, like he said.
leak is probably coming oil cooler, check the bottom.
if that's the only oil leak just replace the seals, it's a bitch with the engine in though.
good luck with the emissions.
ask a cali guy on the forum how he passes.

and no synthetics! other's may argue but in the end it just cost more. I'm a castrol 20w-50 guy.

peejay

Yes, that's definitely unusual. Because while *piston* engines go 'boing boing boing', the Mazda engine, by contrast, should be going 'hmmmmmmm'.

solaxyfox

So it might actually be the oil cooler, then? Its kinda wierd it could spray oil all the way to the front of the engine. I seem to recall that the 13A had a dowel o-ring leak if oil was there, from another thread. But if it is just the oil-cooler... I'll pull that thing out and get it all spiffy.

I'm only using synthetic / synthetic blend because I have it lying around, with no other application. My daily driver takes synthetic 5w30, but I have a small stockpile of 10w30 Castrol 50/50. There was also some 20w50 that was in car, which I'll probably end up using when the oil system isn't barfing all over the rest of the car. >.<

I'll pull the cooler out next time I get some serious time with the car. It will be a pain... but at least its *not* a battery on a Dodge Intrepid. Now *that* is a pain! (Just got back from work, heh... guess what took two hours to do...)

Hopefully I can get my baby up and running by next month, then.

Anyone know if there's a thread for most oft /coolant/ leaks? I manage to squirt coolant in much less quantities as well. It appears to be coming from the left front quarter of the engine. I already replaced the radiator hoses and got new clamps.

I'm trying to not ask for stuff that's already been answered... but having spent so much time working on today's fuel injected bits of crud, having not only a rotary, but also a carborater, is kind of daunting.

Also... I think the 'Boingy Boingy' sound was the water pump deciding to try and pump air. There was no coolant in it that I could see when I first got it, and the reserve tank keeps drying out as it happily eats the stuff. It is still a disturbing thought that I don't actually have a real clue on what it could be, though.

Once I get her past smog, I'll be trying some of the Nikki Carb ideas I've been reading about. Probably link up the secondaries, find a way to set up an easy bolt-on change from being smog-legal to not... we'll see. I should probably get rid of the rust on the exterior and restore the inside before I get serious into performance, though... anyone know a good place to get the rugs for an '83?

I'll try to get some pictures of it next time I'm up where its stashed. Unfortunately I live in an apartment, so I have it stashed in my parents garage :P Someday, I hope to have a RX-7 that will impress the masses by her very presense! ... And if its fast, too, more power to her!

hanman

I am not familiar with the Oil coolers on the 81-83's, most of the guys replace them with the oil/air coolers that mount under the radiator. I would try and fix that leak first. See if that solves the oil on top of the engine. Otherwise it is probably the "leak of death". No cure except a rebuild. Good news is that you can probably drive it for a long time that way, it will just leak oil. Sooner or later it will give up the ghost, so in the meantime save your money for a rebuild.

Also, DON'T use synthetic. It is most likely increasing your leaking problems. Plus, there is a long standing controversy over using syn in rotaries. Bottom line... Mazda recommends NOT using syn in rotaries. MY opinion: Why pay extra for oil that may actually harm your engine?
Coolant leak is most probably your water pump. When they go bad they leak out of the weep hole in the bottom of the pump. It is hard to find that leak. It will be on the ground on the left side of the engine as you face the engine.
Oil pressure is fine, that is how they run normally.
By the way, your engine is a 12A, not a 13A or B. There is no 13A that I know of.
Dont' even think about switching to a 13B fuel injected unless you have time and money. Which it sounds like you are short on. If you want to replace the engine, find another 12A. They are common.

jorx81@aol.com

iTrader: (6)

if you have the "bee hive" water/oil cooler it will be much tougher than an intrepid battery install, they are a pain but you don't have to remove the wheel like a sebring or stratus.
either way 30 minutes with the right tools.
I've only replaced the o-rings(4 between cooler and pedastal) only once with engine in car, it's a pain.
gear wrenches make it easier, definetly need u-joints.
check the bottom side of the cooler for oil to be sure.
You may want to remove oil pressure sending unit and re-install with teflon tape or loc-tite.

It's my understanding that 83's all came with "bee hive" water/oil cooler, am I wrong?

peejay

You're right.

'83 was a transitional year. It was a Series 2, but it had some Series 3 parts, like the different driveshaft flange bolt pattern/non-replaceable U-joints, and the beehive oil cooler.

And then there's the '83 LE, which was the only 12A car to come with 14" wheels...

slashdawg00110

It sounds a lot like the oil spray pattern I had when I had leaky o-rings on the beehive oil cooler in my 83 GSL. They were a royal PITA to replace. You should also replace the coolant hoses that feed the cooler. They're no doubt oil-soaked and ready to fail if they aren't already leaking.

rx-7ames

iTrader: (1)

just to touch on the synthetic oil subject, i was told not to use it by the lead mechanic at the mazda dealership in town. as we all know, the rotory engine has an oil meetering pump that pumps oil to the carb and mixes it with the gas. synthetic will not burn, so if you mix non-burnable oil with the gass, then it isn't doing it's job. makes since to me. that is how the mazda mechanic explained it to me.

solaxyfox

Well, I started taking her apart today. I made it as far as getting the coolant hose off, and getting a new one ordered. It was swelling, coated in goo, and flared past the clamps. Very bad condition.

I also discovered I could not for the life of me figure out on how to proceed. So the repair manual was added to my list of things to get tomarrow.

As far as oil goes... there is a huge thread on it that I read through from the RX-7 FAQ thread... synthetic oil does in fact burn like regular oil, its more consistant, yadda yadda.

I already decided what I'm going to put into her when she's running, but when she's eating a quart / quart and a half just to fire her up weekly, I'm going to throw in whatever I happen to have availible that is on the 'marginally ok' list. I won't be pushing her, and chances are, it won't even stay in past an hour, anyway (how long she runs to warm up before going back to the garage).

I've noted an odd splatter pattern of 10w30 Castol from under the engine clear half-way down the exhaust guard. Brand new stuff.

This is also why she smokes so damn much, because the oil gets on the cat guard, on the engine block, splatters the exhaust...

If this fix will get rid of the massive oil leakage, then I'll start worrying about feeding her the 20w50 I plan to use for the upcoming hot summer...

Mainly, I gotta pass smog in a month's time. If I can do that, I'm set. Still trying to find a good thread to hop into on the Western States Forums, though.

Incidently, I was eyeing the conversion someone said about using the electric air-pump from the FD to replace the belt-driven one. And I've also been staring at the Sterling Modded Carb...

But those require money, so it will come later. Much later. Assuming the dowel o-rings are okay. That'll be my next big concern.

I'll update what happens tomarrow when I next check the threads ^.^ See if the o-rings will fix 'er up.

solaxyfox

Alright... now I'm stumped. Haynes in hand, my half-complete set of wrenches and a pile of small sockets, and I'm all set to go at the oil cooler...

... except the Haynes doesn't mention the beehive oil cooler. Only the one under the radiator... sooo...

Improvise, right. There are three 14mm Nuts with washers that are of the 'hold something on' type. Two of these have been removed, with only the one near the firewall left.

But there's also a suspicious 7/8" bolt that's under the cooler, conveniently where none of my appropiate sized tools can fit.

Do I just need to get rid of the 14mm Nuts to pry it off... or are there more things? Once more, halted by my lack of knowledge.

MosesX605

I've found the Haynes manual to be great for '79 model year cars, not so much for the later models. The supplimental chapter towards the end of the book is not nearly enough to cover all the changes in the 12A powered cars, let alone the 13B powered SE models.

Anyhow I have an '83 manual sitting around the apartment and took some shoddy pictures with my webcam of the blurb about the oil cooler. Hopefully it will help you out...

jorx81@aol.com

iTrader: (6)

i've used u-joint from underneath the car, don't give up it's possible.

solaxyfox

Well, on the positive side I now know that I have loosened the bolts that shall never be loosened!

I still have nooo idea what bolts I'm looking for, although those pictures from the repair book helped a LOT. My haynes just doesn't cover beehive coolers.

Maybe they're trying to forget about them, in order to passively make all RX-7s get a better system...

I'm going to take a stab in the dark tomarrow with my trusty wrench and ratchet set, and hope my joints are flexible enough to make up for not having a U-Joint availible at the moment... should I get the darned things /off/ I'm getting a brand, shiny new toolset in celebration, though...

There should be a little blurb on this silly cooling system somewhere... does anyone know a thread on how to adapt to a newer model oil-cooling system? Perhaps off of a FC?

My poor 7 is on jackstands until I fix 'er... and she deserves to be out on the road, because I keep seeing RX-7s all over the place now :P

solaxyfox

Alright... just as a question for you people out there that know about this oil-cooler system...

Is the oil inlet bolt right-handed (standard) or left-handed thread? Also... what friggen size is it? Its an inbetween size according to my wrenches...

Last thing to remove before I get the unit off. Nothing quite like laying underneath a 12A with coolant dripping on your forehead to really give you a sense of actually fixing a car :P

Rx7carl

They are all right hand threads. Its an odd size on the banjo bolt. I think Ive used a crescent, or an inch size wrench in the past. Oh and on the NEVER LOOSEN bolts. No biggie. Just get 4 of those o-rings and replace them all.

solaxyfox

Alright! Well, thanks to all of your help, most notably the pictures that saved my sanity, and the final note on the banjo bolt... I got it off! The oil cooler is now resting under the car, and I'm hoping I didn't drink any coolant by accident, because that would be bad.

Anyway, I ended up having to use my shorter crescent, because I forgot my co-workers crescent in the shop when I closed (D'oh! He's gonna kill me for that...)

Since I didn't have enough leverage, and I couldn't get anything on there, my dad mentioned tapping it with a hammer. I went a step further, slipped a claw hammer's clawed end into the little hole at the end of the crescent, and heaved. The banjo broke free, the RX-7 spat coolant at my face, and I got it all off!

Instead of a week, I could probably do it in an afternoon...

And I'm going to assume, since my O-ring went from rubber doughnuts to flat plastic washers, that it was my primary oil leak, soon to be fixed within the week (yay!).

MosesX605

Sounds like you're on your way.

Good luck with the reinstall.

solaxyfox

Wow, been a while since I touched this thread. Hee. Well, as it stands I have everything re-installed, and she runs a lot better. Oil pressure comes up faster, drops slower, and oil leaking is down to a small splotch instead of a puddle. (Only 1/4 qt total loss after 24 miles of hard driving)

Still leaking, though. Next thing is the engine steamclean and the oil-pan gasket replacement - but that's probably for a different thread.

I took a few (very few! x.x) hi-res pictures of the area in the car, as well as the oil cooler assembly, and am in the progress of writing a how-to to help anyone else that has to do this rather obnoxious task.

I'll put it up here in its first draft when I'm done writing it, then move a finished copy to its own thread. Hopefully all my bungling will help others!

solaxyfox

Oh, and as a further problem with my baby... recently the starter stuck in the 'on' position while the engage plunger ceased to work. So I'll be replacing the starter / solonoid pack next as well. Then I have to get an estimate for the fender and get the rust bits taken care of...