Another coolant thread...
 

'88 GTU

No white smoke or sweet smell from the exhaust. Some blue smoke on cold start, but that's not my point of concern right now. That blue smoke doesn't smell sweet either, I've smelled it, bleh.

When starting the car cold, after checking to make sure all fluids are topped off and bled, I'll pull the hose out of the overflow and there's a steady stream of coolant coming out. The idle never drops. When the car warms up, or over-warms up (not over heat, just warmer than normal), then the coolant light and buzzer come on. I shutoff the car, carefully remove the caps releasing steam, then refill and re-bleed the system. All is well after that, until the next time I need a cold start and this process repeats.

I've timed it, so the car doesn't get very warm before I shut it off and refill/bleed it, only losing minimal coolant.

It's freaking annoying!

Where can I get CO test strips to see if I'm getting exhaust in my coolant? I don't have Mazda OEM rad caps, but they are new. I don't have a Mazda OEM thermo either, but it is new as well and the jiggle pin is on the high side.

Ideas?

prolly that trick exaust into coolant system leak sounds like a pretty bad 1 too

Wait, are you saying that after the car warms up and you've re-bled the system, that the coolant stops flowing out of the overflow hose and you can drive it around like normal?

Re:
Yes.

Then when it cools down, it pulls some of the coolant from the overflow back into the system. But every time I start the motor cold, I have to go through this process.

That's... weird. I'm no expert by any means, but I'm guessing you are having one of two things going on. First, you have some weird coolant seal leak that closes itself up when the engine gets warm and things expand. I'm dubious about that. Second, something odd is going on with your thermostat and/or radiator cap. It almost sounds like your thermostat is installed backwards. You might want to replace them both, since they are easy and cheap to do and see where that gets you.

I've not been able to find the CO test strips. Let me know if you do.

...and VERY aggravating!

Not only can I drive it normal, afterwards, but I can BEAT on it (I mean hit that rev buzzer in 1st, 2nd and 3rd) with no ill effects.

After bleeding/purging/burping/whatever-it's-called after warmed up, the temp needle rides at about 1/8" - 3/16" from the bottom line of the gauge.

I grabbed all new generic thermostat and rad caps. Generic for now, to diagnose. Problem still persists.

I'll get OEM spec items come payday. Can't drive it now anyways cause I royally f'd up my right shoulder and can't shift.

Sorry to hear that the replacement parts didn't fix, and sorry to hear about your shoulder. What'd you do?

I did some googling for those test strips but had no luck finding any, but I suck at searching.

You may also want to check if you can rent a cooling system pressure test kit from Autozone et. al. If you have a seal problem, it should show it if you do the pressure check with the engine cool.

I was free-running, came off a 12ft drop and botched my roll. I didn't tuck my elbow in and shoulder down enough and just blasted all my momentum into my right shoulder socket. Something went *crack* twice, loud. I swear something broke, but I have 100% free range of movement. Today my muscles are just sore as hell and the joint is super stiff. Figure I prolly just fractured something.

Onto the car:

I did notice that with the new non-oem cap, even after warm it's now still got the same steady stream of coolant going to the overflow as it did while cold. I'm wondering if the cap just isn't long enough to seat properly?? Maybe before when I checked it after warmed up, there just wasn't enough coolant to over flow so I took it as it was fine? Probably.

Need OEM rad cap. Maybe I'll see about grabbing that radiator from the junked FC at the yard. Hell, maybe my radiator is clogged even? Who knows. =/

'preciate the ideas and your CO-strip searching.

Rad cap seats and seals.

Other ideas?

How do I test for exhaust gases in the coolant?

I may have missed something or misunderstood your explanation, but there could be a small hole in the overflow hose/tank, and the engine is sucking air into the cooling system.

Possible, but he's saying that it does that immediately on start, when the engine is cold. The weird thing about that is that the thermostat should be almost completely closed, running the water through the block only. It should be circulating through the radiator much at all. Probably not enough to cause a steady stream.

Jet, what happens when you start the car with the rad cap off?

What you have is a leak from the compression side of the engine (spark plugs to exaust )going into the water jacket thats because either from over heating (burnt water jacket /compression o ring) or you have broken a portion of the o ring groove in the engine ,either way your compression is pushing out your coolant ,because your engine might have 100lb compression but only a max of 18lb in your coolant system

No holes. Markus is correct, though.

The radiator overflows, fast.

Shutup.

lol, j/k. I've been afraid of this.

I don't have time or money to finish this streetport quick enough to swap out. This thing is my DD and I need it. Dammit!

Your going through the samething that I'm goin through... Blown coolant seal... best way to fix is a rebuild or engine swap for a long term fix... Thats what I'm doin...

Yeah sounds like same problem i have= blown coolant seal, suxs maybe someone here knows what pressure you should have, gotta try to get autozone pressure gauge , i think pressure should confirm blown coolant seal, pressure would be higher with blown coolant seal?

To test for exhaust in the coolant:

Take off the rad cap

If you have a steady stream of bubbles then its your coolant seal.

Is that what your looking for?

normally if you start the car with the rad cap off and coolant is gushing out, your coolant seals are gone and a rebuild is in your future.

Yeah, saving now for my rebuild set for this street-port I'm building.

start the car cold and squeeze the upper radiator hose, if it feels stiff and pressurized while forcing coolant out then you have a bad coolant seal. point blank.

if it doesn't feel pressurized and is pushing coolant out of the system then you have a faulty radiator cap.

if it is a bad seal, since it is your DD, you can try the block seal trick to seal it back up temporarily. keep in mind you will have to clean all of that crap out of the coolant passages during the rebuild .

Have two other engines, one of them is my build. The other, well, I was told it is good but who knows?

What's the block seal trick? Does it work on the compression side? I'm not blowing smoke and no sweet smelling exhaust.

Yes, upper rad hose is quite stiff.

I'll give it a shot, but do you think it's worth it if it's not pulling coolant into the engine?

I'm wondering if it will even work if it's compression pushing air out and not vacuum pulling coolant in.

Do I have to let the engine fully cool down between each flush? I'm not scared of hot fluid.

I feel for ya man. I just had a new engine put in my FD because of the same problem you're describing.
The shop (Tri-Point Engineering) did a HC test and confirmed the problem. Solution='s new motor.
Got a new factory fresh motor from Ray and it has been installed. I pick it up later tonight! Can't wait to get my baby back.

Yeah, I know the inevitable is coming, I'm just putting band-aids on it until I can my other motor built. =/