1999 Honda CX with 186k miles. The car is all stock.

I've had it for a year, it was driving fine up until lately when it started overheating. I thought the old rad might be clogged as it's a common issue so i bought a new rad and thermostat. Everything was fine for about a month when it started overheating again. It seemed as if coolant was getting pushed out into the reservoir.

I bled the system 3 separate times, which didn't do much, the overheating would start even faster. There is no sweet smell from the back of the exhaust and the oil look clean, not milky, I also don't have any foaming at the oil cap after the car has been running (all symptoms of bad head gasket).

The car overheated again today in traffic, i turned the blower motor high and put the heat on, it did nothing. Coolant once again was pushed out into the reservoir. I waited for 30 minutes, opened the rad and poured the coolant back in just so I can make it home.

At this point I am at a cross roads...do I change the head gasket or do I replace the whole engine. I can do either, so it's not an issue. The problem is with used motors I don't know what I am getting and I don't want to have to do this again in a few months. Despite the high miles on this motor, it has been running fantastic, doesn't burn oil, oil is always clean, etc.

I pulled the head off today and I don't see any visible damage to the gasket it self. I've attached these pictures for those more experienced to chime in and tell me what's going on here. Input is appreciated.

BTW, when I pulled the head off, oil leaked into the cylinder walls, hence why the coolant is mixed.

 

Check, or have the head checked, to see if it warped.

 

Is it possible for the head warp if the motor never really overheated? I never let the engine get passed like 3/5ths on the guage, and that's happened maybe 2-3 times since i've owned and never for more than 2-3 seconds until I'd shut it off.

 

So has it been overheating or has it not? Overheating and coolant being pushed into the reservoir sounds like a warped head to me.

 

When I say overheating, the temp guage would go above half but never over 3/4 because i'd turn the car off, and i'd never let it get and stay that high for more than 2-3 seconds.

 

Now that I think about it, one of the middle head bolts that I had to undo was SIGNIFICANTLY easier to undo than the rest, it almost had no resistance.

 

Pics of plugs

 

You already did most of the work, change out the gasket, get the head checked, put back together.

But I would of troubleshooted first, like check the thermostat, fan switch, water pump working etc.

 

id cross the jumper on the fan....see if that turns on. HG looks great for 200k miles...however by pics I'd be hard pressed to tell if its off a 1/100 of an inch or so, lol.
too many variables though....warped head, etc...you got the hard part done, and a hg is a couple bucks...change it. get the head checked/decked whatever it needs.

and not for nothing but I wouldve really put the motor at tdc being sliding that t belt off. I am super nervous about timing an engine. most likely you'll be fine, however it takes a couple seconds to put her at tdc...and piece of mind is alot easier then timing that baby

 

Thermostat is brand new and working.

Fan is also working.

Water pump isn't leaking, I haven't checked, but I don't see why it would push coolant back in the reservoir.

 

replace the water pump now dude while everything is taken apart if you haven't already.

 

Put a straight edge on the head to see if it's warped. If it is take it to a machine and ask their opinon on repairing it.


replace the head gasket, water pump, and the head bolts. might as well do the timing belt as well, check the tensioner also.

 

A Honda mechanic told me that sometimes the block or head can get a hairline crack and you can lose coolant. I think he said they can put a dye in the coolant and run the car for a while then put it up on a lift and look the motor over with a black light to see the dye leak.
Not a bad thing to do before tearing in to an engine.

Also if one spark plug looks especially cleaner than the others it might a crack in the head or the head gasket by that plug and the plug is getting steam cleaned by the coolant.

 

Cylinder #4 appears to have been burning coolant, note how clean the top of the piston is and the white on one of the valves.

 

also just an FYI one of the headbolt holes COULD be stripped out if one of the bolts were easier to take off then the rest, just went through this on my engine and had to timecert it

 

i have rarely seen those steel gaskets blow but i guess they can. check head for warpage and put a new gasket on and check if it overheats if it does than its not the gasket

 

well i havent done a d series headgasket but if its a multi layer meatle gasket the layers could of seperated