Afternoon all,

Right, the Fez has been a right pain in the arse lately, mainly with the coolant this time.

Story so far, got the 2.0 in and obviously changed the coolant, then had a pin hole leak from the lower rad hose, no bother I thought bought a new one and changed it all seems fine.
Now i've been getting coolant leaking from the thermostat housing, have to admit that I never changed the O-ring seal on the housing when I put the 2.0 in as I forgot to buy one so changed that over at the weekend. Let it run up to temperature as it was leaking after a drive no leaks present. Also changed the rocker cover gasket as it was trickling oil out of the side nearest the thermostat and mixing with the coolant all over the road outside my house (I'm sure the neighbours must hate me )

So, anyway, let it get up to temperature (needle was up in the O) but the top rad hose never got hot. Does this mean the thermostat is goosed and not opening?
Also, there is a hell of a lot of pressure in my coolant system when the car is running, the top rad hose felt almost solid when I was checking it for temperature. Also, if I run the car for 30secs - 1minute then switch her off and open the coolant cap there is a big hiss as the pressure escapes.

I'm wondering if the pressure is my problem and it is just finding the weekest points to burst out of? If so, whats causing it??
I've read stories of cracks in the head allowing exhaust gases to mix with coolant and building up pressure, anyone heard of a Fez doing this?
Or could it be head gasket doing the same? No mayo on oil cap or over cams that I can see (had the rocker cover off remember ).

I'm pretty sure I used the thermostat housing from the Fez and not the Mondeo as I tried to use all sensors that I knew were working. The cooling fan does come on eventually when driving and the needle has never been passed the N in NORM. Although it does cool down quickly when the fan does come on, which if there is no water going through the radiator adds even more confusion to the mix

Cheers for your input, I'm sure I'll eventually get this thing running how I want in time for selling it in the summer

Paul

Hi mate whip the thermostat out and stick it in a glass of boiling water and watch it for a couple of mins see if it opens,, if it dont open its fooked and probably causing the problem no harm in flushing the rad through with a hose at the same time as it could be blocked :O)

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THE DON..... DON DIGGLER

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THE DON..... DON DIGGLER

Hi Don,

Cheers for the replies.
I'm going to just get a new one from Ford and replace it I think, for all of the cost and it'll pish out coolant taking it off so might as well only do it once

As for the pump change, yeah, put a fiesta one on.
Pretty sure if it was a Mondeo one on then I would have all manner of problems with it over heating rather than this, but good shout

Cheers

Paul

When you refil the system and get it up to running temp, do you leave the cap of the whole time? I would of said it's a thermostat or a blocked rad problem, do the heaters inside get hot?

Hi Tonwah,

No, cap on as it would normally be.
Inside haters heat up fine and dandy, just the top hose and rad doesn't seem to heat up.

Picking up new thermostat and gasket along with a new coolant resevoir cap as my thinking is the pressure should come out the cap before it starts bursting hoses and seals
Paul

should always have the cap off until the coolant is almost up to temp, while gently revving the engine every minute or so, then fit the cap, then after a few minute the fans shold cut in.

also while the coolant system is empty, i woul;d stick a hose puipe down the top hose and flush the rad out

Tony

Sorry, bit of confusion I think. When I re-filled I had the cap off but I'm talking about in general driving now.
The 2.0 was put in at the start of January.

Anyway, was driving home from the shop last night and the needle pinged up the way and steam was all around and a quick inspection under the bonnet shows that the coolant is now empty.

So, either a hose has burst (fingers crossed) or the head gasket has burst (MLS so I would hope not!!) but will have a proper look tonight when I get home.
Not sure if the steam coming out the back was from the exhaust or just travelling under the car and out the back as I was moving at just under 30. Was definitely steam coming out from under the bonnet when I slowed down.

The joys, the joys.....

Well, finally got out last night to have a look and the thermostat to heater matrix hose has split good an proper.
So, Samcos are ordered, new thermostat is in, new expansion tank cap on and I'm going to get the radiator out and give it a good flush in all directions.

Now, my question is, will the expansion tank cap relief the pressure before the samcos/radiator burst?
I'm pretty sure it will but just want some opinions.

I'm hoping that the thermostat is whats causing the increase in pressure but I'm still not convinced. Will have to find someone to do a block check for exhaust gases in coolant.
If this doesn't fix it or something else goes wrong then there will be a nearly new set of samcos for sale along with any other bits that I don't break in a rage

Paul

Have a gas test done on the coolant to see if there is exhaust gases in the coolant, that would cause hoses to expand and pop like a ballon if the head/block had cracked or HG failed, or could have a UV dye put in the coolant and then check the exhasust and cylinders with a UV light

Does the coolant in the header bubble at all? That would indicate the head gaskets on it's way out, also compression test would show if any cylinders are loosing

Best to check soon as if it really let's go you will know about it

Right, been digging a bit further and I wonder if I am on to something.

The head gasket kits I got came with a MLS (Multi-Layer Steel) gasket rather than the usual fibre gasket. Now I just thought, woop, thats what Cometic ones are so they must be good but apparantlythey are only meant for the Blocktop as standard.
And, as I didn't ge the head skimmed I'm guessing that my problem lies there.

So, I've just ordered a new head set with a fibre gasket and while the car is off the road with the hoses I'm going to whip the head off and change the gasket over and give it a good look for any warpage while I'm there.

What a ball-ache!!

Paul

hope it comes up trumps! good luck

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fifi

You won't visually see any warpping of the head, it needs to go to a machine shop and skimmed and pressure checked, costs roughly £30-£40 for each but are an absolute must

Hi Tonwah,

Thanks for that, will look into someone near here for it.
Do you have to strip it of cams and valves etc before skimming?

Paul

The cams have to be removed before it can be skimmed but not the valves, ideally if you can afford to, you should have the following machine work carried out to the head:

1- pressure checked

2- strip down, cleaned and rebuilt

3- valves lapped in again to retain cylinder pressure better

4- head mating surface checked for flatness then skimmed only if it needs it and by the minimum ammount
2

Hi Tonwah,

Cheers for the info.
Phoned a couple of places up here, £96 or £90 for pressure test and skim.

Head was stripped down, cleaned and rebuilt prior to going in and valves were lapped in also.

Just waiting for head gasket kit to arrive then I'll get stripping sometime this week hopefully!

Paul