Block leaking coolant
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Block leaking coolant
First off, i never had an overheating except when on the track - i need a oil cooler...
Also, do not post questions here, no one wants to read for 100 pages of the same thing being asked continuously to find actual useful information.
I am currently trying to diagnose if my HG is actually starting to go bad...
Plus the annual influx of overheating threads are starting to raise since spring - talk about winter tires questions during fall, for example
Anyway, the thing is that the Civic engine is not diagnosed as most of the other cars, rarely you will see coolant in the oil, or oil in the coolant, or leakage or any other common diagnose for overheating.
The top culprit is: the head gasket going out. It will slowly let the combustion gases pass through the gasket to the coolant.
What then happens?
1) The gases will heat the coolant
2) The gases will create bubbles inside the engine, reducing heat transfer
3) The gases will push the collant out of the reservoir.
A good giveaway are:
1) if when you open the rad cap there is "air", not coolant.
2) Heater blows only cold air. (could be a dead heater core, though...)
3) Coolant overflows the coolant tank - This is already on the extreme cases.
If these symptons are there, perform a gases test in the coolant - since they are combustion gases, they will be detected.
If positive above, need to change the head gasket.
Now, comes the trick part: If you drove too long with it overheating, you run the chances that the head itself warped due to heat. If so, need to take head to a machine shop to ensure that the mounting surface is even, as to not allow leakage (if warped, the gasket cannot conform to the warped surface and the new gasket will simply let gases pass.
If the noted above is not your case, then start checking for fans not working, leakages, and oh, the radiator cap - use always the honda. Aftermarket ones tend to cause troubles.
If your case is not listed in here please post a new thread with your case and when solved, it will be later updated in here.
There is another thread, but it is more general so i thought it could be misleading - it was not written for hondas.
https://www.civicforums.com/forums/7...ml#post1862929
one iof the last posters did correct the info, so i am posting it with the gasket in the top.
how to test? cheap way 1: Thanks, Scotty!)
2003 Civic Head Gasket Test - YouTube
Cheap method 2: (Thanks, ezone!, including your "own style" comment :P)
see original thread here - more details in there.
https://www.civicforums.com/forums/3...-ex-coupe.html
If anyone have more insight info, feel free to contribute
regards
Also, do not post questions here, no one wants to read for 100 pages of the same thing being asked continuously to find actual useful information.
I am currently trying to diagnose if my HG is actually starting to go bad...
Plus the annual influx of overheating threads are starting to raise since spring - talk about winter tires questions during fall, for example
Anyway, the thing is that the Civic engine is not diagnosed as most of the other cars, rarely you will see coolant in the oil, or oil in the coolant, or leakage or any other common diagnose for overheating.
The top culprit is: the head gasket going out. It will slowly let the combustion gases pass through the gasket to the coolant.
What then happens?
1) The gases will heat the coolant
2) The gases will create bubbles inside the engine, reducing heat transfer
3) The gases will push the collant out of the reservoir.
A good giveaway are:
1) if when you open the rad cap there is "air", not coolant.
2) Heater blows only cold air. (could be a dead heater core, though...)
3) Coolant overflows the coolant tank - This is already on the extreme cases.
If these symptons are there, perform a gases test in the coolant - since they are combustion gases, they will be detected.
If positive above, need to change the head gasket.
Now, comes the trick part: If you drove too long with it overheating, you run the chances that the head itself warped due to heat. If so, need to take head to a machine shop to ensure that the mounting surface is even, as to not allow leakage (if warped, the gasket cannot conform to the warped surface and the new gasket will simply let gases pass.
If the noted above is not your case, then start checking for fans not working, leakages, and oh, the radiator cap - use always the honda. Aftermarket ones tend to cause troubles.
If your case is not listed in here please post a new thread with your case and when solved, it will be later updated in here.
There is another thread, but it is more general so i thought it could be misleading - it was not written for hondas.
https://www.civicforums.com/forums/7...ml#post1862929
one iof the last posters did correct the info, so i am posting it with the gasket in the top.
how to test? cheap way 1: Thanks, Scotty!)
2003 Civic Head Gasket Test - YouTube
Cheap method 2: (Thanks, ezone!, including your "own style" comment :P)
see original thread here - more details in there.
https://www.civicforums.com/forums/3...-ex-coupe.html
If anyone have more insight info, feel free to contribute
regards
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Re: Block leaking coolant
is it really true that there is another o-ring that goes in the front of the block and if I just take those 2-3 bolts off you can easily replace the o-ring and stop the leak .. and is there any other place I should check as well, in case this motor wants to leak out from another spot. any advice and/or help would be greatly appreciated. p.s. i know that my motor itself is probably done and I do plan on throwing a swap in soon , but right now I need this car to last for a few more months. without losing all of its performance (i like my vtec) lol and these leaks are causing me to lose power
If your engine has lost performance there is probably a compression leak between one or more cylinders due to blown head gasket. Do a compression test to confirm. If you know for sure you are going to swap the engine soon and don't want to spend between $350-500 for a proper head gasket repair (inludes machine shop the cylinder head) your options are limited to pulling a head from a junkyard and using a straight-edge and feeler gauge to check for warping..must be under .004 inches for both block and head for a head gasket to seal properly.
That blue ***** head gasket spunk you poured in might clog up the heater core and radiator. Might be best to flush the coolant system by draining the radiator and block (17 mm bolt near knock sensor).
Last edited by Wankenstein; Nov 28, 2015 at 01:43 PM.
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