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joshx99
joshx99 New Reader
10/23/08 6:46 p.m.

overheat? This sucks balls. I just had a massive crack open in my radiator and had to drive home anyway. Let's guess what kind of damage is done. I had to drive a few miles with basically no coolant, temp gauge pegged out.

Osterkraut
Osterkraut Reader
10/23/08 6:51 p.m.

Sorry, friend.

If you HAVEN'T popped it, buy a lotto ticket, as you're a lucky, lucky bastard.

joshx99
joshx99 New Reader
10/23/08 6:55 p.m.

Well, it did start after I let it cool and filled it with some water.

Osterkraut
Osterkraut Reader
10/23/08 6:57 p.m.

Oh, a 12A with a blown coolant seal will run fine for a surprising amount of time. If you begin to notice coolant consumption and white smoke out the exhaust, you're in trouble. Some say if you pull the rad cap and see bubbles, that's a sign too.

P71
P71 GRM+ Memberand Reader
10/23/08 6:58 p.m.

I dunno? Mine has 232,xxx miles and got over 60 autocross runs on it this year plus 30 dragstrip passes. It was never overheated as far as I know (bought it from the original owner) but I do know it's never been rebuilt and it has gotten warm a few times (racing). 12A N/A's are remarkably hardy, you might have gotten away with it.

joshx99
joshx99 New Reader
10/23/08 7:01 p.m.

Yeah, I haven't had any issues with the car burning coolant, just with it loosing a lot of coolant all at once, lol. I guess I'll find out tomorrow, I was just wondering what everyone else thought. I guess I was just wondering how long it would run if I did blow a seal.

joshx99
joshx99 New Reader
10/23/08 7:01 p.m.

I'm thinking positive. I believe that putting a new radiator in will fix all the car's issues.

jrtech
jrtech New Reader
10/23/08 7:33 p.m.

Air-cooled Wankels?! That's Grassroots!

joshx99
joshx99 New Reader
10/23/08 7:45 p.m.

Hey, I was stuck on a bridge, I didn't have much choice.

noisycricket
noisycricket Reader
10/23/08 8:47 p.m.

I think I went seven or eight times on one of mine. I went a long time with the oil cooler leak because I was nervous about pulling the cooler off and cracking the big steel pipe, so the heater hoses blew apart with disturbing regularity. I had cut off the bottom of the hose and spliced in a standard 90deg piece so that it was easy to change. Eventually I fixed the leaky O-rings, and cracked the steel pipe, and replaced that too. Rite of passage if you have a late 12A.

My current rotary, with FC housings that crack if you look at them funny, regularly sees 230+ temps while racing. Scares the bejeezus out of me but it's still running okay. When I built it, I only torqued it to 23 ft-lb instead of 29 like spec is, or 35 or even 45ft-lb like some of the big name shop guys say is good. More torque just makes it less tolerant of overheating, maybe high boost drag motors like more torque but temp abuse tolerance is more important to me.

ChrisTaylor
ChrisTaylor New Reader
10/23/08 10:56 p.m.

I had a thermostat stick closed on one of the Spec7's (the one in my av, actually). Ran the remaining 4 hours of the enduro without a hiccup, along with a couple more sprint races before the 2 bolts (out of 6 for those that have seen behind the front cover) of the front bearing "cover" backed out and got taken out by the counter weight, breaking 4 of the apex seals and trashing all 4 bearings in the engine (the rotor faces didn't like the iron seals, either).

I can't complain, it was built by somebody that was supposedly an expert some 10 years ago, has never seen the street, and I only paid $200 for it -- it was my "backup" motor anyway.

At any rate, white smoke and sweet smell are good signs the seal is bad. You'll also see water on the plugs if that's the case. If it leaks the other way, the radiator will overflow from the cap when cold and aerate the water.

noisycricket
noisycricket Reader
10/24/08 9:25 p.m.

Crap, after i posted that, my engine started showing signs of bypassing water. Temp kinda runs a little high at first, then settles down to normal, especially after shutoff.

Well, I'd been planning on pulling it apart this winter anyway.

dean1484
dean1484 GRM+ Memberand HalfDork
10/24/08 9:51 p.m.

There is the old block weld trick for these. I have seen several of these "temporary" fixs go for many years. I did it to my 86 on motor #2. It lasted 2 years. By motor #4 I could do a complete motor swap in under 4 hours.

noisycricket
noisycricket Reader
10/24/08 9:59 p.m.

I think the last one I did went from driving into the shop, to having the next engine bolted to the trans, in 90 minutes.

The only problem with blockweld is that in SOME cases you can FUBAR your rotors by gumming up the side seal grooves. All is usually not lost if the engine otherwise runs okay, it doesn't cost much to just redo the soft seals.

sergio
sergio New Reader
10/25/08 3:18 p.m.

If water does start entering the combustion chambers, you'll know it cause it will be hard to start and then run rough for a few seconds til it clears the water off the plugs. When you park the car for overnight or at work crack open the radiator cap to relieve the pressure so the water isn't forced in by the pressure. I ran my rotary RX-2 with warpped rotor housings for a few months before replacing them. Spraying starting fluid in the carb helps make it start quicker so the starter doesn't burn up for so much cranking.

aussiesmg
aussiesmg HalfDork
10/25/08 4:27 p.m.

12a engine are extremely reliable but do NOT like to overheat at all, be very afraid.....

On a side note replace the coolant hoses below the beehive cooler as a matter of course upon purchasing any 12a, and best bet is to replace the beehive and use a factory FMOC from an early 1st gen or a 2nd gen, as the beehive O rings will leak and the oil will leak onto the coolant hoses which in turn have a reputation for instant failure at the most inopportune time.

joshx99
joshx99 New Reader
10/27/08 5:35 p.m.

I haven't driven the car yet, but it starts just fine and holds a perfect idle still. It did want to die when I revved it at first, but I think that's more due to me not driving it for awhile.

jstein77
jstein77 HalfDork
10/27/08 7:10 p.m.

The chances are very high that you've warped the rotor housings, which will eventually lead to coolant loss and an ever increasing spiral of overheat, warp some more, overheat, ad infinitum.

joshx99
joshx99 New Reader
10/27/08 9:22 p.m.

You're not helping to channel positive thoughts to the rotary gods here, pal.

jrtech
jrtech New Reader
10/27/08 11:07 p.m.

Time to get you some V8 'Merican Horsespowa!

TheBen
TheBen New Reader
10/27/08 11:15 p.m.

Be smart, swap in some 1915 Franklin steam power!

Jensenman
Jensenman SuperDork
10/28/08 1:11 p.m.

Lucky for me, I've never had to test the 'how many times can it overheat' thing. I'm going to say if it starts and runs good and doesn't immediately pressurize the cooling system on a cold start, it's going to be OK.

By pressurize, I mean with a tester on a cold motor, it shouldn't jump more than 2-3 psi in the first couple of minutes of running from ice cold. OTOH, if the cooling system pressure is up to, say, 10 PSI within 90 seconds I'd be concerned.

BTW, the 'temp gauge pegged' thing is actually a fairly good sign. Here's why: the temp sender 'bulb' has to be immersed in coolant for it to register temperature. If the coolant does not touch the bulb, the gauge will drop back to the bottom of the range. On rotaries, the temp sender is high and at the back for a reason: that's the part of the engine that gets the hottest, meaning the front part of the motor was probably a good bit cooler in your case and that the motor was full of coolant.

joshx99
joshx99 New Reader
10/28/08 6:24 p.m.

Sounds good to me. The Neon I bought to use as a DD is such a disappointment after driving the FB for so long.

joshx99
joshx99 New Reader
10/31/08 8:32 p.m.

Well, good news. I put in a new radiator yesterday, and the car seems to have no issues at all, other than me not being able to shove the fan shroud back in. Compression and everything is good.

P71
P71 GRM+ Memberand Reader
10/31/08 10:13 p.m.

Told you they were nigh on indestructible

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