Replaced timing belt and head gasket now car gets hot

pontiac
sunbird

#1

I have replaced the timing chain and head gasket (yes, I had the head inspected). The gauge indicates that the car is hot (it never got hot before the head gasket blew). I replaced the coolant temperature switch, the fan quite running, dash gauge stayed on cool. put in the old switch, gauge reads hot quickly, but takes the car a few miles to catch up. Any advise?


#2

You need to test for the presence of hydracarbons in the coolant. What I mean is exhaust gasses are comming in contact with your coolant.


#3

Thank you for the advise. Could you suggest how to test? I have no clue. Really am learning as I go.


#4

Test kits are available at the auto parts store,easier than baking a cake.


#5

I’ll give it a shot and see what happens. Could the O2 sensor be bad?


#6

The idea behind checking for hydrocarbons is to see how the head gasket is holding up. If there are hydrocarbons present, exhaust gases are getting into the coolant, which in turn means the head gasket is not sealing properly. That, in turn, means it will need to be redone. Hopefully that’s not the case, but it’s gotta be checked.


#7

And by exhaust gasses, he means HOT gassaes are being blown into the water jacket from combustion, perhaps a few thousand degrees. That’ll heat the coolant up real good.

One thing I wanted to add is that if a test kit shows no presence of hydrocarbons in the coolant and a pressure leakdown test show no headgasket breech, it’s also possible that there was an installation error. You wouldn’t be the first person to make one and inadvertantly block cooling passages.


#8

I would test for hydrocarbons first, but I would not rule out the possibility that the thermostat is bad. Could you tell us exactly what the gauge is showing and what other factors leads you to believe the engine really is overheating.


#9

Did you install new head bolts? The head bolts are torque-to-yield type head bolts on this engine, which means that they can’t be reused when installing the head.

Torque-to-yield type head bolts stretch when they’re torqued down. Once they take a stretch, and you try to reuse them, they don’t provide enough clamping force to create a seal between the head an block at the head gasket.

Tester


#10

It’s a little hard to tell from your description, and the head gasket is certainly the prime suspect. But don’t entirely overlook the possibility that the thermostat or water pump has picked this unfortunate time to malfunction.


#11

Installed all new bolts, water pump thermostat, radiator cap, and gaskets, oil filter, oil pan seal - everything but the kitchen sink. Going by the instructions in the manual, went back and retorqued the bolts after the engine got warm. I watched the gauges after starting the car, that is when I first saw that the temp gauge showed hot, but I could still put my hand on the radiator hoses and radiator cap, but no heat like the gauge was indicating. It’s just frustrating. I’m still thrilled that the car started. It doesn’t smoke either.


#12

Well he said he replaced the water pump and thermostat, so surely they are ok. He said that when he changed the temp sensor the fan quit. I wonder if he waited until the engine heated up to decide the switch was faulty. It sounds to like the old temp switch is the problem.


#13

Okay. How did you measure the last 60 degree three step sequence for the final torque?

Tester


#14

If your timing chain is off by one link { retarded ] the car will overheat,start easily and be down on power.


#15

As I said earlier, I bet your old temp sender is bad.