Technical Is my headgasket gone?

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Technical Is my headgasket gone?

meshgrid

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hi,
coolant is bubbling in my expansion tank when revving. is my HG on its way out?
i looked through other threads, and they were mentioning losing coolant, smoke, overheating etc. my car doesn't do any of that; vent comes on and off fine, but there's bubbling in the expansion tank when revving.
i went for a drive on some hill roads the other day (so, shifting near rev limit etc), and noticed afterwards that a tiny bit of coolant came out of the tank. this doesn't happen normally.

i haven't yet tried to bleed the system; i'll try later today, but i wanted to see what you guys think.

here's a recording with contrast bumped up so you can see the coolant better (sorry, can't post actual URLs yet and can't embed video):
streamable com/gkvvmz

thanks!
 
Hi,
By vent coming on and off normally I think you mean fan for radiator starting and stopping.
At first look it appears fine to me.
If you have a return coolant pipe (degassing pipe) going to header tank as well as a header tank pipe, it could just be normal flow through return pipe when engine at full temperature.

However if your engine starts overheating or needing regular coolant top up you need to look further.
 
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Thinking further on your video if you had that amount of coolant movement in header tank caused by a head gasket failure I'm sure you would have a lot of other problems plus massive overheating.
 
hi,
coolant is bubbling in my expansion tank when revving. is my HG on its way out?
thanks!

Hi :)

From memory these tanks all have a return feed.. so there is a flow of coolant within the tank..

Personally .. I would just keep a watchful eye on the levels of both coolant and oil

They will give you an accurate indication of any issues ;)

Bleeding..?
unless you have stripped and refilled the cooling system recently
There should be virtually no trapped air to remove ;)
 
sorry, forgot to post car details:
seicento sporting 1108 spi, 09/2000
there is a return pipe to the tank, and the video above was made with a warm engine.

thanks for the quick replies! i'm still relatively new to (fixing) cars so not yet sure what's normal and what isn't.

one more question: if a seicento spi overheats, which warning light should i expect on the dashboard? i couldn't find an example anywhere online.
thanks!
 
sorry, forgot to post car details:

one more question: if a seicento spi overheats, which warning light should i expect on the dashboard? i couldn't find an example anywhere online.
thanks!

No problem :)

There is a RED dot.. circular light for 'overheating'

You should see it at the 'MAR Selftest'

When you turn ignition key before starting the engine ;)
 
I'm going back up the don't try to bleed cooling system if everything currently working ok.
 
I attached (i hope) an image of what i get when starting the car (without code light), can you tell me which one? Am i missing a light?

Thanks!
 

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no lights on my rev counter either
 
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You need to find the overheat switch on the engine. It has a single wire going to it.
When you find it , disconnect the wire and connect the wire directly to the metal of the engine. Turn on the ignition and look for a red warning light on the instruments.
 
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so, found the sensor, broke the wire, did as you suggested and found the light, thanks!

anyway i'd now like to put a temperature gauge in the car. i found in an older thread that FAE34060 fits the car, and you get a switch and temp sender in one, which is great.
looking at the data here and here (current sensor), the thread is correct (M16x1.5), the switch point is 120°C new vs 115°C old which is also probably fine.

has anyone done this, anything else to look out for? any special kind of gauge i need for the sensor, or would a normal ebay one work?

thanks!
 
Have a look at recent posts in cinq/sei section .
someone recently found a really neat gadget that plugs into obd port and displays engine temp .
Fits neatly in a sei by gear stick.
Plus you get to keep over temp light.
It will be cheaper and easier than fitting any other type of gauge.
 
saw that, but unfortunately i don't have an obd port in my car, too old :(
anyway with this FAE34060 sensor i should also be able to keep the overtemp light, since one pin is the switch and the other a sender for the gauge
 
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saw that, but unfortunately i don't have an obd port in my car, too old :(
anyway with this FAE34060 sensor i should also be able to keep the overtemp light, since one pin is the switch and the other a sender for the gauge
You should have obd socket in your car it's not that old.
 
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