Coolant leak? 1999 Fiesta 1.25 Zetec beside spark plug

zg3409

Hi,

I have a 1999 1.25L Zetec petrol Ford Fiesta with 120,000 miles on the clock. While replacing the HT leads, I noticed a lot of liquid around the spark plug on the passenger side of the car.

I sucked all this liquid away with kitchen roll, and it had an orange tint. I assumed it was a coolant leak. From reading online some people say that windscreen washer water and rain water commonly gathers here. However there is sound deadening material under the bonnet which would not allow it to leak on to the engine.

To check if it was an engine leak I dried it all up, and then went for a quick 10 minute run around the block. Initially I could not see any leaking, so I then left it to sit for a little while (20 minutes) and took the photo. From what I see, it looks as if the large allen head bolt is leaking, but I don't think this is a frost plug and I could find no mention online about this problem. The engine was quite cold, so I don't think any water leaking down from gaskets would have filled the bottom and then evaporated. The coolant was below min and I filled it and I am keeping an eye on the levels.

I have also included another photo of the other 2 spark plugs, which are dry which shows the layout and how it should look.

The photo shows the large allen nut just filled with liquid (water ish)





So
a) Where do you think the leak is coming from?
and
b) What could I do to test more and fix it?
and
c) Is it a job I should attempt myself?

Thanks in advance for any help/advice.

Alanstrainor

Is your coolant orange? Or is the orange tint from rust? How is your coolant level? Did the coolant have a smell to it? It's usually sweet to smell, and is pretty recognisable.

zg3409

Alanstrainor wrote: »

Is your coolant orange? Or is the orange tint from rust? How is your coolant level? Did the coolant have a smell to it? It's usually sweet to smell, and is pretty recognisable.

I did not smell the liquid, but I still have the kitchen roll so can check. It was very orange and the coolant is orange. As already said the coolant was a little low so I topped it up to the max line.

The main thing I want to know does that large allen headed bolt fail and if so is it easily fixed?

zg3409

I found some info online (newer model Fiesta)

corroding core plugs between the plug-wells in the head. [Usually caused by lack of anti-freeze changing.]

look through the hole at the space between the plugs you will see a large allen headed plug this is screwed into the water jacket "the threads leak" that may be where you water is coming from if so they will need removing cleaning and resealing

The ones that I've done have often been so corroded-in that they've needed a machine-shop to grind them away and re-tap to take a 1" BSP plug.

Found it, leaking core plugs. Stripped out cleaned, re-sealed sorted - many thanks all.

http://www.honestjohn.co.uk/forum/post/index.htm?t=64138

So it may be the threads leaking, rather than the centre rusted (although mine does not look like threads). I think the next step is to re-test it again and see if the water is coming from the threads or the middle. I am quite hesitant to try unscrewing it after 17 years. I am leaning towards sealing with blue gasket sealant, especially if it is the middle of the allen head, leaving the plastic engine cover off, and keeping a close eye on the problem. Opinions?

zg3409

I tested the leak, and it does seem to come from the middle of the hole and is coolant. I cleaned the hole with kitchen roll and cotton ear buds. I then applied Loctite SI5699 which is like gasket rubber, but is silicone based and designed for coolant gaskets. It is similar to bathroom silicone but intended for higher temperature use and resistant to coolant.

http://www.loctite.co.uk/loctite-4087.htm?nodeid=8802627125249

It is available for 7 euro in a small tube in halfords. I made sure to overfill the hole as the top of the hole is less greasy and should seal better. I will try update with a photo and results, but I am going to leave it settle for a few days as that is what is recommended as it is slow to set and I used a large amount.

I will try update with a photo and long term results.

Muckie

...

jca

Plugging the hole from the outside never works as the liquid is still escaping and pushing the plug out. One, and only one can of Radweld might be more successful. I certainly can understand your reluctance to unscrew a 17 year old core plug. I'd try the Radweld.