I just replaced the water pump o-rings and the car is still leaking antifreeze. I will tear it back appart in the next several days to see what I may have done wrong. Im thinking I may have smashed the oring between the block and water pump sleeve, or it somehow came out of place when I bolted it down. Anyone performed this install before?

 

need special lube for this repair.

 

Try reassembling it using a light grease on the rings. It will prevent snagging and tearing the rings.

 

I used water based K-Y jelly with success.

 

The warming kind is the best I hear

 

Thanks for the replies. I did lube the o-rings before installation. I tore the car back appart and found that the o-ring that goes against the block seemed like it was not big enough. Meaning it did not fill the groove up entirely when the 2 bolts were tightend up. I noticed on the invoice both o-rings had the same part number and wondered if that is correct. I went to the hardware store and bought an o-ring that is a bit fatter and slightly larger in diameter than what I got from the dealer. I am going to give it a try and see what happens. I will definetly check for leaks this time before putting the car back together entirely!

 

also make sure to clean out any corrosion that's built up in the groove and on the mating surfaces that the ring seals against. Other than that, it seems you have the bases covered!

Matt

 

All my tools are special

 

Actually, this is a great idea. The KY will not attack the o-ring material like other lubes.

 

Ok guys. I put the engine back together last night, filled and bled the cooling system and let it run while I checked for leaks. I did not bolt the modular front end on so I could have a better view of the area. Sure enough after the cooling system was pressurized the drips began. Upon closer inspection it appears that the coolant is leaking from the water pump. I suspect from the weep hole. FYI - I called the Mini dealer and the new water pump is $150.

And yes the KY Jelly worked for the orings!

 

Got the new water pump on. Bled the system and no leaks. Let it idle for a long time, no leaks or over heating. So the wife drives the car today, after about 20 miles she called me and said there was a strong burnt antifreeze smell all of the sudden. I suspect from contact with the exhaust. Then of course the car overheated.

This is exactly what it did before this whole fiasco started, puked all the coolant out and over heat. What could be causing the car to blow its coolant out all the sudden like that even though the heat gauge is normal?

I am really starting to hate this car.

 

thermostat maybe??? radiator fan might not be turning on also.

sorry this is going on with the ride.

James

 

Did you check the SC drive gear when you put the new water pump in? When I lost mine, the car would idle without over heating, but shortly after getting undeway it would over heat and "puke".

 

The only things it can be are:

No coolant (you can check this)

Water pump impellor chewed up or spinning loose on shaft (probably not because you installed a new one)

Water pump not turning (reduction gears in rear of SC chewed up and not turning the pump, as stated in the last post) Do you hear any noises from the rear of the SC?

Lot of air in the system (did you bleed it?)

T-stat no opening (low on the totem pole, but must be checked at some time)

Electric fan not coming on (bad fan or bad fan t-stat or blow fuse or other electrical reasons)

Clogged up radiator

Extremely retarded ignition timing (probably not)

Most of these you have fixed or they have been recommended to be looked at by others on this thread.

Check them all, one of them will be the culprit. Don't assume any of the above is OK unless you have personally confirmed.

Does it overheat if you maintain a good cruising speed with good airflow into the radiator? If it does not overheat, then it is probably not the SC drive gears.

Does it only overheat when stopped in traffic or sitting in the driveway. If it only overheats here, then I would suspect the electric fan, motor, fuses, wiring, and fan stat.

This will give you something more to do tonight when you get home. good luck

And you say even when it boils over, the temp gauge still does not move? I've heard many complaints about the gauge... wonder why they even bothered to add one if it is so dampened it is worthless?

YD

 

Thanks for all the tips and I will follow through with the ones I haven't tried yet.

While driving the car is fine, when you stop is when it starts pushing coolant out from under the cap on the tank.

So last night I re-filled and re-bleed the system. I spent about 45 minutes and appeared to have a better result than the first time. Tank was full and coolant coming out both bleeders.

I drove the car about 20 miles. I stopped 3 times and smelt a hint of coolant each time. When I got home I smelt coolant, so I quickly opened the hood to see what was going on. It was forcing coolant out from under the cap on the coolant tank. Luckily I had a screw driver in my back pocket so I loosened the front bleeder screw and a LOT of air pushed out (consequently stopping the coolant forcing out the cap). After all the air seemed to come out I tightened the bleeder and let the car idle for about 10 minutes with the A/C on. The cooling fan was kicking on and off (also newly replaced!), but the car never got hot or lost any coolant. I once again loosened the front bleeder and no air came out this time. I took the bleeder screw all the way out and could see coolant rushing by, something I hadn't seen before (as opposed to just seeing coolant set in the hose).

As of right now the only thing I have not checked is the thermostat. As far as I have had the car apart you'd think I would know the location of it, but I don't. Is it on the end of the head?

Again, thanks for everyone's thoughts.

And yes - the temp gauge - apparently useless...

 

I experienced something similar, but in a Saab. I noticed you didn't mention the actual reservoir cap itself on its tank. It could be faulty and should not be that expensive to replace (or maybe borrow one from a fellow MINI). My cap was replaced when coolant began spraying mist (high-pressure washer style) at a traffic light. From my understanding, they are suppose to hold pressure up to its pressure relief limit and then open up....I think mines opened too soon.

The thermostat you mentioned is also a good suspect. My previous Saab had a problem with that too around the same time as the reservoir cap incident...but the symptom was low temp reading on the temp gauge for extended periods.

Best of luck.

 

I took the thermostat out over the weekend and picked up a new one. Just for curiosity I did a simple test. I dropped both thermostats in a small pot of water and set the burner to high. I watched closely and sure enough both opened at the same time, just before the water reached a good boil.

I have not reinstalled the thermostat yet, but I am thinking this is a bigger problem. One way or another something is pressurizing the coolant system beyond its normal limits. Head gasket, warped head or heat exchanger? No milky substance in the coolant tank, so I doubt its the heat exchange I've read about. I guess I'll do a leak down and see if the gasket/head is good.

I guess the coolant cap could be faulty and releasing pressure to soon, but is it normal for the tank to be completely filled with coolant at any point anyway??

Am glad this is a 3rd car and we don't depend on it. Haven't been able to drive it for over a month.

 

[quote=chawness;1579965]
I guess the coolant cap could be faulty and releasing pressure to soon, but is it normal for the tank to be completely filled with coolant at any point anyway??quote]

The tank should not be filled all the way....when cold it should level off about 1", 2" at most from the bottom of the tank.
When Hot, the coolant level rises to about the middle of the tank.

Has the tank been filled up all the way during the previous tests?

 

...also, does the radiator fan come on without the AC being activated?
You said it never overheated during the time the AC fan was on right?

 

[quote=sfjames2;1580025]It has been filled to the "max" mark...

 

Yes fan is working with AC on...

 

Well I have not posted my final result for fear of jinxing what seems to be a solved issue. But we have driven the car over 150 miles so maybe it is safe now.

I installed the new Thermostat and re-bleed the system and so far so good. Although the old T-Stat tested ok, perhaps it was sticking when it was in the car? When I re-bleed the system I had coolant gushing out of both bleeders this time, so I figured there was little or no air left in the system.

Solution = Thermostat

Again thanks for everyones input