Replaced three expansion tanks in the past six months. Small little pressure cracks - nothing spewing. Have had the system flushed, new thermostat and pressure tested, but nothing that indicated gases getting into the coolant. Any ideas or suggestions for next steps would be appreciated. I've been replacing the tank under warranty...it is the expensive one for the 2004, but wondering if I might have better luck with the cheaper one for the earlier models.

Thanks in advance.

Dave

 

Replace coolant cap also? Maybe holding too much pressure. Dexcool coolant?

 

Are you using new bottles or used?
As Buzz mentioned, also replace the coolant pressure cap.
For what it is worth, my 14 year old D2 is still on it's first bottle, not sure why you are going thru them.

 

Savannah - no, I have not replaced the cap. How would an older cap be contributing to pressure build up? I'll do it when I replace this currently leaking tank.

I am running Dexcool. I flush and refill every couple of years and have not observed any anomalies with the used fluid. How would it be effecting the internal pressure?

Thanks for your input.

Dave

 

Dexcool known for eating up caps as one thing. If a cap was holding too much pressure, then that could contribute to failure. Good thing you change yours.

 

Mike,
I'm using new.

I replaced the original one last November, as the overflow nipple cracked, and it was leaking quite a bit. I've gone through 3 since then.

I'll replace the cap, too.

I've read that I can use tanks for the older D2s - is there any difference between them structurally that would warrant the huge price difference?

Thanks,
Dave

 

Your expansion tank / bottle is blowing up as you have excess pressure in your system from blown head gasket(s).

Humans are creatures of denial.

Eventually, it will really blow up when you are driving.
The pressure will explode a hose and then you'll overheat and the engine will be done.

Or you will replace the head gaskets and live a happy happy life.

 

Coolant would leak from head gasket failure at that area before from a small void/crack in expansion tank IMO. I have had the same problem, have had 2 new replacements start leaking from the bottom of the tank in the past year. I am waiting for tank number three to arrive presently. Both tanks started leaking in the same area very near a mold line from mold tooling. I have a relatively fresh top end rebuild on my D2. I had to replace the original tank while performing that rebuild because tank was so brittle I snapped the lower nipple off while trying to install the hose. I flushed the dexcool out of the engine during top end rebuild and have run G05 in it since then. I suspect the aftermarket tanks I am using came from same manufacturer despite being marketed by different companies. Replacement and Garage-Pro are the advertised manufacturers of the two tanks I have had bad luck with. AB doesnt sell the OE part anymore that I am aware of so if you want OE you probably need to buy from your local LR dealer. An AB representative told me very recently that the tanks for 99-02 Discos are exactly the same part as the 03 and 04's. The OE parts may be slightly different but I dont know for sure. I am giving the third aftermarket tank a try since the vendor is replacing it under warranty. If it fails like the others I will bite the bullet and pay my local dealer their ransom for an OE unit. I hope we both have better luck with these parts this time.

 

I don't know if a 99-02 tank is the same as an 03-04? if I remember correctly when I replaced my there was a huge difference in price between the two.

 

There used to be a significant price difference. AB now sells both parts for the same price of $69.95 last time I checked thier site 2 days ago.