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Cylinder head and head gasket replacement for my Honda Civic

I have a 1997 Honda Civic that I was given by an elderly neighbor’s daughter after the elderly lady went to the grocery and ended up 100 miles away when she could not figure out how to get home. The car was smogged at the beginning of the year but when I got it ran very rough and the temp went nearly to overheating on the drive home when I was stuck in stop and go traffic. I found the radiator fluid level low and an oily residue inside the radiator water bottle. I took it to a mechanic to check it out and was told it had a blown head gasket and maybe worse. I am thinking of buying a rebuilt cylinder head and replacing it myself but I am not sure how to diagnose if any other damage could have been caused to the engine. It’s hard to know but I am guessing that the engine was damaged during the 100 mile road trip due to low coolant level. It turns out short term memory loss was the diagnosis for my elderly neighbor. I filled the coolant level and ran the engine for a bit and the temp stayed normal but the rough running remains. The oil dip stick shows no signs of coolant in the oil and the coolant looks bright green when I looked in the radiator after topping it up with some water.

Any suggestions on if there is a way to detect if I could be facing bigger issues like failed bearings? I am OK to do the head replacement but an engine replacement starts to get into the realm of what it would cost to get another car of the same age.

You are getting way ahead of yourself with a head replacement. How was the bad head gasket or worse diagnosed ? Many cars have an oily residue inside the overflow tank that signifies nothing.
Was the cooling system pressure tested? If it is necessary to replace the head gasket, send the head to a machine shop to be checked (remove the cams,springs and valves first and keep them in order.)

I’d run a compression test, both wet and dry before tearing it down. Severe overheating can ruin piston rings and this means that you could have a smoking, oil burning engine even after replacing the head.
A good cylinder should show 180 PSI and up. If a cylinder shows 130 for example and jumps to 160 during the wet test then the rings are gone, or going.

A cylinder head gasket breach into a cylinder or between a couple of cylinders will obviously show a problem. The purpose of the compression exercise is to determine if there’s a ring problem on cylinder with no gasket breach. A ring problem on one cylinder means an engine overhaul.
As to crankshaft bearings, one could test the engine oil pressure with an external gauge.

so… I can do a pressure test of the cooling system and also do a cylinder pressure test. The shop that did the performance check did not give me any numbers on the pressure test that they did. I am thinking that I will go back and ask for the data you suggest since they charged me for the check and did not give me any data. What about doing a vacuum test?

When I do these tests, particularly the wet cylinder pressure test, if I get a low number how do I know it’s the head gasket or valves? Since the failure came up probably after overheating, can I draw the conclusion that I have a leaky head gasket or cylinder head crack? It seems like it is still a process of discovery since it is possible it could be a cracked cylinder wall.

Thanks by the way for the feedback. Lots of good suggestions. The car is not smoky when started or during running. I know that if there is a leak of antifreeze into the exhaust I might see white exhaust smoke. Does that give me any clues?

There are a number of tests that should be performed before a definite head gasket diagnosis is given.
A compression test is the first one with a vacuum test (which may not be definitive), hydrocarbon test, cooling system pressure test, etc.
If you do the wet test (meaning a squirt of oil into each cylinder as you retest it) it can be assumed if the rings are bad that the readings will take significant jump upwards; say 25 PSI or more. If the readings do not go up or go up very slightly then that would point to a head gasket breach or valve issue.

It’s hard to say without knowing how the shop came to the conclusion that the head gasket was faulty.
I will say this. As a mechanic, I’ve seen many simple as ABC problems diagnosed as something major when in reality the real fix was quick and cheap and in my humble opinion compression readings or other critical information related to the repair should ALWAYS be written down on the customer copy of a repair order.

(Regarding a potential valve issue, valve lash should be inspected every 30k miles and adjusted as necessary. Seldom is this done; unfortunately. If a valve tightens up this can lead to rough running, cylinder head valve damage, and even overheating due to engine strain. If your wet test shows a valve problem then pop the valve cover and check the lash for tight valves.)

Hope some of that helps.

Yes, a vacuum leak can also be the cause of a rough idle.

So I did try to do a compression test. However, I turned up a new problem. All the spark plugs were torqued very tightly. I started with Cylinder 4 and removed each plug. After getting over the initial high force to loosen the first three, the effort dropped. On cylinder 1 the force stayed very high all the way until I got the plug out. Needless to say, the first two threads of the plug for cylinder 1 were cross threaded. I tried to complete the compression test, but the cross threaded cylinder 1 makes me doubt the value of the readings. I got: Cylinder 1: 90 psi, Cylinder 2: 135 psi, Cylinder 3: 145 psi, Cylinder 4: 150 psi. Since the compression tester can only go in hand tight, I have no confidence in the cylinder 1 reading. So now I am not sure what to do. With the overheating event I highly suspect some damage was done. Since the cross threaded cylinder head would either require replacement or a thread repair before I can really diagnose if there is anything else wrong I am stumped. I am also let wondering if the overheating event could have caused the plugs to all be very tight or cause the cross threading problem. Or did the garage that supposedly did the compression test cross threaded the plug on putting it back in? they certainly did not tell me that I had a cross threaded plug which I thought they would of if the condition pre-existed. Since I never took out the plugs before I have no proof that they caused the problem. Any suggestions on what to do next? I am inclined to take a pass on the entire engine and get a used or remanufactured engine.

From the sound of it the shop is at fault here in one way or the other. If they did not do the compression test as claimed and the plug thread damage/overtightening was already in place - they’re at fault.
If they did remove the plugs and reinstalled them in any kind of damaged condition - they’re at fault.

Those readings are all low. You could do this. Go back and retest the 135 and 145 PSI cylinders by adding a squirt of engine oil to each cylinder before you test it. If the reading jumps up significantly this means a ring problem exists.
This would make the 90 PSI cylinder a moot point and another engine might be the best route to take.
Hope that helps and good luck.

A spark plug thread chaser from an auto parts store isn’t expensive and will straighten out the #1 cylinder. Then put some never-seize on the threads and do a dry and wet compression test.

You could change out the head gasket, sure. But since this car is sort of like free money, you might get away with an easy fix. Probably what I’d do is change the oil & filter, and drain the old out and refill the coolant with fresh stuff. Next, I’d retorque the cylinder head bolts to Honda’s specs.

Then I’d cross my fingers and hope that fixed the problem. Monitor the coolant and the oil, checking for any cross-contamination and any drop in either fluid level. And check for white smoke out the tail pipe when you first start the car. If excessive, that could be a sign the problem remains.

If the problem is fixed, then bring all the routine maintenance up to Honda’s owner’s manual recommendations and you are good to go.

GeorgeSanJose,
Thats just like I used to do in college. It depends on this OP. Not bad advise since the OP seems to have a sense of the issue. But The guy who put in his spark and crossed it really should have paid attention, thats why he got paid the big bucks. As to head torque it is always good to check those if you have an issue. His other cylinders are not new but the compression is typical for age. Why rebuild up when the graveyard is closer. Also the oily reside is a question of how much. A table spoon of oil will cover the whole resevoir. Does that mean a bad head leak?

If the plug happens to set in a pocket where you can’t get the thread chaser try what I did several years ago on my '88 Escort. I was changing the plugs and one of them seized on it’s way out. When I got the plug out the aluminum from the head was filling the threads of the plug. I went and bought a thread chaser, but it was to large to fit into the pocket the plugs sit in. I took my old plugs and some oil and using as much pressure as I could on the ratchet/socket got one of the old plugs to start re-rapping new threads. I’d turn it about 1 or 2 revolutions take the plug out clean the threads and do it all over again until I had new threads cut all the way down. Maintain a lot of pressure all the way through the cutting process to keep it from stripping out the new threads. It will probably be important to remove the plug every little bit and clean the metal from the threads. That happened about 13-14 years ago and the new threads are still holding up. I figured it was worth a try to avoid having to pull the head to make the repair. When you put new plugs in be sure to use plenty of anti seize, this is a lesson I learned the hard way.

I think it’s time to get a used or rebuilt engine.
Google is your friend.

Thanks everyone,

Here’s my dilemma. I found a shop that will put in a remanufactured engine in for just under $1,000. Since the engine is at 109,000 miles I need to do a timing belt as well as fix whatever is causing the rough idle and check engine light. The engine starts right up and has no white smoke on startup. It’s smooth running although running at a fast idle when cool but gets rough running after warming up and has the check engine light on all the time. With parts the internet and my own labor I can do the timing belt, basic tune up, and put in a remanufactured cylinder head for about $500 to $600. So should I just put in the extra $400 to $500 and get a fresh start or cut out the extra expense and do the shorter job.

I am not in a big hurry to do anything so I will try a few more of the suggested tests. Based on the advice, I will finish the wet compression test and see if I can chase out the threads on cylinder 1. The money invested so far is pretty small so not much to loose except some time. One good thing is that I am learning a lot about engine repair which will help me in the future.

A reman engine for under a grand? How does that happen?

I will add that based on the poor compression numbers, which are quite likely ring related, installing a reman head and head gasket will probably generate an even worse problem due to increased blowby.

But did you try to fix the bad spark hole? This engine may have a good 20k-40k even on your numbers. If the spark hole is fixed properly. A new head is not a bad idea but you cannot diagnose the rough running issue until the bad spark hole is fixed.

Hello all,

Just to let everyone who made a comment know the outcome of my engine adventure here’s the conclusion. I decided to go for an engine swap with a rebuilt engine to replace my problematic engine. The cost turned out to be $1,190 which included a rebuilt long block with new bearings, water pump, timing belt, gaskets, plugs, spark plug wires, and a replacement distributor. The shop that did the work took the old engine apart to verify condition since they were taking it as a core for the next rebuild. They found three things wrong at least with the engine. They found a crack in the cast iron cylinder liner between cylinder two and three, a faulty distributor, and an arcing spark plug wire. I did not get a report on the blown head gasket but since they took the engine apart I don’t know if there was a way to confirm this was bad. Overall, I was glad to chose the rebuilt engine route since I was unlikely to be able to get a better repair unless I did it myself. Given that I don’t have a garage I could use for the work for more than one day, I really did not have the ability to do it myself.

I hope this works out but I’m having a near impossible time understanding how someone can not only sell a reman long block for a bit over a grand but to also include all of the peripherals that you mention.