G'day.

The Magna has been losing coolant for ages. Sometimes a little, sometimes a lot. I thought it was due to the ancient radiator cap, so I replaced it with a new one which had rubber that wasn't crumbling.

Recently we drove it a couple of thousand km without issue. Well, it needed an oil topup, but that was it.

Yesterday I did one of my regular rounds checking all the vital fluids in the cars.
I look at the coolant overflow tank. Empty. Hm. Pop the radiator cap. Nothing there. Hmm...

Because I was out of coolant I dumped a couple of litres of water in and ran it for a bit with the cap off to watch the level. No change. Actually went up a bit. Whatever. At this point I started making a few mental connections.

I had driven it earlier that day and it hadn't been raining. Yet it had been spitting water out the exhaust this time round when I started it. I have seen this many times now, unfortunately.
Earlier on in the day when I took it for a little drive (maybe 2km to the shop and back) from the moment I started it the revs were higher than normal.

This combined with the water in the exhaust and low coolant reminded me of one of my most hated demons. Vacuum leaks. It started to occur to me that the water preheat in the manifold (EFI TN) could be failing and the motor could be sucking coolant in, and when it sucked up enough coolant, it could have started sucking air.

Of course I could be totally wrong and it could be the head gasket. But there have never been any signs whatsoever of oil / coolant cross contamination. In that circumstance too wouldn't there be bubbles in the coolant from gases being forced into the cooling system during the compression stroke?

I'd really love some input on this. It all seems a bit strange.

get a pressure test done on the cooling system and a monoxide test and that should show up any leaks

check these

the thermostat is opening
the thermo fans are working
hoses and clamps are ok
look at the welsh plugs for corrosion or leaks

check these

the thermostat is opening
the thermo fans are working
hoses and clamps are ok
look at the welsh plugs for corrosion or leaks

The car reaches operating temp quickly and doesn't overheat so the thermostat is probably fine.

The thermo fans are functional.

All hoses and clamps are fine.

Haven't checked the welsh plugs yet. To be honest I have seen no signs of leakage. The only place water comes frm is the exhaust. But I could be completely wrong about what I am seeing so I will give them a check.

Perry has very good suggestions too. They'll have to wait a little while though unfortunately.

water from the zorst may only be condensation

I can do the pressure test if you want, does not take long.

Doubt the preheat is your issue as you would get the pressurised coolant/water sitting there when the engine is off, when you go to start it it would run like a pig and be hard to start.

These have issues with cracks near the exhaust ports, is common. A prelacement head is usually the beat bet and while you are at it grab an M9 head (I have a few of them here)

From my own experiences. The expansion tank rubber, if its out of shape or got more holes than it should, your radiator will push water out until it overflows out of the expansion tank, but with the extra cracks an holes, it will not allow the coolant to draw back to the radiator as the car cools. I replaced this with a new one and bingo, no more water loss. All my magna's (3 of them) have some moisture coming from the exhaust and I was told this was common for vehicles with catalytic converters. Had all the tests mentioned above and all were good, although we did find out that the gas test can give false readings if any type of chemical weld substance has been used in the coolant system to plug leaks etc.

Just my experiences though, there may be more to yours though.

If you value your car, get the tests done though, for peace of mind and to save heartache at the most inopportune time.

One of the radiator exhaust gas tests costs bugger all at a radiator shop, you should give it a try I think. $20 dollars if I remember right.

Another check is to start the motor with the cap off (or take it off when the motor is warm carefully) and let it warm up. Watch the radiator water through the cap for bubbling. Head gasket bubbles will come through as usually a very fine small bubble which looks like cloudy water.

If you value your car, get the tests done though, for peace of mind and to save heartache at the most inopportune time.


Sorry about the thread necromancy, but the worst did happen.
I wasn't in the car but apparently it started vibrating then CLUNK. And that's all.
Went and retrieved it with a car trailer today.

On taking it off the trailer today there was signs of coolant dripping from... somewhere.

When I got to the car today, maybe an hour after the incident the motor was still hot enough that it was ticking.

The trouble is there are even odds on overheat and oil starvation seizure. Yes the oil level was fine,but recently it has been suffering oil pressure fluctuations.

There has never been any oil / coolant crosscontamination.

Tomorrow I'm going to see if the engine can turn over. I figure at very best the engine will have a shortened life and will need headwork / replacement.

I can get secondhand engines for about $300 from the wrecker here, but that's about $300 more than I have right now, and I don't have a crane anyway.

So if it doesn't have a spun bearing or terminal damage I might be able to get it chugging a little longer. Maybe.

Have you worked out what you want to do with the car yet, as I said to you a few weeks ago, best I think just to do the top end and drive it until you can afford a better car as you will have to do the rust etc to make the car 100% again.

Have you worked out what you want to do with the car yet, as I said to you a few weeks ago, best I think just to do the top end and drive it until you can afford a better car as you will have to do the rust etc to make the car 100% again.

The Magna isn't rusty, and the engine didn't even leak oil and was in stunning condition. Even had new injectors and injector rail.

Well, no matter. That engine isn't going anywhere. I'm going to try to get the timing cover off in the next few days in the vain hope that it dropped the balance chain and jammed the motor, as opposed to oil starvation seizure :(

I wonder what happened to it. It still had a full complement of oil, and coolant wasn't lacking.

No sign of crosscontaminated fluids either. The next few days will tell.

The irritating thing is that we have three cars. Two are registered. The unregistered one runs best. The remaining one (EA Falcon) is on deaths door, and the Magna is the only auto. My partner was going to go for her driving test in the Magna in a couple of weeks but it decided to cark it.

I'm considering seeing what's going on in the chain cover, and if it oil starvation through chain drop, drench everything I can in oil, try to free things up and do the chain. If it doesn't drop its guts in ten seconds, consider it a conditional success until I can find a real solution.

Sound feasible?

I know I'm just replying to myself, but I started to take a little bit of a poke around today. Don't have time to do any real work.

Pulled off the rocker cover. There's still a sheen of oil on the cam and other contact surfaces. Everything looked pretty reasonable really.

Spark plugs all looked nice and healthy too, although due for replacement. No contamination on them.

Pulled off some other bits in preparation for the job. It at least gave me easy access to the balance chain adjuster. Loosened the bolt and gave the tab a push. Went straight down to the housing. Correct me if I'm wrong, but that seems like a pretty good indicator that there is no chain on there anymore.
Slowly getting a better idea of what the nature of the beast I'm dealing with is. I'm desperately hoping that it was the chain jamming everything up and there isn't too much peripheral damage.

Oh yeah, the oil smells like exhaust. Depending on what's wrong and whether I need to pull the head it might get a new set of rings.

Have you pulled the sump off yet?

Have you pulled the sump off yet?

Nope. not yet. Have to put it up on stands first. May I ask why you suggested it? I've never pulled down an Astron before. I can understand checking for things like a siezed conrod, but what else can I see with the sump off? Is it possible to see the bottom of the chains?

I have a Gregory's but you know how the pictures can be at times on them.

Nope. not yet. Have to put it up on stands first. May I ask why you suggested it? I've never pulled down an Astron before. I can understand checking for things like a siezed conrod, but what else can I see with the sump off? Is it possible to see the bottom of the chains?

I have a Gregory's but you know how the pictures can be at times on them.

You'll see the bottom of both the chains and you'll find all the broken bits that have gone to the bottom of the engine (ie chains and chain guides).

Sorry, was thinking of someone else lol.

I have a spare block here if you are in vic and want one for free lol

Alright. Here's a bit of an update:

I got the sump off today. I think the previous owner was either a gorilla or Superman. What I saw was strange.

First, the balance chain was still there. I reckon it was probably loose and slipped, but my earlier check of the adjuster removed any evidence of that. D'oh.

There was also surprisingly little contamination in the bitumen... I mean oil. I could see some fine metal powder resting in the bottom of the droplets of oil clinging to the big end bearing bolts.

There were a few metal shavings on the block near #4, as in maybe 3 or 4.

There were a few chunks of metal in the sump, and a few shavings. I suspect the chunks were from the chain guide. Second guess a worn and mangled bit of escaped ring. Third guess bearing bits.

What else... Topend seems perfectly fine.

Now the biggest, weirdest thing of all. #3 conrod had a nice coating of oil on the big end.
#1 and #2 only had a dribble. The rest of the big end of the conrod was disturbingly clean.

#4 looked totally clean and factory fresh, as in perfectly clean external surfaces with no sign of that black sludge of oil.
Did they get so hot they vapourised all traces of oil and carbon yet somehow avoided heat discolouration, or what?

I haven't finished with removing the timing cover. I was tired and ground to a halt when the Gregorys told me to remove the through bolts from the front and back torque stays. What does that mean?

I also received a bit more info of the circumstances. The car was driving along, and started cutting out like it was getting low on petrol. My partner pulled over and stopped, ready to turn around to go to a service station when the motor stopped with a clunk.
Just before that it sounded like the topend was full of pebbles.

The point at when the engine stopped gave me a good hint as to why the amount of actual damage I see is so minor.

Thanks for the offer Madmagna. I hope I don't have to take you up on it :)