wtf is wrong with my cooling system?

[Hoot]

i need a little diagnostic help with what is going on with my cooling system. i have a 1996 disco SE. let me tell you the progression of what has and is happening: (sorry for the long ass post)

first issue: my expansion tank seem split out causing coolant to leek out of my system and hence ruin the integrety of the pressurized system. i changed the expansion tank and refilled the system with coolant.

second issue: shortly there after the rover over heated into the red on the way home. granted it was an unseasonably hot day ( high 80s) as i live in the san francisco east bay area where it rarely moves out of the low to mid 70's. i also had just gotten out of stop and go traffic and i live up in the hills so it is a pretty steep 2 mile drive in. so it was definatley pushing her.

so after i get it in the driverway it occurs to me that i am an idiot and that when i refilled the coolant i used straight coolant and did not mix it with distilled water. so i drained the radiator and refilled it with 50/50 mix and left the bleeder off of the radiator and ran it up to operating temp and got all the air bubble out.

so i thought i was in good shape. i drive it around a week or so and no issues.

third issue. on the way home form the store i was again drving up the afore mentioned steep grade home and my wife asks me, "how's Landy doing with the over heating?" i looked down at the temp gause and she was sitting in the middle right where she should be and i shit you not it instantly began to rise fast. so i turned on the heat full blast and got my ass home.

so i am figuring i need a new radiator i didnt have the time to much with it and since i am taking publice transportation to work lately i figure i will get to it next weekend.


fourth issue: so today it was not so hot out and i needed to make a trip to the store so i figured i'd drive the landy and be cautious. i watched the heat gauge almost as much as a watched the road ahead of me the whole trip there and back. again this time on the way home driving up said hill it did not over heat but i had the air vent on running in the recycle air mode, and i began to smell the tell tale "sweet smell" of coolant wafting through the vent.

the second i pulled into my drive way the smoke began billowing from the hood. a quick hood pop and i can clearly see that the top hose heading into my heater core has burst. I know these are the original hoses and that they are living on borrowed time. i have already replaced (last year) the main top radiator hose and the main bottom radiator hose. when i repaced them i put in a new thermostat and a new temp sender unit.

so now the question is what is wrong? why is the rover still overheating? is it just that the hoses and the expansion tank are all reaching the end of their lives together or do i have some sort of pressure build up issue? so what would cause that? bad radiator? bad water pump? how to i isolate the main problem? any help is greatly appreciated.

i am dirt poor right now and will definatley have to do the work myself or i will have to leave her parked until i find a new job.

 

[deiaggie]

did you replace your header hoses yet? It seems like your cooling system has not been maintained very well and alot of weak links have popped all around the same time. The expansion tanks are known to crack and hoses that are old are known to burst...what is the problem here?

 

[Hoot]

my problem is that even after replacing the expansion tank the truck still overheated. what is causing the overheating?

 

[Levi]

I had a similar problem with my camaro and the radiator was clogged up.
First off make sure your fan is running. Next I would check to make sure your coolant is flowing. In my other vehicles I just take off the radiator cap, but I'm sure you aren't supposed to take out the plastic plug on the rovers, maybe just the expansion tank cap. If you don't have flow look at the water pump or for a clogged radiator.
It seems to me if you are building up the pressure to burst hoses and tanks you aren't getting any circulation.

 

[Barnstormer]

One possible idea is a blown head gasket. I had an older Isuzu Trooper for a while that did the same kind of things- all from too much pressure in the cooling system. I finally figured out it was a head gasket that had failed between a cylinder and a water passage. The cylinder pressure would leak into the cooling system, pressurizing it to the point of blowing the weakest point in the system.
Might want to check it out.
Brian

 

[nosivad_bor]

yeah, especially considering that you got it hot and then drove it some. that isnt a good thing with these trucks.

but replace the hose and take the truck to a radiatorshop and have it "rodded out"

also check the fan, after you drive it around and get it up to temp , you can turn the car off and try to spin the fan b hand it shouldn't spin really more than a blade or two.

http://www.masterautotech.com/q&a files/download 09 16 2003 rod radiators.htm

 

[deiaggie]

my problem is that even after replacing the expansion tank the truck still overheated. what is causing the overheating?

you didnt state if you replaced the hose. I am still not seeing a problem other than the hose burst and the tank failed which is a common thing.

replace the hose and see what happens.

 

[TobyS]

You can also simply drive without a thermostat all together to make sure that is not the problem. It only helps you build heat quicker for winter time. Free flow in the summer is no problem as long as the seal still remains.

 

[Darren M.]

i need a little diagnostic help with what is going on with my cooling system. i have a 1996 disco SE. let me tell you the progression of what has and is happening: (sorry for the long ass post)

first issue: my expansion tank seem split out causing coolant to leek out of my system and hence ruin the integrety of the pressurized system. i changed the expansion tank and refilled the system with coolant.

second issue: shortly there after the rover over heated into the red on the way home. granted it was an unseasonably hot day ( high 80s) as i live in the san francisco east bay area where it rarely moves out of the low to mid 70's. i also had just gotten out of stop and go traffic and i live up in the hills so it is a pretty steep 2 mile drive in. so it was definatley pushing her.

so after i get it in the driverway it occurs to me that i am an idiot and that when i refilled the coolant i used straight coolant and did not mix it with distilled water. so i drained the radiator and refilled it with 50/50 mix and left the bleeder off of the radiator and ran it up to operating temp and got all the air bubble out.

so i thought i was in good shape. i drive it around a week or so and no issues.

third issue. on the way home form the store i was again drving up the afore mentioned steep grade home and my wife asks me, "how's Landy doing with the over heating?" i looked down at the temp gause and she was sitting in the middle right where she should be and i shit you not it instantly began to rise fast. so i turned on the heat full blast and got my ass home.

so i am figuring i need a new radiator i didnt have the time to much with it and since i am taking publice transportation to work lately i figure i will get to it next weekend.


fourth issue: so today it was not so hot out and i needed to make a trip to the store so i figured i'd drive the landy and be cautious. i watched the heat gauge almost as much as a watched the road ahead of me the whole trip there and back. again this time on the way home driving up said hill it did not over heat but i had the air vent on running in the recycle air mode, and i began to smell the tell tale "sweet smell" of coolant wafting through the vent.

the second i pulled into my drive way the smoke began billowing from the hood. a quick hood pop and i can clearly see that the top hose heading into my heater core has burst. I know these are the original hoses and that they are living on borrowed time. i have already replaced (last year) the main top radiator hose and the main bottom radiator hose. when i repaced them i put in a new thermostat and a new temp sender unit.

so now the question is what is wrong? why is the rover still overheating? is it just that the hoses and the expansion tank are all reaching the end of their lives together or do i have some sort of pressure build up issue? so what would cause that? bad radiator? bad water pump? how to i isolate the main problem? any help is greatly appreciated.

i am dirt poor right now and will definatley have to do the work myself or i will have to leave her parked until i find a new job.

I'm in the same boat. Replaced my fan clutch, hoses and had the radiator flushed. After all that, it overheated worse than it did before I took it to the shop. It's back in today to have the raditor rodded out. I had a slight core leak and put some stop leak in. Big mistake. Gummed up everything. The raditor is most likely clogged. Get that checked first.