DONAIMIAN

iTrader: (18)

My mom has a 2001 Durango and latley it has been giving her some problems. Shes the only owner so its not like it has an unknown history, shes put all 115k miles on it. A couple of months back a heater valve broke or something like that, dont remember off the top of my head, but its for the heater in the back, and when it went she lost all the coolant, got that fixed. About 3 weeks ago she had an issue where it was running hot and I think it boiled over, but not sure because I live about an hour from her. She thought it was a poped radiator hose, but I just think it was just a lot of air in the system and the cap released. I topped off the system and bled it like you would an LS1 (bring it to temp with the cap off, and let the thermostat open then top off as needed, shut it off let it cool top off if needed again). Thought the problem was solved. Tonight I get a call with her saying its running hot again, and its shaking pretty bad. I wish I could give a better description, but im not there to experience this first hand. She says its comming from the motor and it dosent sound good. She compared it to the lope from the cam of my trans am. She called back again and said it wouldnt start, it would turn over, but not fire. Then later it eventually started, but still dosent sound good, and not the coolant is going cold. I have no idea whats happening, I know little about the newer Dodge motors or anything. Any help with this would be appriciated. Thanks.

MrDestinE

Any time you overheat an engine there is always a good possibility that one or both of the heads will warp or at least a weakening of the head gasket.... chances of torque to yield head bolts stretching or any combination of the above. ( this will be true of any engine no matter if aluminum or cast iron head ). I would check for water in the oil and oil in the water, do a wet and dry compression test after checking the plugs and cylinders for water. If you do not find any problems there you will just have to start checking the cooling system, Thermostat sticking? has the radiator been flow checked, has the cooling system been pressure tested? ( do this BEFORE pulling the heads or anything off... may save you a lot of time and money ) After a pressure test, verify that the coolant level has remained the same, if not where did the coolant go.. Do the diagnostic before changing parts. The cost of a pressure tester will more than pay for itself. also you may want to check all hoses, sometimes they will collapse in service and fan clutches will pass all tests but will still not cool properly ( had one drive me crazy.. I know it was a short trip! ) If there is a lot of miles on the hoses that is one thing I do not mind replacing out of general principal, belts too, I do hate replacing things not necessary...
good luck
TJ

MrDestinE

PS...
On any engine with aluminum heads you MUST change your antifreeze on a regular basis or the resulting mess in the coolant will corrode the heads from the inside to the point of eating past the head gasket... I see this every day... weakened antifreeze will accumulate acids and the water we use can have electric potential that causes electrolysis also adding to the corrosive effect....
Cadillac in their parts department sells a consumable anode that you drop into the radiator to protect their 4.1, 4.5, 4.9 engines, I cannot remember what they call it though.. instead of the block being consumed the anode was and was replaced once a year
TJ

DONAIMIAN

iTrader: (18)

Thanks for the input. Ill go over thoes things next. After the time it was blowing steam, I told her she should go get the system flushed, but I guess she never got around to that, lol.

Any clue on what would cause the poor running og the motor?
Also do the 4.7's have aluminum heads. Im clueless to this.

MrDestinE

Yes, the heads are aluminum..... if the engine runs rough as soon as it is started ( before it builds heat) it is definitely hurt.. do the compression check and the tests listed above..

TJ

DONAIMIAN

iTrader: (18)

Well she sent it to the stealership. I didnt get to talk to her much about it because I was in a rush to class, but somehow or another it was valvetrain related. Theyre replacing 1 rocker, and all 16 lifters plus some misc stuff. Ill get the full details on it later tonight.