[Fordpoorman]

I have a 1999 SE Sport with the 2.0 SPI SOHC engine (VIN P). I have read alot about how the number four cylinder likes to drop the valve seat. I bought the car in 2017 with about 80,000 miles on it. It now has 116,000 miles and running great (2022). Not knowing the service history, shortly after I bought it, I replaced the timing belt and water pump. The old timing belt looked fine, but the water pump did not. The water pump has a backing plate on the impeller and it was severely corroded to the point where it looked like swiss cheese. What I suspect may be happening is that metal particles from dissolving impeller along with your usual crud after 80k miles or so are clogging up the cooling passages in the head aroung the number four cylinder, or any of the other cylinders for that matter.This could potentially cause uneven heat buildup in the head, causing it to warp enough to pop the valve seat out. Before I changed the water pump, I flushed the cooling system with radiator flush (Blue Devil for example). It looked like it originally had the Ford Gold coolant. I replaced it with universal green coolant and it has been fine, though I offer no guarantees. It runs great. If it blows, I will post it. Hope this helps!
MAGA

 

[Escort230]

Hello, thanks for your post. I read a similar article online somewhere about dropping the valve seat.
I didn't even know such a think was possible! Now I've watched a few videos and see what they are talking about such as this one.

I like you have the 1999 SE sport now around 120K miles.
It's always runs a bit rough, and occasionally will misfire start running on 3 cylinders.
Stopping and restarting seems to resolve the issue.
Also been getting CEL for something to with the O2 sensor.
I worry there is something wrong with it, but other than the 02 sensor code, nothing, and it went out
after a while.

I purchased the timing belt and water pump (Gates) some time ago, but have not gotten around to installing.
23 years on the belt, yikes ! I did a radiator drain and fill recently didn't see anything out of the ordinary.
Didn't use a flush product though. Just wanted to make sure head gasket wasn't blown, and no idea when coolant was replaced last. I acquired the car with ~90K original miles some years back, and now it's around 120K.
It's become our 'go to' car with the price of gas lately. Goes twice as far as our SUV.
So how can I determine if the valve seat is hosed?

 

[Joey_Twowagons]

A compression test might detect it I guess.
Pretty cool to see the disintegrated piston in the Escort engine in the posted video, amazing that the cylinder wall was still okay.

 

[Escort230]

I see you can get a Bluetooth Boroscope online for like $20.
Uses your phone for a screen. Brilliant!
Get a look inside those pistons perhaps.
But what to look for? Any advance signs?
Looks like most if not all seem to crap out around 120K miles.

I'm at 110K. Do I have this to look forward to? Does it happen in all cases sooner if not later?

 

[Fordpoorman]

I wish I knew how to determine that for sure. You can try the compression test or the boroscope. I don't personally know what to look for on the boroscope. You might look at all 4 cylinders and see if there is any difference between them. I have seen posts where a car has 250,000 original miles with no head work done. I would definitley give it new plugs and wires and see if it corrects your misfire, if you haven't already. These engines are not know for having a smooth idle, mine included. I suspect from what i've read that this is just the way these engines are. I have read that just before the seat drops you will have an unusual ticking noise, and it seems it likes to happen on start up.
In my case, with the condition of the water pump impeller, you are not going to get good coolant flow. I would think that would make it alot more likely to have your head get too hot and cause the valve seat to come loose. Hope this helps!