How long to know if you have a cracked head in your engine?


#1

I have a 94 Cavalier. It has at least 3 cracked fuel injectors. I couldn’t reach the 4th to see if it was too. It also over heats after only driving a couple of miles. I have changed the Thermostat and the coolant level is normal. I was told before I bother replacing the fuel injectors to change the oil to make sure the head isn’t cracked. I changed the oil yesterday morning and haven’t noticed anyother fluids mixing with the oil yet. How long would it take to notice if it had a cracked head? Also, if the head isn’t cracked would a radiator flush help with the overheating problem? Thanks for any help on this. It’s been a nightmare and it’s my parents car they are letting us borrow. They live out of state and are determined to get it running normal.


#2

take the radiator cap off and see if you see the antifreeze circulating through the radiator. im not talking about driving it this way, just to observe with the hood up.

make sure you have circulating coolant.

I would also remove the thermostat from the housing. (just to remove any possible blockage from that) just remember you have to reinstall it.
so you know, it is possible to install a thermostat in backwards. then you get NO circulation.

are the radiator hoses hot, both top and bottom? make SURE you dont get caught in the cooling fan blades. is there a difference in the top hose and the bottom hose as far as temperature goes? (there should be; one has the hot water coming from the engine, the other has the [relatively] cooler return from the radiator.)

if the radiator is showing flow, and the hoses get warm (showing circulation) then you can eliminate the water pump being bad. if the hoses are showing a difference in temp, then the radiator is doing its job.


#3

Have you checked the belt that drives the water pump? It could be loose and not turning your pump fast enough to circulate the water.

To add to cappy208 reply do not remove radiator cap while engine is hot! Wait till it cools down then remove it. Fill with fluid as needed and with the cap off start your engine and let it warm up till you see the water in the radiator start to flow. It should start to flow before your cooling fans come on. If it don’t then you may have a blockage somewheres. Do your cooling fans come on when engine gets hot?


#4

If you aren’t using coolant or oil, and there is no mixing of the two, it’s not likely to be a bad headgasket (which is MUCH more likely than a cracked head).

Is the electric cooling fan operating properly? How old is the radiator, and has the coolant been changed on schedule?

It has 3 cracked fuel injectors??? That’s very odd.


#5

If the cooling fans are working, two possibilities come to mind on a car that old.

The first is a clogged radiator. Clogged could mean that there’s enough of a coating to insulate and prevent it from dissipating heat properly, even if the coolant is flowing.

The second is that the impellars in the water pump have eroded to the opint that they’re no longer moving much fluid.


#6

I agree with what has been said. The easiest way to see if there’s a cracked head is oil in the radiator and coolant in the oil. Also, you might notice some white smoke coming out the back and it would run really rough. As was said before, you’re more likely to have blown a head gasket than cracked the head and you would have noticed either of them within a day or less.

Chances are good, if you have changed the thermostat and it’s working correctly, that you have a bad water pump.


#7

Thanks for all the input. It helps a lot. I will have my husband check for all those things when he gets home tomorrow. We would take it to a mechanic to look at it, but we live too far from any to get it there before it over heats. I know he will apreciate all of your help. Hopefully he can pin point it now. He is getting tired of fixing things and having it not help.


#8

Why is it weird that there are 3 cracked fuel injectors? Just wondering if you think it could be something else. We took it to Wal-Mart to get an oil change and they wouldn’t do it because they said it had cracked fuel injectors. We called some auto parts stores and they asked how many were cracked because we would only need to replace the cracked ones. We felt and could only reach three of them and thought they felt cracked. The car has a strong gas fume that comes when we are idle. It has gotten to where I have to pump the gas pedal to get it to start. It seems like the engine isn’t getting enough fuel to start it. Anyway, if you have any other ideas I would be happy to hear them. You’ve all been pretty helpful. Thanks


#9

Fuel injectors are fairly robust. I’ve had fuel injected engines with over 200K miles without a hint of fuel injector problems.

However, since you are getting a raw gasoline smell, you could have leaky injector O-rings or fuel rail. Much more likely than cracked injectors.


#10

Ok, so I went out to check and see if the coolant was circulating through the radiator, and the coolant was empty. So I put some into the coolant compartment and then add some to the radiator directly (because my dad said to do that if the coolant container was dry) mixing it 50/50 coolant and water. Now the car wont start at all and it is spraying coolant out the exhaust. Coolant is dripping like a faucet leak from the muffler. Any ideas on why this would be happening?


#11

I’m guessing the head gasket(s) have blown, based on the coolant coming out of the muffler…but one of the real mechanics here will be able to confirm or deny that.


#12

Is there more than one head gasket?


#13

If it’s got the V6 engine, there are two, if it’s the 4 cylinder, I believe there is only one.


#14

With this problem. How big of a chance is there that a fire could start?


#15

Correct. And the HG is the most likely cause of the problem.


#16

Thanks. We’ll get that replaced this weekend.


#17

I was telling my husband all of this when he came home last night. He said he went to change the headgasket a couple of months ago and it was perfectly fine. He said in this car it is located at the top of the engine block. He is wondering if there is any way it could be a manifold gasket or some other gasket in the engine? Thanks


#18

Wow, this is really something. Please let us know what is happening and when you get it fixed.