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Saturday, 6 May 2017

Mondeo ST24: water pump replacement

My car has now hit 157,000 miles. It's also 19 years old and the bodywork has seen better days. The car still goes well but from time to time certain age/wear related problems arise. Last week I returned to my car to discover a puddle of water on the floor under the front bumper. Last time I had something like that, the bottom connector on the radiator had cracked. That was last summer and the remedy was to fit a new radiator, which I did, last October. Seeing this puddle reminded me of that, and filled me with dread; could my new radiator have sprung a leak?

I happened to have a two litre bottle of water in the car. I used that to brim the expansion tank and then drove home. Once I'd pulled up, I jumped out and look underneath at the front. I could see a trickle of water dropping down from behind the engine under-guard. This was a relief because it meant the leak could not possibly be coming from the radiator. On the other hand, what was leaking? I popped the bonnet and had a look around. I could see drips on the bottom edge of the water pump. This was interesting because I had fitted that water pump as a precautionary measure when I first bought the car about 5 years ago. As the car has done about 55,000 miles since then, I was planning on replacing the pump and already had a shiny new one in my spares pile. That night I swapped the pump for the new one and started the car up, hopeful that the leak would be sorted. Here are some pics I took:








Alas, it was not to be - the leak was still there but I could now see, with the aid of a torch in the dark, that the leak was coming from the water pump housing. And that revelation led me to this discussion on the TalkFord website:

V6 Water Pumps

I therefore reviewed the pictures I had taken. The first one, which appears above and which I took by holding my phone down into the space next to the pump, shows clear damage in the housing. I could have saved myself some time by actually having a look at the pictures I had taken...

So, the next day I removed the (new) water pump together with the housing, and split them apart. Now, removing the pump/housing from the car is technically straightforward. I removed the air filter box and the battery to make some room, and the belt, and that just left three 8mm bolts and three spring clips (on the hoses attached to the housing) to remove. The bolts were easy enough (they have to come out when replacing the water pump, anyway). The hoses and clips on my car are, I think, original. They were a total bastard to remove and it took me about an hour to do all three. My hands are still sore from the experience. Anyway, with the housing off the car and the pump removed, I was presented with this:



I'd noticed that shiny disc was in the wrong place when I changed the pump the night before but I didn't think it was significant. But having since seen the posts on TalkFord, I now knew that the disc was in the wrong place and was likely to be the cause of the leak in the housing. I removed the disc and turned the housing over, looking for some sort of hole. This is what I found:








So, the shiny disc had worn a tiny hole in the housing. The next question was what to do about it? A bit of research showed that some manufacturers sell new pumps that are supplied with new housings. The most frequent "hit" in my searches was the Dolz F149CT for £60 - £100 depending on the seller. I also found the the complete unit could still be bought from Ford. To be honest though, I wanted to sort this for zero expense. I don't know how much longer the car is going to last and I don't want to be spending money on it. So, I cracked open a tube of JB Weld High Heat Epoxy Putty that I happened to just have. The packet says that it is good for cracked engine blocks so I figured it could handle a bit of hot water, like that which would be found in a water pump housing. This is my repair:





I used the putty to re-fix the shiny disc to the housing, and also fill the groove made by the disc when it was loose. For good measure, I put a big dollop on the outside of the housing. I waited a few hours before reassembling everything (the putty hardens in less than an hour but needs 8 hours to fully cure). I refilled the system on my car and then ran the engine up to temperature. No leak ;). I've done about 150 miles since then and all seems well.

More soon, no doubt...


D