Bad head gasket?

[Safety Guy]

I noticed more tapping noise from the top of my engine this morning. As I drove Aqua and she warmed up, the heater did not blow warm air. Totally cold after plenty of warmup. The tapping noises came and went, but my oil is full and no oil light ever came on. The car is running hot and my radiator overflow bottle is full. Radiator fluid looks kinda nasty.

I'm thinking my head gasket job two years ago is coming undone, but before I take things apart, I could use some advice on what to check to make sure it isn't something else.

In a few more minutes I'll open the radiator cap after she cools done completely.

Thanks,

Karl

[Movin]

If your heater core has been through all that it probably needs flushed or replaced, its not
easy to throw one in so check really good first!! Also..assuming you already checked the t stat.

If the jug is full and its low fluid in the radiator your cap and hoses to jug might be plugged up.

I would look for corrosion and warps in the aluminum parts that bolt to the head before blaming
a new headgasket for leaks.

For clicking try overfilling the engine oil with 5 30 oil by 2 quarts then idle and slow test drive if
needed to see if clicking goes away. This tests for sludge and oil pan dings that block the sump
enough to draw air in at the oil pump. Drain the 2 quarts or change the oil when done checking.

Good luck!!

[Safety Guy]

Thanks Movin.

I was getting good heat a couple days ago, so this just came up since yesterday it seems. Heater core should be fine, as I flushed it with water when I rebuilt the car two years ago.

I just took off the rad cap and the level is way down. I added a .5 liter bottle of water without seeing the level rise above the radiator tubes.

If I fill it back up with water and antifreeze and let it idle, should I be able to see where it may be leaking if its not the head gasket?

There is green fluid around the transaxle housing, but not all where the overflow would have sprayed it. On the other hand, the other end (front) of the engine is dry. Only the transaxle side of the engine block has greenish fluid on it.

I suppose it could be a hose leak, or a bad thermostat housing gasket.

Finally, the t-stat sensor in the housing has a loose electrical connection where it hooks to the wire. The wire's not loose--it's the electrical spade part loose inside the fitting. Could this be leaking?

Thanks,

Karl

[Safety Guy]

As for the clicking sound, I interpreted that to be a sign of overheating: the oil was not doing so well in the excessive heat.

Karl

[zoom zoom]

can you see if the green fluid is leaking around the head/block mating surface, or is all the fluid just down on the tranny? I had antifreeze sitting on my 626 tranny, but it was leaking from the IAC valve.

[Safety Guy]

Matt, I think it's the little "U" shaped hose that connects the bypass pipe to the T-stat housing. I'm gonna go get some new rubber in a few minutes. The green tinge does seem to be on the head as well as the block, so at this point I don't think it's my head gasket.

If it's not the little hose (mine's pretty decrepit looking and older than sin), it would probably be the upper rad hose (which is tight and looks okay) or the t-stat housing itself.

The looseness of the sensor should not be a problem. I looked at a new part and there's no joint to leak on the inside part.

I'll let ya know how this goes in an hour or so. Fortunately, Prettystiva will drive me to the AZone, which I could walk to anyway (less than a 1/4 mile).

Thanks,

Karl

[Safety Guy]

I put on the new rubber hose and added more coolant. Started her up and...saw a leak spurting out of the bottom of the new hose. Stopped engine...tightened clamp. Restarted...no leak so far. Gonna test drive in a few minutes.

I think I got it. More news in a few...

Karl

[Safety Guy]

Added more coolant and water to top off radiator just now. When I opened the cap it spurted out under pressure. It hadn't been running more than a couple minutes and that was twenty or thirty minutes ago. Is this normal?

Karl

[Safety Guy]

Just finished a ten to minute test drive and engine idle. It doesn't look good.

Engine still taps. Reminds me of when my oil pickup tube came loose and the engine wasn't getting oil. Only the oil light is not on.

Engine is warm, very warm. Radiator cap is very cool. I am getting heat inside. The radiator overflow is almost full! (I had put less than half in the overflow when I finished up earlier.)

Worse, at the end when I had it idling, the engine seemed to slow down and get quieter, then seemed to want to stall out! I turned it off before it did.

What might happen inside the engine to cause all of this? FWIW, my new hose is not leaking now.

Afraid to run her more. I'm thinking a bad head gasket again, pressurizing the coolant system.

I'll wait an hour or so before taking off the cap to check rad fluid level.

Karl

[crazyrog17]

Bad head gasket?

You said the overflow tank was full? When the radiator is under more than 13psi, the radiator cap lets the excess coolant into the overflow bottle. Maybe your head gasket is allowing combustion gasses into the system and it's being relieved there. I'd hate to assume though; that means an new gasket

[Safety Guy]

Look at my post above. That's what I was thinking Zack.

Would a bad head gasket also lead to some upper end oil starvation?

Karl

[zoom zoom]

are there any bubbles in the radiator? id probably put a thermostat in there just to be sure its not faulty

[tkannegaard]

sounds like a blown gasket to me compression to coolant system, if it is make sure to check head did'nt warp with all that heat

[mintFestiva]

Doesn't sound good. If the head gasket were allowing oil to leak out substantially, you would be losing the pressure needed to get it to the top of the engine.

On the bright side, if it is the head gasket, parts (exhaust manifold gasket, intake manifold gasket, and head gasket) are only going to run you about $50 at Advance Auto Parts(I just priced it recently).
That's of course assuming no resurfacing is needed and there was no further damage.

[Movin]

Your thermostat is stuck closed from OH caused by the leak..low level.
this makes it really hard to burp air from in the block and can get really
hot without showing much on the gauge if air is caught around the sensor.
Replace the T stat.

fun stuff !!