Technical Fiat 500 Twin Air 2012 Coolant Pouring Out of Hole! Help

[SmithyMC]

Hi all,

So been a long time follower of this forum and got lots of fixes over the years!

I have never seen this before but my Wife's Fiat 500 Overheated yesterday and the result is that some sort of plug or stopper has blown out as can be seen in pictures below and water just runs out. I possibly think Cylinder head gasket has blown and pressure forced it out.


I cannot find any info on such an item metal stopper or plug and have not got the item that blew out. It appears that it must have been seeping already due to the yellow greencoolant residue below the hole.

So hear goes

Pic 1 is the Hole

Pic 2 is the water gushing out

Pic 3 I found on the Forum showing a Twin Air with the said plug?

Pic 4 I found another Twin Air Collant Diagram but do not know if any of the parts are the same Only Part no 15 may be something? The hole goes in someway

Any Help here would be much appreciated. I know its a Garage repair but would like some sort of guess of how bad it could be

Many Thanks for any Help

 

[jrkitching]

Hello and welcome to the forum.

Sorry it's in these circumstances.

Difficult to know how to advise, as it's unusual to see this kind of failure on a TA engine.

I'm wondering if the loss of the plug was the cause of the overheating, or a consequence of it. Either way, if the engine has been run for a significant time without coolant, the prognosis isn't good. There's not much technical repair information for this engine in the public domain, most independent garages probably won't have any experience of working with one, and the cost of a franchised dealer repair could easily be more than the value of the car. Salvage engines, if they're any good, aren't cheap.

If it were mine, I'd start by fixing the obvious damage and see how it runs from there.

 

[SmithyMC]

Hi There, thx for your Prompt Reply,

My good lady was sitting stationary in a que of traffic when the water left via the blown plug. She pulled off the road straight away when all the steam rose off water hitting the exhaust.


The coolant resevoir is brown showing signs of water being overheated by gas. The Oil is fine normal colour with no residue.

Vehicle is driven every day of its life so we had no water problems till now and engine still sounds pefect and not missing when it went on the trailer and today.


Yes for me its bung up the the hole and see what happens under close supervsion but no idea what part no it is and do not want to go to Fiat of course as you say with a car value of around 3.5k we are hoping cylinder head gasket trouble at best.

As you say looks like a concave pressed metal Plug

My local Garage will look and do but wish I could buy the plug.

found clear Pic of plug on a twin air block.

Edit - Answered my own question now as its Engine Core plug / Welch plug / Freeze plug / Expansion plug and can be purchased thx


Thx again Richie

 

[jackwhoo]

Generally the plug you are after is called a core plug.
Measure diameter of hole , look online for a core plug of that diameter.

Google core plug , fitting a core plug and replacing a core plug . Hopefully helpful videos to be found.

Dis coloured coolant is usually a sign of coolant not being replaced at correct intervals leading to corrosion.

 

[jrkitching]

with a car value of around 3.5k

That's forecourt money; if you were selling, you'd likely get around 2k from the trade, perhaps 2.5k if sold privately. I'm hoping for you that the repair will cost a lot less than that.

Generally the plug you are after is called a core plug

I wouldn't worry too much about trying to identify the specific core plug. Generic core plugs can be bought in sets; I'd expect any independent garage worthy of the name to have one in the cupboard.

 

[vexorg]

Generally the plug you are after is called a core plug.

Are you sure, it looks a bit small to be a core plug

 

[jackwhoo]

Are you sure, it looks a bit small to be a core plug

Hi,

I am certain.

Core plugs are available in a large range of sizes.

Cheers

J

 

[John202020]

Buy a genuine Fiat plug, won't be that bad, replace refill fluids and do a compression test, go from there, if they will tell you ask fiat what the compression value should be, some are more helpful than others?

 

[SmithyMC]

Thank You ALL for all the responses

Yes 10mm Core plug / Welch plug / Freeze plug / Expansion plug. But will measure precisly tomorrow again as would hate it to be 9.5mm.

Slightly worried that the side walls of the plug are still there will be closer inspection tomorrow but could not feeel any jaggy edges inside.

My Local Garage for me tomorrow.


The Car has full Sertvice History - All services done on time and collant checks forever by our man. Will let everyone know the update to what caused it.

You have as always been very helpful on here and Thank You All again for the responses.

Richie

 

[varesecrazy]

Thank You ALL for all the responses

Yes 10mm Core plug / Welch plug / Freeze plug / Expansion plug. But will measure precisly tomorrow again as would hate it to be 9.5mm.

Richie

Got any twist drills..??

Use the shank of the drill as a plug gauge

Thats far more accurate for gauging what diameter you are trying to plug

 

[vexorg]

Unusual for a plug to go with overheating, the pressure release on the coolant cap should have gone first.


Can you fit them in situ? usually takes a bit of force with a big hammer

 

[roverp480]

If the edge is ragged it might have corroded through , especially as you say the sides of the cup are still there. It is unlikely to have "blown" out in my view.

 

[vexorg]

It is unlikely to have "blown" out in my view.

More likely rotted away with Fiat's usual attention to rust

 

[Ralf S.]

My guess is it just worked its way out, but it's a bizarre one for sure.

I doubt it froze and "partly" came out in the past, since it has to be ***** cold to freeze the coolant, even if you had pure water in there, never mind water containing any trace (old/new/over-diluted etc.) of anti-freeze.

I would just fit a new core plug. Loctite it in/howver it's supposed to be dressed and then just top up the coolant and see what happens. Head gaskets are quite tough so it may have survived the over-heat.

My guess is that car over-heated after the fluid ran out rather than the plug got blown out by overheating... engine blocks are designed not to cavitate (local hot-spot boiling) and even if it did, the system should be purging gas into the radiator or into the expansion tank. It couldn't accumulate in the block and build up so much pressure to eject the core plug.

On the other hand.. it's a strange one. It'll be interesting if anyone can find out what happened..


Ralf S.