newer cadalic, engine overheating

[chucklenut]

my friend called me, his newer caddy (has nearly 100k miles on it) started overheating and the onboard computers shut the engine down mostly then it stalled. he let it cool down, cranked it, and then the same thing happened pretty quickly. he checked under the hood and couldnt see any leaks and the reservoir was full

i told him that i would bet money it is the water pump. i know they usually go out at about 80K to 120K miles and its the only thing i could think of that would cause his engine to overheat in such a way

what yall think? ill know for sure by tomorrow when i speak to him again

 

[CBH13]

deff could be a water pump as your right they are normally changed at 100k, one thing he can check is if it heats up when its just sitting there or does it do it only when he's driving. Could also be a fan if its doing it a lot with it just sitting there cranked. I would also recommend to go ahead and do a full radiator flush first and make sure its just not just something gumming it up which is what was the problem with my buddies car, radiator was full of gunk and when it sat and idled it would be ok but when you started pushing it you'd notice the heat raise fast.

 

[chucklenut]

deff could be a water pump as your right they are normally changed at 100k, one thing he can check is if it heats up when its just sitting there or does it do it only when he's driving. Could also be a fan if its doing it a lot with it just sitting there cranked. I would also recommend to go ahead and do a full radiator flush first and make sure its just not just something gumming it up which is what was the problem with my buddies car, radiator was full of gunk and when it sat and idled it would be ok but when you started pushing it you'd notice the heat raise fast.

good point

he is letting a mechanic fix it, but ya i would replace the water pump first and then either flush the radiator or get a new one

 

[the_great_white]

i'd try the thermostat first.

 

[chucklenut]

i'd try the thermostat first.

not as familiar with this part, i have replaced my water pump so that was my first guess

 

[Lobo1]

i'd try the thermostat first.

If the thermostat sticks in the closed position it won't open at its temp range setting thus preventing no or slow water circulation in the engine. An easy test for this is to take thermostat out and out it in a pan of water. Bring water to a simmer and watch to see if it opens up. If it does, it is fine. Could be this, water pump, radiator clogged, ( no body added coolant lately and put the wrong color in did they?) could be radiator cap not releasing pressure, bottom hose sucking closed if it is weak.

 

[CBH13]

If the thermostat sticks in the closed position it won't open at its temp range setting thus preventing no or slow water circulation in the engine. An easy test for this is to take thermostat out and out it in a pan of water. Bring water to a simmer and watch to see if it opens up. If it does, it is fine. Could be this, water pump, radiator clogged, ( no body added coolant lately and put the wrong color in did they?) could be radiator cap not releasing pressure, bottom hose sucking closed if it is weak.

that wrong color is exactly what happened to my buddy. It makes a nasty concoction when you mix the two

 

[jmartinroe]

I don't know if this model has electric fans but make sure that they come on.

 

[torinodan]

( no body added coolant lately and put the wrong color in did they?)

Also, did someone drain and service the cooling and not burp the system?

 

[Lobo1]

I don't know if this model has electric fans but make sure that they come on.

Yeah an electric fan gets power through a relay so if it isn't coming on don't automatically assume the fan is bad. Pull the electrical plug at the fan if it doesn't come on and see if you got voltage at the connector. Either with a VOM ( volt ohm meter) or a 12 volt DC test light. Also check the fuse.
If it is a mechanical fan check the fan clutch. It will be bolted to the fan itself. The clutch has thermos oil in them that makes the clutch energize and de-energize as the thermos oil heats up and cools down.