Rob.W

I recentlu purchased an 85 RX7 for the princely sum of $275, the problems being it needed a fuel pump. OK, I put in the fuel pump. It started, ran, and kind of drove. Almost immediately I realized it needed a clutch slave (the lovely pedal fell to the floor, at least it wasn't the throw-out bearing).

Now, my poor little Rex is sucking down enourmous ammounts of coolant and ejecting it right out the exhaust. I suspect the entire cooling system is bad, however I know the tstat is bad as well as a couple of the hoses.

Now, it's gotten very close to OHting twice. It got to the point where I thought it was too close, shut it off and pushed it off the road.

I would let it cool down, open the radiator cap, and it would be damn near empty, with the reservoir full. The radiator cap is new, as well. So there should be pressure in the system (AFAIK). But that's not what I'm concerned about, I'm replacing the entire cooling system. Any suggestions on what to use for radiators and such? Anything a bit beefier than stock that doesn't need a shoehorn? I digress though...

What I'm really looking for help on is thus: Do I need to rebuild that engine now? For a good minute at startup it will spit out a literal cloud of white, sweet smelling smoke (a cookie to whoever knows where THAT's coming from...). Also, it will actually lose so much at startup you can see the cooland coming out of the exhaust and sticking on the ground, even forming puddles! However, as soon as the seals warm up, bam, it doesn't do it anymore.

Should I replace the radiator, hoses, etc. before I decide to pull the engine?

If I do have to pull the engine, my transmission seems to slip. Going into gear it sometimes lurches forward before it "slips" into gear. In second, it always grinds (well, not grinds, but has difficulty, I'm sure if the tranny was of lesser quality it WOULD grind, though), and tries to slip out of third. I have a spare transmission, I'm assuming yes but would it be a good idea to replace that at the same time?

Thank you in advance for your time, I'm hoping beyond hope it doesn't need to be rebuilt, but if it does, I'll suck it up, get the rebuild kit and get down to it.

OH, sorry, one more thing. In a couple of cars of mine I've been stranded, with the tstat being the issue. Right there on the road I've pulled the tstat, smacked the crap out of it to get the middle out, put it back in and drove on my merry way. This won't harm anything AFAIK, however it's better to aks. Would it be beneficial to have a superficial tstat? It would basically flow coolant all the time, so I don't see the problem, however since I am not a rotor head (my first Rex), I thought it would be better to ask.

BlastinSideways12A

Chances are that you need to rebuild. Running without a thermostat is BAD IMO. Your oil temps will be reasonable and your coolant temps low. The housings will get warped.

Alex-7

You need a rebuild. You can replace the radiator and hoses, even the t-stat and it won't behave any differently than it does now.

Bad seals, bad clutch ect. Your car needs a complete "going through"


You came to the right place, good luck.

cpa7man

iTrader: (2)

Alex is right. You want to always run a thermostat. In a racing app you might drill some holes in it but unless it's the 95 out you need it.

Rebuild it now, before you don't have anything left to rebuild. Alternativly look in the for sale section for a good used motor.

Rx7carl

Welcome to the forum, sorry your first post brings bad news, but theyre right. Maybe put a real location in your profile? We got 1st gen people all over.

Rob.W

Wow, I'm amazed with the response in an hour or two.

I'm definately sticking around here a while.

I suppose I'll go pick up the rebuild kit today and start taking it apart... *sigh*

Needless to say, I don't trust the radiator though, either. What kind of radiators and fans bolt in there? J/W, I suppose if I have to I'll get a stock replacement, but I'd really rather not, since everything I've heard about these little guys is they're great unless they get too warm, and I don't want that happening again.

Thanks a lot guys, I really, really wasn't expecting this kind of response already.

aussiesmg

iTrader: (1)

Go for the three core replacement, you may have to have it done by a radiator specialist but its a big improvement over stock 2 core.

Hint: if you're doing the rebuild yourself at least consider some porting to improve flow and power, templates are available so you can DIY.

Also do some research as to what power etc you do want, what emmisions you need if any, etc at this time as it makes sence to upgrade the parts while the motor is out.

Rx7carl

Before you run out and buy anything, read up over on the faq thread and archive and learn what to expect during a rebuild.

A good stock repleacement rad will be fine. Some people here like the www.radiator.com place. Also look in the FAQ thread and archive about eletric fans.

Well your in pullyap. Isint TJ from there? Or was that Iotus? Anyway, your not far from pineapple racing I think. They are a reputable builder. Atkins is up that way too but not sure how far.

Rob.W

Atkins is right down the street on Meridian.

No emission equipment required, up until a couple weeks ago I worked at emission control and know everybody there, passing will not be an issue.

Since odds are I'm going to pull the engine I'll at least do a port job on her.

Performance the 12A is fine for me, for right now. About how much out of pocket cost can I expect for the clutch, radiator, engine and etc.? I'm guessing with the rebuild kit around a grand, probably 2 to 2500 if I get a rebuilt engine.

As for the TStat thing, I don't mean removing it. I mean taking it out, beating the crap out of it (= getting the center out), and putting it back in. That means it will flow full coolant all the time.

Alex-7

"gutting" the thermostat is not worth while. Why don't you just get a new one. They're cheap from the dealer.

soft and hard seal kits for a rebuild will run you anywhere from $400-$700. I'd recomend Atkins or rotary aviation for this stuff...... They both sell a video to walk you through the rebuild as well.

A nice new clutch setup like a centerforce for example will cost you around $300. There are much cheaper alternatives, but it's always nice to have a good clutch.


If I remember right I paid $120 for my stock replacement Modine radiator.

Rob.W

I was wondering for an increae in flow. *shrug*

It's not really a bother, you just beat the crap out of them and it usually falls out. Yeah, I'll just put a new one in there.

bliffle

Before you rebuild, which is a fair amount of work, cleanup your cooling system. Start with a new OEM Tstat and Rad cap from Mazdatrix (about $30 total). While you're at mazdatrix.com get the crooked heater hose that goes under the oil cooler ($40, it's also possible to get a length of autostore 5/8 hose in there, I've done it, but it isn't fun). If you need to replace the rad go to radiators.com ($125 delivered in 3 days). When you replace the heater hose coming out of the junction near the bottom of the raqd on the passenger side insert a tee with cap from the plastic $6 prestone flush kit available at any autostore. All of this work can be done in a couple hours. You can use rad hoses from the autostore, but not rad caps or tstats: go OEM. You don't need an expensive radiator (I have two of those generic rads working in my DDs for the last couple years) nor do you need a special fan. For comparison, I had the rad on my 74REPU re-soldered for $125 and it seems good as new.

Probably the white smoke at startup is caused by the infamous Internal Water Seal Leak which is caused by a history of overheating, which was probably caused by that heater hose under the oil beehive letting go suddenly because it's rotted from oil leakage and dumping all the coolant on the pavement VERY quickly: you can't make it home and it's a bear to replace that heater hose by the side of the road so do it at home before it happens! That's probably what happened to the previous owner and that's why you got it so cheap, tho I've gotten them for *free* in that condition.

Sometimes people solve the problem by removing the intake manifold and replacing the ORings there, but there are other internal seals that may also be fried by overheating, so I go right to the Temporary Fix which we've developed which is cheap, easy, and takes about one day of light work (you spend most of your time waiting for the engine to heatup or cooldown while you drink beer or go swimming). I've got the process on my Palm Pilot but you can find it by doing a search. If needbe you can lookup my entire first experience with this "Temp Fix" about 2 years ago under my name with "Prestone" in the title. That Prestone plastic Tee will save you a lot of time and trouble, especially since you can do your flushing by connecting the anti-siphon to the garden hose and reverse flush with a bubbling brook coming out of the rad top (not a spray please!).

Basically, the temp fix (which has been running two years in my 83) consists of thorouhgly cleaning the cooling system of crap, especially oil, and applying "Colloidally suspended copper or aluminum" in a specific way to ensure that it seeks the tiny leaks and then gets cured securely in place. That colloidal stuff is sold in autostores and is easy to identify as a clear plastic bottle with clear liquid with shiny copper or al particles settled at the bottom. I use the copper stuff.

When you finish testing the temp fix for a couple days be sure to add some coolant because otherwise corrosion will start quickly.

Rob.W

You spoke of stumble, wow, pretty much my car to a T. Horrible white smoke on cold startup and it refuses to idle below 3 grand (no rat tails nest, no idea how well genius there did any of the repairs, if it's any inclination though it has a huge spoiler that just looks ugly, underlighting, and it used to have a supertach... he was a ricer. , and is sluggish without full throttle or above 4k RPM.

So basically you just flush the radiator a bunch to get the crap out, put in CRC, let it sit, (drive it a bit?) drain, and repeat until white smoke stops and it holds pressure?

Kentetsu

Well, good new is that your clutch may be ok. The lurch into 1st, grinding a bit into 2nd, sounds like low clutch pressure (clutch not disengaging completely). You may have air in your clutch lines since the slave replacement. Too bad about the motor though...

Rob.W

That's possible, I thought I bled it completely but I may not have.

I'm oging to try the quickfix before I pull anything off, though.

bliffle

It's a bear to bleed that clutch hydraulic system properly. That's probably where your problem is. The easy fix is to get a $50 power bleeder from the autostore, next best is a $10 Speed Bleeder (available on internet, sometimes at autostore). One guy here used an old bicycle tube!

Rob.W

Alright, I've got some KW, 2 gallons of Prime 50/50 when I'm done flushing, a power bleeder for that stupid clutch, and a lot of stubborn tenacity to make that motor work. Oh, and a thermostat.

As soon as it's sunshine out, I attack!

Oh, if after this, it doesn't work, I wonder in WA where the best place is to get a motor... step above junkyard, step below full blown rebuild (AKA Atkins)? If anybody has any ideas where to shop for econo rotaries here in WA please let me know, juuuuust in case.

sgieldon

Hey Rob;
Just a Suggestion!
Atkins Motors has a Great Reputation in the Rotary World.
Why not drive to him and have them do a complete Physical.
Your lookin @ 1hr Labor that includes Compression Check. Radiator and Cooling Pressure Test and other stuff.

A co-worker of mine that lives in Bellevue did this with his 83GSL and was going through Some of the problems that you are experiencing.
For a mere $75.00 that Atkins charged him to do all the test he saved about 3wks in time and a **** load of money in the long run.

Point I'm trying to make is (Unless you have some idea of whats going on with your $275.00 investment you maybe chasing your CheckBook just to keep up)!
There will always be one of us on this board to help you. But from reading these Post's and you living so close to Atkins, maybe it might be worth the time and drive to get an idea what direction to start with.
If your a good (I don't know whats going on) and they are minor fixes that no Gauges have to be hooked up to your Car. You might get out of there shop for free. Altough I doupt it from what I've read so far.
Hence $75.00-$100.00 alot easier than $2500-3500 to except.
Good Luck and Welcome.
sgieldon
steve

Rob.W

Right now I'm on a severe budget until my next job starts giving me money to pay bills, so I'm stuck with me myself and I. If attempting to seal the apex seals don't work then I'll worry about shops.