Technical Changed stuck open thermostat, now looks like head is leaking

[SR71BB]

I bought a 1.2 8V MK2 about two weeks ago. The engine temp gauge didn't look correct to me as it was taking a long time to heat up and sometimes wouldn't after a 20min drive. I plugged in a reader and the engine temps were never in spec, way to cold.

I took out the thermostat yesterday and sure enough it was stuck open. I replaced it and now the temps are excellent and it heats up quick. Needle always in the middle now.

But what was once a perfectly dry engine has some wetness on the other side around where the timing belt sits. It's on the head on the front and rear of the block.

I suspected something might go wrong as it looked like the thermostat was the original one that came with the car and it could have been stuck open for a long time. Now that the temps are higher than before, but within spec, has this exposed an issue with the head? Or could it be something else that doesn't like the new temps? Thanks.

I'll post pictures soon.

http://imgur.com/Tj3VdEe
http://imgur.com/Fdzk6nB
http://imgur.com/CNngX9X
http://imgur.com/Zyul4Cw
http://imgur.com/w5OT8Vk

 

[Ziggy122]

I bought a 1.2 8V MK2 about two weeks ago. The engine temp gauge didn't look correct to me as it was taking a long time to heat up and sometimes wouldn't after a 20min drive. I plugged in a reader and the engine temps were never in spec, way to cold.

I took out the thermostat yesterday and sure enough it was stuck open. I replaced it and now the temps are excellent and it heats up quick. Needle always in the middle now.

But what was once a perfectly dry engine has some wetness on the other side around where the timing belt sits. It's on the head on the front and rear of the block.

I suspected something might go wrong as it looked like the thermostat was the original one that came with the car and it could have been stuck open for a long time. Now that the temps are higher than before, but within spec, has this exposed an issue with the head? Or could it be something else that doesn't like the new temps? Thanks.

I'll post pictures soon.

Usually a stuck stat dont cause leaks
And fitting a new one wont either

It maybe that now its getting upyo running temperature and possibly getting presurised (which it should do)

Its made a weap into a leak

I dowt that the change is related tho

Not got a waterpump thats suddenly leaking everywhere?

Ziggy

 

[SR71BB]

Thanks for the reply.

Sorry I should also say... I opened the oil filler cap when my wife got back with it today and it was cover in foam. The foam diappeared after a quick drive to Asda.

I'm pretty sure it's not the water pump as the wetness is above it and I've just noticed a possible broken seal in the images which hopefully someone can confirm.

It is also still wet around the head which could indicate a leak there to or the oil is just splashing up there from the broken seal?

 

[Scudmonkey]

Thanks for the reply.

I'm pretty sure it's not the water pump as the wetness is above it and I've just noticed a possible broken seal in the images which hopefully someone can confirm.

It is also still wet around the head which could indicate a leak there to or the oil is just splashing up there from the broken seal?

looks more like water than oil

 

[SR71BB]

You might be right.

On the image that looks like it shows a broken seal, something pink can be seen on it which is the colour of the coolant I put in. So it could actually be water and not oil.

 

[Scudmonkey]

From the images you posted it appears to be located just above the water pump...could be gasket around the water pump has failed. might be worth a shufty behind the Cam belt cover

 

[SR71BB]

From the images you posted it appears to be located just above the water pump...could be gasket around the water pump has failed. might be worth a shufty behind the Cam belt cover

Thanks. I'll have a look at that. If it is the pp gasket would it be safe to drive it short distances for about a week until I can change it?

Does it look like a seal is broke in one of those images? Or am I seeing things?

 

[flisko]

you can drive as long as you want if you will keep topping up

 

[SR71BB]

Does anyone know what that circular metal piece is behind the timing belt cover?

The Haynes manual makes no reference to it and when I search online I cannot find anything about it.

It looks to me like it is covering a hole that is for something on a different engine but they use the same block.

The seal on it looks to be broken.

Can anyone confirm if that is a broken seal in the picture?

Thank you.

Edit: Sorry, the forum software rotates the image and I cannot get it to correct it. Right in the picture is up and left is down. Down is forward and up is to the rear.

 

[SR71BB]

I've just discovered how I can upload pictures so here they are. Quicker and easy viewing than having to click on a link.

 

[SR71BB]

Bit of searching and it looks like that round thing I think a seal has broken on is called a core plug.

Can anyone confirm if that is a core plug and if it has a seal? Most sources I've found so far say the core plug has no seal and is just banged into place, while a few say they are fitted with a gasket.

 

[Scudmonkey]

a core plug is basically a metal disc that is jusy banged into place, very tight fitting so no seal

 

[Ziggy122]

Core plugs are there because of the casting process
Its to allow the excess or create an entrance to pour in

Once bored nade into an engine block
Its machined to fine tollerance to match the core plugs

Its conviently right on the waterpump too...

Never had to replace one tbh...

Ziggy

 

[SR71BB]

Thanks. I'll take a good look at it this weekend when I have the time to take the timing belt cover off.

I have another question about the car. Not sure if I should make another thread.

As the car is brand new I want to know everything about it. I have hooked it up to multiecuscan. The phonic wheel is showing faulty when the car is not switch on but OK when the engine is running. Does it need to be reset?

The step motor percent moved from a small negative to a positive. It was mostly positive but I just hadn't to freeze it when it was negative. Do those values look ok?

 

[Italian Job]

Done my core plug by taking wheel off, wheel arch liner off and cam cover off.
You may need to use a screw driver to pierce the core plug then lever it out. Have a new one to hand before you start.

 

[digger58]

"As the car is brand new"

How is it brand new? MK2 Punto in 2017?? If it is then these items should be warranty claims.

 

[Mad one]

Core plugs are also useful if you fail to keep the antifreeze topped up and the engine freezes (even in the uk it can happen) the expanding water should push the core plug out as opposed to cracking the block, seen it happen a few times in the past.

 

[Scudmonkey]

"As the car is brand new"

How is it brand new? MK2 Punto in 2017?? If it is then these items should be warranty claims.

2nd Hand but....but to him it's brand new as he not had it long...

 

[Scudmonkey]

Core plugs are also useful if you fail to keep the antifreeze topped up and the engine freezes (even in the uk it can happen) the expanding water should push the core plug out as opposed to cracking the block, seen it happen a few times in the past.

Saw it happen on a Mates Capri some years ago, idiot didnt have antifreeze so of course the engine froze....and of course of all the core plugs it had to push out it did the one on the rear of the block....which meant either engine out or gearbox off as the rear core plug is inside the gearbox bellhousing :devil:

 

[digger58]

Fords had a habit of core plugs hidden behind flywheel/bellhousing, did it on their tractors as well, really helpful when one springs a pinhole leak in the middle of harvest time!!!!!