Could it be the head gasket if the car isnt smoking?

Question

We have a '96 cadillac with a north star engine. For some reason it keeps over heating all the time. We are constantly putting antifreeze in it but it must be leaking cause it just isnt working. We took it in to the shop and they fixed the thermostate and it wasnt that because it is still doing it. The guy said it might be the head gasket but they dont fix them there. The thing is I thought if it was the head gasket it would start smoking.

I think the oil is fine we just had an oil change the other day and the over heating has been going on for a few weeks.

we can smell like a sweet smell when the engine is on. I assume it is burnt antifreez.

Answer 1

Every car can have a different cause for the same problem. Start with the easy stuff first like the reservior cap for leaking under pressure. Remember as the temp increases in the system it creates pressure which inturn raises the boiling point of the coolant.So any part of the system that flows with air/coolant can be at fault.A real technician can figure it out without changing a bunch of parts to find it. To confirm or deny the head gasket take a dry compression test. If two or more cylinders record low reading theres one problem.Restricted air flow or restriction of flow to the radiator is another problem. Also air pockets in the system can cause overheating. By the way northstar engines usually start to leak internally on the rear head. The problem with these engines the threads in the block start to go away with coolant failure (corrosion) the block will have to be rethreaded with special tools a 11mm hole block is junk if this cannot be done.There is a update to the block with threads/inserts its less expensive to replace the engine than buy the tooling.

Answer 2

You can check the antifreeze for presence of exhaust gas indicating a head gasket crack or leak. Frist look for a constant or continuous flow of large bubbles (like a pot of boiling water) which indicates compression gases are in the cooling system. These bubbles are typically larger than 1”, and bubble at a rate greater that 1 bubble every 2 seconds. No bubbles or intermittent bubbles indicates the assembly
is OK. Perform a Combustion Gas Leak Check (Block Test Kit) on the cooling system to verify “bubble test” before proceeding to pull the heads. To confirm combustion gas leaks into the cooling system, recheck the system with a fluid
type block checker (combustion leak check).

Block tester available as:
Snap-On GDCT16
Napa BK. 700-1006

1. Disconnect or clamp off the coolant reservoir hose so that the tester does not draw coolant from the reservoir.
2. With the radiator cap off, drain or siphon the fluid down to the bottom of the filler neck.
3. Start the vehicle and let it run until it reaches normal operating temperature (so that the coolant has already expanded).
4. Continue to siphon fluid down to the bottom of the filler neck while squeezing the upper and/or lower radiator hoses.
5. Add test fluid to the tester and perform the test according to instructions for your equipment.
6. Identify the color of the fluid after performing the check (BLUE or YELLOW):

If the fluid remains BLUE, the block is OKAY. If YELLOW you need to replace the head gasket and inspect for any cracks.

Answer 3

yes it could be the head gasket without smoking, see if there's any antifreeze on the oil dip stick, you can also bring it to the shop and have them check for hydrocarbons in the antifreeze reservoir sometimes you can have a leak but the antifreeze never hits the ground ,it drys up on the hot engine before hitting the ground. other possibilities are, water pump, loose belt, radiator cap

Answer 4

1. Have the cooling system pressure checked. Should hold 15 PSI with no variance.

2. Check that the rad fan is operating correctly.

3. If the coolant has never been changed, then have the radiator flushed & pressure checked. The anti corrosion additives break down in the antifreeze, then the aluminium begins to corrode plugging the tubes.

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Answer 5

Do you see an antifreeze leak? If so, get it fixed. If not check the engine oil level. If too high, coolant is going into the engine.

Answer 6

a few other things can cause it to, like maybe it needs flushed out, ok try this, once the engine is hot, shut it down and feel the radiator next to the fan and see if you feel cold spots, and if you do, the radiator needs flushed out, also you could have a hose going closed, while your driving and also it could be the water pump acting up, but if i were you, i would give it a good flushing out first, oh by the way, i almost forgot, see if the fan is kicking on.

Answer 7

Napa Block Tester

Answer 8

when a headgasket goes there many signs smoking is one of them but it can still be the head gasket . is there oil in your coolant bottle or water on your dipstick or oil cap,you can some times smell cardon in your coolant bottle.
hope this helps

Answer 9

what does your oil look like if water is getting in the oil it will be milky looking. does it run rough head gasket loosing cylinder pressure should cause it to miss.