Last post on Sep 23, 2013 at 3:55 PM
You are in the Dodge Dakota-2010 and older
What is this discussion about?
Dodge Dakota, Truck
#73 of 261 Re: Dodge Dakota 2002 Overheating [tommy63]
Sep 18, 2007 (5:57 pm)
Not with a functioning cooling system.
You did not say which engine you have... if it is the 4.7L Semi-Hemi, make CERTAIN you used the proper bypass thermostat. The wrong one may fit but will not work correctly.
Also, you may wish to do a leakdown test to make sure the cooling system is not leaking internally. (inside the enigne) Are you noticing any antifreeze loss?
Also, dont forget that the waterpump on the 4.7L Semi-Hemi spins the OPPOSITE way of other engines... the routing of the belt is important! (it is possible to route belt wrong way so waterpump spins backwards)
#74 of 261 Re: Dodge Dakota 2002 Overheating [bpeebles]
Sep 18, 2007 (6:22 pm)
It's a 4.7L. There is no coolant loss. I have belt on according to diagram under hood. One thing I have noticed is one side of radiator is hot (right side) while left is cool, that is while I'm standing facing truck. As for the thermostat, it's a 195 degree same as the one I took out, but did not buy it at Dodge Dealer. The spring on thermostat is in engine so to speak. Also my wife pulled our 24' Travel Trailer up here to Wyoming from La with the truck, but ever since then it has been overheating, so I made the changes but that did not help. Thanx
#75 of 261 Re: air conditiong controls not working properly?? [kschlichting]
Sep 19, 2007 (11:51 am)
Sounds like a vacuum problem. Do you notice the air also going to the floor even when set on dash when you go from a steady speed to accelerating? If so it could be a broken vacuum line under the hood or the vacuum motor that moves the door for the dash air.
#76 of 261 Re: Dodge Dakota 2002 Overheating [tommy63]
Sep 20, 2007 (5:39 pm)
The fact that you noted that one side of the radiator is signigicantly cooler than the other side points to a problmem with lack of coolant FLOW.
Do not forget that the 4.7L semi-hemi uses a BYPASS cooling system. This is noted by the fact that the thermostat is mounted LOW on the engine (not at the top of it) This type of cooling system ALWAYS flows coolant thru the engine past the thermostat. One end of the thermostat 'senses' the temparture of this engine flow and the other end of it 'throttles' the flow of coolant out of the radiator and precesicely mixes it into the hot engine coolant. This is why using a 'normal' thermostat will really mess up the cooling system because it does not have the ability to perform this function.
Here are a couple of other things to think about;
Does the heater put out heat?
Did you "burp" the air out of the cooling system using the special valve at the high point of the cooling system? (above power-steering resivour on radiator plumbing)
BTW (for future reference): It is worldwide standard to speak of "right" and "left" side of a vehicle based on the point of view from sitting in the drivers seat. (not standing in front of it facing it)
For example: The right headlight is the one on the PASSENGERS side.
#77 of 261 Re: Dodge Dakota 2002 Overheating [bpeebles]
Sep 20, 2007 (8:10 pm)
I wanted to let you know that through your advice my truck is now back on the road. I did the burp thing as you advised, put an identical thermostat in truck to the one I took out, and all is well with my Dakota. Sir, I appreciate all the advice/help you gave in getting my truck fixed. THANK YOU SO VERY MUCH. I do have one more question. Why is the 4.7L called a semi hemi?
#78 of 261 Why is the 4.7L called a semi hemi? [tommy63]
Sep 21, 2007 (5:06 pm)
That is an easy to answer question...
First of all, lets review why an engine would be called a "Hemi" in the first place. The term "Hemi" is slang for "Hemisperical". In a piston engine, the area from the top of the piston to the top of the cylinder head by the valve heads is known as the combustion chamber (this is actually just an area of air!). The combustion chamber on most overhead valved AUTOMOTIVE engines are either wedge shaped (think of a piece of pie) or hemispherical (think of tennis ball cut in half). The cylinder head design dictates the combustion area shape, so when someone says "hemi", it really only refers to the engine's cylinder head having a hemispherically shaped combustion chamber.
Hemi heads have the spark plug located at dead center of the combustion chamber, which makes for an extremely efficient & powerful fuel/air mixing & flame burn (actual igniting of the fuel/air). Hemi heads also have ideal valve placement to help the flow of air (intake & exhaust) through the cylinder head. In simple terms, the head design is VERY efficient, and allows an engine to make excellent power! On the downside, hemi heads themselves usually are quite heavy & large, and valvetrains can be somewhat complex (read: expensive).
The 4.7L engine is a "semi Hemi" because the head is almost a perfect sphere... except for a small bump.
Here are some links which further describe the 4.7L semi-hemi
#79 of 261 Re: Why is the 4.7L called a semi hemi? [bpeebles]
Sep 22, 2007 (8:23 pm)
Thanx for the explanation on the engine. My wife said to tell you Thanx very much for the help in getting our truck fixed. Again, Thank You.
#80 of 261 Re: Why is the 4.7L called a semi hemi? [tommy63]
Sep 24, 2007 (2:51 pm)
As an aside to Bpeebles excellent explanation, when Chrysler first developed the "semi-hemi" combustion chamber in the 1950s, they were referred to as polyspherical engines, meaning they used a combination of wedge and hemispherical designs.
#81 of 261 blower motor switch
Dec 07, 2007 (7:33 pm)
94 dakota 318 w/air 2wd
short story... blower motor worked only on high. then it didn't work at all. the way it happened i'm pretty sure it is the speed control. checked resistance on it but without documentation for the terminals....
help me please!!!!
#82 of 261 Re: blower motor switch [magnummark]
Dec 08, 2007 (5:29 pm)
It's your fuse relays. My blower wouldn't even work. Mine was on the outside firewall in the engine compartment on the passenger side.
I hope that helps.