Hello,
I have a 1993 Honda Civic DX.

For the last year or so I have noticed that my coolant has been dropping. It started off as a little bit and has gotten to the point where in about 2-3 months I will lose almost all coolant. I had assumed I had an external leak somewhere (even though I couldn't see any coolant dropping), but procrastinated having my radiator checked. In the past I have also taken a compression test of my cylinders and they all read in the low to mid 90's which I know is quite low. I again thought perhaps all the cylinders were just old without taking into account other possibilities for pressure loss in all at once.

So my car has been sitting for a month while I have been gone and when I started it up it I noticed a bit more stumbling in idle. I drove about 5 miles and noticed it got a bit worse. I also noticed the heat rising (my clue that the fluid is low in the past) and so I pulled over and filled the radiator with water. This is where things went from bad to worse.

When I tried to start the car it really struggled and idled horribly. I decided to try and drive it home but as I backed out of the spot I noticed a large puddle of fluid where my muffler was. I quickly parked the car again the looked in that area as it idled very roughly. What I saw was a large amount of water/coolant leaking out of the muffler and the joint where the muffler meets the exhaust pipe. I tried driving it home further but then I realized what may be going on and that the water in the oil would be killing the viscosity so I pulled over.

The car is back at the house and I'm pretty sure I didn't do any internal damage but here is my question. With little to no water in the system it drove pretty well but idled poorly. Once I filled the system with water, it seems the water made its way into the engine and out the tail pipe. My guess is this caused the engine to drown in the water and hence the poor running which then I would guess reduced the viscosity of the oil which ultimately would have caused engine damage had I continued to drive.

Considering all this....is it my head gasket that is blown...does the amount of water that was coming out point to something larger than a head gasket...(i.e. head crack)? Or, am I completely off and it's something else?

P.S. I can get the engine to turn over and start but don't want to push it any further by trying again.

Thanks in advance.

 

get a combustion leak tester.

 

Or fill up the radiator start the engine (cold) with the cap off and rev it for a few seconds. If you have bubbles or coolant blow out of the radiator, the gasket is blown. Taking the head off would be necessary to investigate further. Often if the car has not been driven while seriously overheated, a new gasket will fix it. Also change the oil because there's bound to be some coolant in there.

I hope that you haven't been using plain water in the cooling system all along because that will cause serious corrosion of the engine. You can fill up with water to get home but always replace it with antifreeze mixture immediately, even when freezing isn't an issue.

 

Thanks for the information. I'll admit that there have been periods of time that I have used only water...and know better. These periods of time have not been long though and I have some concentrated coolant I add to balance out.

Just out of curiosity...other than the water pump....what parts of the engine are susceptible to only using water?

P.S. I made the decision to go in and start the head removal process. Other than a stripped nut on one of the intake bolts...all is going well. Should have head off tomorrow.

 

So I removed the cylinder head today and the head gasket was toast. I saw at least 2 places with very larger blowouts that would account for the amount of coolant I was losing out the muffler.

I have a few questions. I am very confident that I set my engine to TDC on the compression stroke but I have noticed that on two cylinders...two valves are slightly open. I believe they are on cylinders two and three. One pair seems to be the exhaust valves and the other appears to be the intake. The cylinders themselves on 1 and 4 are completely perfectly at the top (which I assume is how it should be). Is this normal to have some valves open at TDC?

Also, is there an easy way to remove the two guides that are stuck in the head?

Thanks

 

On the valves, that is normal it is how the cam works. Those valves should close (and others open) if you turn the camshaft a little.

The guide pins (more properly cylinders) should pull out with little force on pliers. The holes in the head and the block are the same size (a very close fit) so when you remove the head they may end up staying with either part. Put them both in the block when you re-assemble so that they hold the head gasket in position.

 

Thanks mk378. I've tried tugging a bit on them with pliers but no luck. I'm a bit nervous about bending or damaging them. I plan on putting some penetrating oil and let it sit.

Do you have any suggestions on a solution/cleaner that could be used to soak the head and loosen any grease/particles in the passageways?

 

seafoam works good but its not cheap i hear some people use kerosene.

 

I noticed online a few suggestions about using a bolt to wiggle the guide cylinders back and forth. This worked like a charm.

Everything has been going well through the whole process of cleaning, etc. Knowing myself this has made me a bit nervous because it always seems like a do something stupid along the way. Well, today was that day.

After watching plenty of videos and reading about cleaning and lapping the valves I decided I would give it a go. I got the rocker arm assembly off and was going to clean it. As I started to move it around it began to come apart. I don't know why...but I just didn't give this a thought as a possibility. Long story short...the rocker arm assembly is now in pieces. I've found a schematic on how it should go back together.

Here is my question. Is there anything that I should know...or for some reason I should not consider this? It seem pretty straight forward. So far I haven't found a relevant video for my type of D15B7 engine.

It's nice to know the stupid part of myself shows up every project.

 

There's no harm in lapping the valves a little but it seems overkill if you're just trying to get your daily driver running again. Be sure to put oil or assembly lube back on all the bearings if you clean them with solvent.