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Motor Overheating @ 126 degrees after fuel upgrade. Why?

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Old Mar 16, 2003 | 11:24 PM
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Question Motor Overheating @ 126 degrees after fuel upgrade. Why?

I have did some modifications and now my car keeps overheating extremely fast up to 126 degrees. This happens as quick as 2 minutes after starting it up from being cold.

I will list the changes/modifications that I did and please let me know what you think the prob can be.

*Upgraded fuel lines/Tapped fuel rails for bigger fittings.

*Deleted the coolant line from the top of the water pump.

*Deleted and plugged the coolant line coming off the top rear of the motor block.

*Polished my water pump so I'm thinking I might have damaged my thermostat while sanding etc etc causing it not to open.

*Deleted my ABS









Okay, I had to move around my wiring harness quite a bit so I might have broken a wire or something there. Since the car overheats so quickly I'm thinking the thermostat isn't opening for some reason. Any way to test the thermostat?

If one of the sensors on the rear of the waterpump got damaged somehow or the wires to them got broken could this cause the car to overheat so quicky?

Thanks in advance for any help given
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Old Mar 17, 2003 | 01:10 AM
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126 degrees or celius? I believe the normal operating temperature is around 180 degrees. If you have a bigger radiator, you might still have some air in the system after those coolant mods, sometimes it's a pain to bleed all the air out.
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Old Mar 17, 2003 | 04:33 AM
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Yeah, 126 C is bad , but 126 F is nothing to worry about.
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Old Mar 17, 2003 | 07:38 AM
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My POWER FC is reading 126 so it's celcius. Also, it's puking through the overflow too.

Remember, this happens only 2 minutes after starting the car up from being cold. It happens super fast.

Any ideas?
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Old Mar 17, 2003 | 07:46 AM
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are you sure the motor is good? explain "puking" out of the overflow. if the compression in the motor is excaping through your soft seals it will cause pressure in your cooloing system and the only way out would be your overflow. if this is the case, are you refilling the coolant? if you are, is it burped all the way? when your turn on your heat, does cold air blow through or HOT air?
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Old Mar 17, 2003 | 07:48 AM
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test for your thermo is easy as putting it in a pot and boiling the water. use a thermometer to test the water temp and see if it opens at proper temp.
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Old Mar 17, 2003 | 07:52 AM
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even better yank the thermo out its easier and youre spark plugs see if you see any water deposits on them
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Old Mar 17, 2003 | 08:02 AM
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The motor is perfect, brand new. This only happened after I did all the changes that I mentioned above.

The sensors on the back of the water pump, if they were not working correctly. Could they cause this to happen? I'm not too sure what the job of those sensors are to do. I can't imagine them causing the engine to overheat to 126C in 2 minutes.

Actually it's not puking coolant out of the resovoir, it's just shooting steam out.
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Old Mar 17, 2003 | 08:14 AM
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Originally posted by Resource
The motor is perfect, brand new. This only happened after I did all the changes that I mentioned above.

The sensors on the back of the water pump, if they were not working correctly. Could they cause this to happen? I'm not too sure what the job of those sensors are to do. I can't imagine them causing the engine to overheat to 126C in 2 minutes.

Actually it's not puking coolant out of the resovoir, it's just shooting steam out.
alright, do you have your manual? look in it to find out what sensors do. what do you mean *deleted lines at the top of the water pump*? and i think you can rule fuel out of it. and are you talking about the line that used to feed your TB? i conected that line from rear to front cover. did not block it off. dont know that that would do anything though... are your fans comming on? what temp do you haev fans set for?
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Old Mar 17, 2003 | 08:34 AM
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I looked in the manual, it doesn't really give you an explanation of what the sensors actually do. I have no coolant going to my throttle body. The coolant lines that gos into the nipple on the top of the waterpump is now plugged. The nipple on top of the rear of the block is now plugged as well.

The fans are coming on right away so those are set at like 80C or so. It should have to do with something that I did while I had it apart just not sure what. I think I'm going to just put in a restrictor plare in place of the thermostat today and see what happens.

Thanks for the input guys. Keep it coming
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Old Mar 17, 2003 | 05:52 PM
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I gutted the thermostat so now it's a restrictor plate. This fixed the problem.
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