Vapor Lock/Thermostat

[Scarlet Fox]

Hey everyone!
Here's the deal. My '94 Explorer did not start for me when I was leaving for work. I thought it was odd that the battery would be dead because it was replaced exactly a month ago. Well, the battery works fine. I was experiencing vapor lock because it's so freegin' hot out(it's currently about 100 degrees at 6:40..plus humidity lol)! I finally got it started..but I read something that you should also check the thermostat too just to make sure the engine is getting cooled like it should.

My thermostat never reads that it overheats and the explorer acts fine. My only concern is the needle for the thermostat is never right in the middle. It more or less sits closer to the Cold side (at about a 40-45 degree angle). Anybody think I should replace it anyway? Are thermostats known to go out in Explorers at all?

Thanks all!

 

[aldive]

How old is the T stat in question?

 

[shamaal]

To answer the question yes the thermostats do go bad, they usually stick though and cause the engine to run hot or even overheat. If the gauge is sitting in the same place it always does you are fine, if it's erratic the thermostat is the first culprit.

If, as Al is about to suggest, you don't know when it was changed or it's been a number of years, then it won't hurt next time you're putzing around under the hood; do the radiator cap also. I have a 91, the needle is at 30 deg, barely into operating. The thermostats from the dealer appear to be cooler than the aftermarkets, perhaps it a regional thing. I can't say that it will assist in any matter with a starting problem though.

I do not readily make the connection between thermostat and failure to start. Vapor lock is when the fuel in the system turns into a gas in the heat, occasionally it is a problem if winter gas blends are being sold or a fuel line has been routed to close to the engine. It sounds like the engine turns over so you have eliminated the battery. That narrows it down to spark or fuel. You can check the pressure at the rail with a cheap gauge from an autostore and the spark can be tested many ways, I like a test prod also available from an autostore. Use caution if you have fuel vapor floating through the compartment from a fuel rail test.

After that the exotics set in, a search on hot starting problems will provide fertile ground to plough through. The engine coolant temperature (ECT) is a common problem.

Good Luck!

 

[Scarlet Fox]

How old is the T stat in question?

I'm guessing it's the original one..sooo it's probably 13 years old! lol

 

[Scarlet Fox]

To answer the question yes the thermostats do go bad, they usually stick though and cause the engine to run hot or even overheat. If the gauge is sitting in the same place it always does you are fine, if it's erratic the thermostat is the first culprit.

If, as Al is about to suggest, you don't know when it was changed or it's been a number of years, then it won't hurt next time you're putzing around under the hood; do the radiator cap also. I have a 91, the needle is at 30 deg, barely into operating. The thermostats from the dealer appear to be cooler than the aftermarkets, perhaps it a regional thing. I can't say that it will assist in any matter with a starting problem though.

I do not readily make the connection between thermostat and failure to start. Vapor lock is when the fuel in the system turns into a gas in the heat, occasionally it is a problem if winter gas blends are being sold or a fuel line has been routed to close to the engine. It sounds like the engine turns over so you have eliminated the battery. That narrows it down to spark or fuel. You can check the pressure at the rail with a cheap gauge from an autostore and the spark can be tested many ways, I like a test prod also available from an autostore. Use caution if you have fuel vapor floating through the compartment from a fuel rail test.

After that the exotics set in, a search on hot starting problems will provide fertile ground to plough through. The engine coolant temperature (ECT) is a common problem.

Good Luck!

OKay, thanks for the advice

 

[aldive]

I'm guessing it's the original one..sooo it's probably 13 years old! lol

That being the case, swap it out.

Good luck ....