Overheating

Ethan Keirn

Ethan Keirn

Member
May 11, 2017
57
0
6
Tidewater Virginia
#1
Ive got a 1998 GT, my intake manifold has failed for the second time, and when i replaced it the other day i started it up only to find it was overheating, and the coolant temp gauge was not working, sure enough, there is a small crack on the aluminum coolant crossover on the front of the manifold, is this enough to cause the coolant temp sensor to not work correctly and make the engine overheat? It is a very slight hole, it only loses a small amount of coolant so its not like its dumping all the coolant on the ground when i start it, could it just be throwing off the pressure of the cooling system or something??? Whats the deal?
 

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#2
To your original question. No. I don't think that a small leak in of itself will CAUSE the motor to over heat. IMO you should:
  • CONFIRM that the motor is actually over heating. MEASURE the temperature of the T-stat housing with a scanning infrared thermometer
  • There's something else wrong.
I have helped more than one person that "thought" their motor was over heating. Ignoring my advice they instead replaced a TON of parts and did a TON of work only to find it was an electrical problem "causing" the gauge to read incorrectly all along.

Regarding the leak in the intake manifold. Is it confirmed there is a crack or does it just LEAK?

The reason that I ask is IF it just leaks there are replaceable seals between the plastic and the metal cross over. These are often overlooked when doing this job. Note, I was successfully able to repair a manifold with some plastic seal damage by using RTV and new cross over seals.

>>0:53

View: https://www.youtube.com/watch?v=T9DMZ73e7zg

>>1:35

View: https://www.youtube.com/watch?v=GPoxDxktrVI

>>Double check before ordering. But this is what they look like.
Amazon product ASIN B000Q0VTX6View: https://www.amazon.com/Fel-Pro-Es71213-Water-Crossover-Mounting/dp/B000Q0VTX6

Thread with some more information:
http://www.allfordmustangs.com/forums/4-6l-tech/1010297-npi-4-6-coolant-leak.html


Fel-Pro 35958 35957

Note, the interchange data base will say this part does NOT fit but it does.
http://www.autozone.com/cooling-hea...mostat-gasket/464070_0?CJPID=4145469&cmpid=cj
 
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#4
On my 04 the intake failed where the plastic meets the aluminum, it leaked coolant out onto the coil boot and into the engine valley, but a small leak is not enough to cause it to overheat, certainly not right away anyways. I ended up taking my thermostat out and filling the area up with jb weld where the plastic deteriorated and left thermostat out so it wouldn't build up pressure there.
But I am putting cams in, in a few weeks so I'm replacing the intake with another ford one and pulling the heads to put fresh gaskets in and valve springs.

Good thing these engines are super easy to work on because you have seem to have bad luck with the intakes cracking! You should put a pi intake on, I hear there not as crappy, "as" being the key word!
 
#5
Nemethjames1 said:
On my 04 the intake failed where the plastic meets the aluminum, it leaked coolant out onto the coil boot and into the engine valley, but a small leak is not enough to cause it to overheat, certainly not right away anyways. I ended up taking my thermostat out and filling the area up with jb weld where the plastic deteriorated and left thermostat out so it wouldn't build up pressure there.
But I am putting cams in, in a few weeks so I'm replacing the intake with another ford one and pulling the heads to put fresh gaskets in and valve springs.

Good thing these engines are super easy to work on because you have seem to have bad luck with the intakes cracking! You should put a pi intake on, I hear there not as crappy, "as" being the key word!
Click to expand...
Honestly im just so tired with the BS of this car, i think whenever i fix whatever is wrong with it, im just gonna sell it
 
#6
Ethan Keirn said:
Honestly im just so tired with the BS of this car, i think whenever i fix whatever is wrong with it, im just gonna sell it
Click to expand...
Perhaps there's more going on here than just a problem that's the car's fault. At the risk of sounding rude remember:
  • You are using salvage yard parts. Tons of us do this to save $$. But there's always additional risk with used parts. There just are some parts that are riskier than others to go the salvage yard route. I personally would NOT use a salvage yard intake. WHY? Because there is a high likely hood the replacement part will have the same problem as the original.
  • You did have the intake in your hands and did have an opportunity to fully inspect the part BEFORE it was installed.
  • Seems to me that IF a new intake was installed the first time, the out come would have been different.
  • Did you REALLY do a through trouble shooting before replacing the intake manifold? Seems to me that something was missed.
Consider the "user mod" for your car. The "user mod" is an update that you get by looking in the mirror. Consider this a learning experience because it really is possible to save tons of $$ working on your own cars. But no one is born knowing how to do it. Everyone had to LEARN how to be successful. Don't give up.

Note, I have put (4) intake manifolds on various Ford products. Each time I explored using a salvage yard part. Each time when inspected the part was not much (if any) better than the part I had. Further it just seemed to me there wasn't enough money savings to justify the risk.

If $$'s are tight consider the Dorman intake. I know people have a love/hate relationship with the Dorman replacement intake. But I have one right now on my DD. Guess what? It starts when I turn the key. It doesn't leak. And most importantly, it gets my A$$ down the road and back.

Sample source for Dorman:
http://www.rockauto.com/en/moreinfo.php?pk=426358&cc=1304480&jsn=519
 
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#9
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#11
wmburns said:
Perhaps there's more going on here than just a problem that's the car's fault. At the risk of sounding rude remember:
  • You are using salvage yard parts. Tons of us do this to save $$. But there's always additional risk with used parts. There just are some parts that are riskier than others to go the salvage yard route. I personally would NOT use a salvage yard intake. WHY? Because there is a high likely hood the replacement part will have the same problem as the original.
  • You did have the intake in your hands and did have an opportunity to fully inspect the part BEFORE it was installed.
  • Seems to me that IF a new intake was installed the first time, the out come would have been different.
  • Did you REALLY do a through trouble shooting before replacing the intake manifold? Seems to me that something was missed.
Consider the "user mod" for your car. The "user mod" is an update that you get by looking in the mirror. Consider this a learning experience because it really is possible to save tons of $$ working on your own cars. But no one is born knowing how to do it. Everyone had to LEARN how to be successful. Don't give up.

Note, I have put (4) intake manifolds on various Ford products. Each time I explored using a salvage yard part. Each time when inspected the part was not much (if any) better than the part I had. Further it just seemed to me there wasn't enough money savings to justify the risk.

If $$'s are tight consider the Dorman intake. I know people have a love/hate relationship with the Dorman replacement intake. But I have one right now on my DD. Guess what? It starts when I turn the key. It doesn't leak. And most importantly, it gets my A$$ down the road and back.

Sample source for Dorman:
http://www.rockauto.com/en/moreinfo.php?pk=426358&cc=1304480&jsn=519
Click to expand...



I almost got a dorman replacement since there stronger. After learning that they TAKE AWAY horsepower I instantly stopped considering it. Something like 17hp less with just the intake?? Crazy they would sell ones for performance cars to make less performance...
 
#13
Nemethjames1 said:
I almost got a dorman replacement since there stronger. After learning that they TAKE AWAY horsepower I instantly stopped considering it. Something like 17hp less with just the intake?? Crazy they would sell ones for performance cars to make less performance...
Click to expand...
They shouldve made the entire manifold out of aluminum right from the factory, that would have prevented literally all of my problems and many other peoples problems, like i said im over this BS im just selling the car once i fix the problems and maybe ill buy a fox body or something, atleast when it breaks the parts to fix it will be cheaper
 
#14
robertsa said:
Did you check for codes yet?
Click to expand...
Yes i have checked for codes, there are none, however i was scared that i damaged the engine so no codes is kind of a good thing for me, my best guess is there is something clogging he cooling system or a bad water pump, i made the mistake of popping the water pump pully with a hammer, so i may have ruptured the seal, live and learn i guess
 
#15
wmburns said:
Do you have a Windows laptop?

Do you have $30?

If so consider ForScan. It's a game changer for accessing ODB2 operational data. The graphing capabilities are amazing.

ForScan ODB2 scanner w ELM327 USB

OHP Ford ELMconfig USB device 500kbit/s ELM327 compatible interface with MS-CAN switch for Forscan
Amazon product ASIN B01F0GVBWYView: https://www.amazon.com/gp/product/B01F0GVBWY/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A3HT224M59LA1C


ForScan:
www.ForScan.org
Click to expand...
What does it do exactly? Im up for trying anything that could remedy this problem
 
#16
Ethan Keirn said:
when i start the car cold it runs ok but once it warms up it starts to miss what could cause this?
Click to expand...
Please go back and re-read post #2. What has been done to monitor battery voltage while this problem is happening? IF you don't do any other tests do this one. Why?

Consider the possibility that the alternator is not keeping up with the electrical load. Such that when the electrical load is large, the system voltage drops. The reason why is not important right now. But it is possible to have low system voltage and the alternator itself tests perfect.

IF the system voltage drops what could happen? Misfires and the temperature gauge will read higher.

Why does low system voltage CAUSE misfires? Do you really need an to have that explained?

Why does low system voltage CAUSE the dash gauge to read high? Because the temperature sensor is basically a device that changes it's resistance based upon temperature. The ECT is calibrated to operate at a specific voltage. When the voltage is lower than calibrated the gauge will read high because the dash gauge can't tell the difference between low voltage caused by high temperature or low system voltage.

Here's where we might tie everything together. What happens when a motor gets hot?..........Well among other things. the cooling fan turns on.

What's so special about the cooling fan? How about a LARGE electrical load?

What happens when a large electrical load turns on (in this case)? System voltage drops............

Does this "theory" match your symptoms? I don't know if this is your problem but based upon my experience I KNOW it's possible.

What else could "cause" your symptoms? The list is fairly long and I'm sure that when you find the reason it will all make sense. But it may take some work and tests to get there. But it's pointless to list them if you haven't done the basic voltage tests.

Remember. There is no elevator to success. You have to take the steps!

Regarding your question about ForScan. It's basically a full function ODB2 scanner that works on Fords only. It has full data logging capabilities. There's a possibility that any ODB2 scanner could also make short work of your problem. But don't go the ForScan/ODB2 route without first making sure that the battery and charging system is in tip top shape.

Bottom line. Today's cars simply will NOT run right without a strong battery and alternator. Cut corners here at your own risk.
 
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Reactions: 1 user
#17
wmburns said:
Do you have a Windows laptop?

Do you have $30?

If so consider ForScan. It's a game changer for accessing ODB2 operational data. The graphing capabilities are amazing.

ForScan ODB2 scanner w ELM327 USB

OHP Ford ELMconfig USB device 500kbit/s ELM327 compatible interface with MS-CAN switch for Forscan
Amazon product ASIN B01F0GVBWYView: https://www.amazon.com/gp/product/B01F0GVBWY/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A3HT224M59LA1C


ForScan:
www.ForScan.org
Click to expand...
What does it do exactly? Im up for trying anything that could remedy this problem
wmburns said:
Please go back and re-read post #2. What has been done to monitor battery voltage while this problem is happening? IF you don't do any other tests do this one. Why?

Consider the possibility that the alternator is not keeping up with the electrical load. Such that when the electrical load is large, the system voltage drops. The reason why is not important right now. But it is possible to have low system voltage and the alternator itself tests perfect.

IF the system voltage drops what could happen? Misfires and the temperature gauge will read higher.

Why does low system voltage CAUSE misfires? Do you really need an to have that explained?

Why does low system voltage CAUSE the dash gauge to read high? Because the temperature sensor is basically a device that changes it's resistance based upon temperature. The ECT is calibrated to operate at a specific voltage. When the voltage is lower than calibrated the gauge will read high because the dash gauge can't tell the difference between low voltage caused by high temperature or low system voltage.

Here's where we might tie everything together. What happens when a motor gets hot?..........Well among other things. the cooling fan turns on.

What's so special about the cooling fan? How about a LARGE electrical load?

What happens when a large electrical load turns on (in this case)? System voltage drops............

Does this "theory" match your symptoms? I don't know if this is your problem but based upon my experience I KNOW it's possible.

What else could "cause" your symptoms? The list is fairly long and I'm sure that when you find the reason it will all make sense. But it may take some work and tests to get there. But it's pointless to list them if you haven't done the basic voltage tests.

Remember. There is no elevator to success. You have to take the steps!

Regarding your question about ForScan. It's basically a full function ODB2 scanner that works on Fords only. It has full data logging capabilities. There's a possibility that any ODB2 scanner could also make short work of your problem. But don't go the ForScan/ODB2 route without first making sure that the battery and charging system is in tip top shape.

Bottom line. Today's cars simply will NOT run right without a strong battery and alternator. Cut corners here at your own risk.
Click to expand...
forgive me as i am young and new to working on vehicles (i have some experience but not a ton of it my dad whom is pretty knowledgeable helps me a lot) but how would i go about testing the voltage of the system? I have a spare alternator i could hook up in case the alternator is to blame. The battery light on the dash is not on though so idk if that would be the issue but i will look into it thanks for the help
 
#18
Do you have a Volt-Ohm Meter (VOM)? If not, don't buy any other parts/tools until you have one. IMO it's not really possible to work on today's electronic cars without a VOM in the tool box. It doesn't have to be an expensive one but it does need to be accurate since you will be measuring small voltage changes.

Measuring battery voltage is as simple as attaching the VOM at the battery.

Monitoring voltage inside a moving car over a long time can be challenge. Research "add a fuse" or "add a circuit". Remember to use a KNOWN good ground. Here's an example product. Basically what this is doing is giving an easy wire to attach the VOM securely to. Tape to prevent shorts/fire.

http://www.oreillyauto.com/site/c/d...-1_-1&mn=Littelfuse&mc=LIT&pt=N1177&ppt=C0172

If you think that the battery light has to be on to have an alternator problem we are starting out with one arm tied behind your back.

It also seems like a poor choice to swap an alternator as a trouble shooting step. Why not have it tested instead? Besides. What if the problem is really a missing motor to frame ground? Or a bad ground elsewhere in the car? The replacement alternator will behave EXACTLY the same way. But the VOM won't lie once the failing circuit is found.

If by chance all of the voltage readings are good, then you can move onto the next step with confidence that the charging system is in tip top shape.

Regarding the ForScan. Have you looked at any of the information on the ForScan site?

ForScan Windows documentation:
http://www.forscan.org/documentation_13.html
 
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#19
wmburns said:
Do you have a Volt-Ohm Meter (VOM)? If not, don't buy any other parts/tools until you have one. IMO it's not really possible to work on today's electronic cars without a VOM in the tool box. It doesn't have to be an expensive one but it does need to be accurate since you will be measuring small voltage changes.

Measuring battery voltage is as simple as attaching the VOM at the battery.

Monitoring voltage inside a moving car over a long time can be challenge. Research "add a fuse" or "add a circuit". Remember to use a KNOWN good ground. Here's an example product. Basically what this is doing is giving an easy wire to attach the VOM securely to. Tape to prevent shorts/fire.

http://www.oreillyauto.com/site/c/d...-1_-1&mn=Littelfuse&mc=LIT&pt=N1177&ppt=C0172

If you think that the battery light has to be on to have an alternator problem we are starting out with one arm tied behind your back.

It also seems like a poor choice to swap an alternator as a trouble shooting step. Why not have it tested instead? Besides. What if the problem is really a missing motor to frame ground? Or a bad ground elsewhere in the car? The replacement alternator will behave EXACTLY the same way. But the VOM won't lie once the failing circuit is found.

If by chance all of the voltage readings are good, then you can move onto the next step with confidence that the charging system is in tip top shape.

Regarding the ForScan. Have you looked at any of the information on the ForScan site?

ForScan Windows documentation:
http://www.forscan.org/documentation_13.html
Click to expand...
Ok i do have a volt meter and ive read a little bit about the forscan, i think i might buy it, so to test the charging system do i just touch the negative tester lead to the negative battery terminal and the positive to the positive battery terminal with the car running? What kind of voltage am I looking for?
 
#20
Motor off should be normal battery voltage 12.2 to 12.6. See why the meter needs to be accurate?

Motor running charging voltage should be 13.7-15 volts depending upon the battery's state of charge.

Turn on every accessory (AC, head lights, brights, brakes, rear defroster) even better. Let the motor reach full operating temperature when the cooling fans turn on. What is the voltage measurement? Is it above 12 volts? If so, the alternator is keeping up with load.

But the other thing that we are trying to confirm is what the voltage is doing when the problem occurs. It's all about change. IE, does the voltage drop or change when the problem happens?

Next put the VOM lead on battery negative and the other lead on the alternator case. This will measure the voltage drop through ground with the motor running. Should be low. Post.

Next put the VOM in the AC scale. Measure the voltage across the battery with the motor running. This will be the amount of AC ripple from the alternator. Should be low. Post.

Sounds like you could use a Ford service manual.

Exactly how have you determined the motor is over heating. Tell us all of the symptoms.

Tell us about the other things done to resolve this problem. Have the cooling fans been tested and confirmed working on BOTH speeds?

What about the pressure cap? Does it hold pressure? When it does over heat does it blow coolant? What is the condition of the coolant?

Under what driving conditions does it over heat? Stop and go city driving or highway cruising?

The details matter here as the information can help to narrow the focus.
 
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