[DialM4Speed]

Also, the proper air bleeding process is to leave the overflow tank cap off and run the engine at 2500rpm for at least 5 minutes.

OK I did NOT do that so maybe that's the problem. I got the thermostat off last night and will put the new one on when I get home. I tested the old one in a pot of boiling water and it fully opened. I checked for corrosion at the CHT all clean. It must be an air pocket some where.

 

[DialM4Speed]

Are your radiator fans operating correctly on BOTH speeds?

Paul

I didn't know it had two speeds so I have no idea.

 

[bcat]

proper air bleeding process is to leave the overflow tank cap off and run the engine at 2500rpm for at least 5 minutes.

IDK. When I try that coolant overflows.

To self bleed, I heard the thermostat jiggle pin should be positioned at 12 o'clock. I had to open the thermostat housing and reposition mine. The factory didn't do it for me.

 

[Paul1958]

I didn't know it had two speeds so I have no idea.

You should find out. Proper fan operation is critical for thermal control.

Paul

 

[pbfoot]

IDK. When I try that coolant overflows.

To self bleed, I heard the thermostat jiggle pin should be positioned at 12 o'clock. I had to open the thermostat housing and reposition mine. The factory didn't do it for me.

Sounds like a small head gasket leak. You should be able to run the car without coolant overflowing from the tank.

 

[bcat]

Sounds like a small head gasket leak. You should be able to run the car without coolant overflowing from the tank.

I can believe it. Fuel trims are usually good but sometimes erratic. May explain that too. Car too old to invest much money in. I wonder how much more life it has ...

 

[pbfoot]

I can believe it. Fuel trims are usually good but sometimes erratic. May explain that too. Car too old to invest much money in. I wonder how much more life it has ...

Lol. If you are handy with wrenches it isn't that expensive. I pay $250 for a cylinder head rebuild at a local shop. Picked up a head gasket and new bolts on closeout at Rockauto. $25.

 

[pbfoot]

In your case, the Duratec with a timing chain is a bit more difficult but still doable.

 

[bcat]

If you are handy with wrenches it isn't that expensive

Mine is a 2001 Zetec. If I had a second car to drive, maybe I would try. Without one, I don't think so.

 

[pbfoot]

Mine is a 2001 Zetec. If I had a second car to drive, maybe I would try. Without one, I don't think so.

Sorry. I am thread juggling.

 

[amc49]

Focus cooling systems use constant flow heater cores and whoppingly better about never clogging up due to it. They flow all the time.

 

[Benjilafouine]

I didn't know it had two speeds so I have no idea.

Easy to figure out on a MK1. If you hear the fan running so loud that it almost covers the sound of your engine it is because it’s working fine.

 

[pbfoot]

Focus cooling systems use constant flow heater cores and whoppingly better about never clogging up due to it. They flow all the time.

If the car has had tap water in it they will clog.

 

[DialM4Speed]

OK I got it all back together and ran it at 2500 for about 6 minutes. The needle stayed in the middle of the gauge and until the end of the procedure no coolant came out. The coolant erupted like a volcano after 5 minutes and I immediately shut down the engine. Topped it back up and let it run for about 15 minutes everything looks good. The wife is gonna take it to work tomorrow and we'll see. Her commute is only 3 miles and I've told her to keep an eye on it. If that didn't fix it, then it's off to the shop.

 

[pbfoot]

OK I got it all back together and ran it at 2500 for about 6 minutes. The needle stayed in the middle of the gauge and until the end of the procedure no coolant came out. The coolant erupted like a volcano after 5 minutes and I immediately shut down the engine. Topped it back up and let it run for about 15 minutes everything looks good. The wife is gonna take it to work tomorrow and we'll see. Her commute is only 3 miles and I've told her to keep an eye on it. If that didn't fix it, then it's off to the shop.

Hopefully that purged the air pocket. I got 2 years out of a leaking head gasket with Barrs stop leak head gasket sealer. It is a copper /sawdust formula. Never use Blue Devil or any polymer type gasket sealer. It was 20 bucks. Just put half a bottle in and let it idle for 20 minutes with the cap off.

 

[bcat]

Barrs stop leak head gasket sealer. It is a copper /sawdust formula. Never use Blue Devil or any polymer type

Barrs gets mixed reviews. Some good, some bad. IDK, never tried it.

I have used K-Seal though. Fixed my radiator leak without plugging anything up. Except the holes.

 

[pbfoot]

Barrs gets mixed reviews. Some good, some bad. IDK, never tried it.

I have used K-Seal though. Fixed my radiator leak without plugging anything up. Except the holes.

It only works if you can idle the car without overflowing. I gave you my review. It works.