Got a '02 Honda Civic LX sedan with a D17A1 engine on 5/14/18. The car is in LIKE-NEW condition, but with a 6/23 odometer reading of 184,843 miles.
The car ran great for a while, then the engine started overheating. I then noticed an overfilled coolant reservoir with a small stream of bubbles in the coolant. I assumed this was caused by exhaust gas leakage through a blown head gasket (like my last Civic, a '99). I replaced the head gasket with an aftermarket (MLS) part from Evergreen Parts on Amazon.com (NEVER AGAIN!). I inspected the head surface for excess warpage. A 0.002" feeler gauge was a go in some places, a 0.003" gauge was a no-go. I thought this was within the 0.002" service limit. I put the engine all back together with a new timing belt, tensioner, valve stem seals, (OEM) thermostat & synthetic oil. The engine ran great for a while but now the exact same symptoms are back. The engine is overheating with bubbles in the radiator neck. The electric fans work as they should. There is no white smoke from the exhaust. There is no evidence of coolant in the oil. I tested for exhaust gas in the radiator filler neck (on Sun 6/24) and it was POSITIVE. I think this means I can stop testing. Clearly, there is a leak, my only remaining question is WHERE? (e.g. head warpage, head crack, block crack). I've ordered an OEM gasket set and I plan to have a machine shop shave the head after I pull it AGAIN. Do y'all think I on the right track? Any advice for me?

that's why everyone one here recommends using a honda gasket.
did you make sure to bleed the coolant properly?

Sometimes it doesn't pay to cheap out. Besides a Honda genuine (oem) headgasket is around $30-$40 on HondapartsNow.

Do you own a professional precision straight-edge level (cost hundreds $)? If not, then your measurements are not exact. If an aluminum engine overheats even once then there's good chance the head is warped out of spec. Did you check the block too? Even though it's far less likely due to it's thickness the block's mating surface can warp out spec as well.

Rarely happens with Honda engines. There's many types of headgasket leaks (link in my signature) and the most common with these engines is loss of coolant in the radiator and gain of coolant in the reservoir.


Yes. However, not all types of head gasket leaks will be detected by a block tester. Since yours tested positive (blue fluid turned green or yellow) then it (combined with symptoms you described) confirm a leak is allowing exhaust gases in the coolant.

Now that's thinking with your dipstick Jimmy:

Adhere to the service manual: follow torque spec, bolt sequencing, etc..
Get the block's head bolt hole threads as clean as possible and make sure they are absolutely dry before inserting the head bolts. Spray the bolt hole threads with brake cleaner and blow them dry with compressed air.

use a light coat of oil on bolt hole threads prior to insertion. Bleed coolant per service manual afterwards. After repair drain oil, leave the drain bolt, pour in a quart of oil and let drain out immediately...this will help remove coolant that is most likely sitting at the bottom of the oil pan due to overheat. Replace oil filter, reinstall drain bolt and after a day or two of driving do another oil and filter change. Buy the cheapest oil and filters for the first change.

I will NEVER AGAIN deviate from using OEM parts exclusively on Honda!
My experience now trumps everyone's opinion! :-)
I bled the cooling system per the FSM.

That's a fail IMPO.
I use only Genuine Honda here.
I sure hope that was Genuine Honda too. There have been FAR TOO MANY failures of aftermarkets, and failure can be quite costly.
Agree, unless you want to narrow it to specific cylinder(s).
Look at the original finish of the block and head, they are almost as smooth as glass. Make sure your machinists equipment is good enough to duplicate the original finish, hopefully 30RA or smoother. A surface that's machined too rough can dramatically shorten the life of the new head gasket.

If you prepped surfaces with a whizzwheel or similar (die grinder and scotchbrite pads) to clean it up, you could have caused surface damage as well.