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I have a 1993 Honda Civic DX Hatch with 338k miles. We have owned it since new, and it is completely stock.
BACKGROUND
Over the last 2 years and about 3k miles I have done the following, clutch master and slave, clutch (was original), new tires. About 4 months ago it was running odd, occasional low power, I took it into the shop and it needed a timing belt. 1 of the teeth was missing and it would jump timing. They replaced the timing belt and it ran great again. About 2 months ago, the fan sensor (at the thermostat) went out. The car overheated while sitting at a red light, it was replaced and ran great again. About 2 weeks ago, it started idling rough and stalled a couple times on me on the way home from work (about 7 miles). I parked it and thought it might be the ignition side, so I replaced the plugs and wires (NGK). Same issue, I ordered a new distributor since I saw a little oil in the cap while I was replacing the cap and rotor. Since these distributors are known to go bad (on my 3rd or 4th), I decided to replace it. The same issues persisted, I looked at the PCV valve next and it was clogged, thought I found the issue. Replaced it with an OEM (splurged on that part). The issue was still there.
I took it to my local shop and they did a compression test and found that cylinders 1 and 2 were at about 170-180psi, cylinders 3 and 4 were at about 50psi. The car does not run hot and I do not see any coolant in the oil, or it is not enough to cause the oil to turn whitish. They stated I was low on coolant. They did not do a leak down test as they felt it was wasting my money since they were sure it was the head gasket.
Is there anything else I can check to rule out a larger problem? I can probably handle the head gasket replacement with the help of a couple friends, but don't want to throw more money at the problem without ruling out any other issues.
It has been a great car and we have gotten our money out of it. I did have an issue in 2004 with a bad radiator that caused the head gasket to blow a couple months down the road, that was at about 280k miles (mostly highway miles). I had the head gasket replaced and the upper part of the engine rebuilt make sure no other issues would pop up and to get more life out of it. That was when the timing belt was last changed, so age was the issue not miles. So I have only driven the car about 55k miles in the last 12 or so years. I worked from home most of the time and rarely drove it over the last 9 years as we had an Odyssey and other cars better suited for a family.
As you can see it is still in good shape for its age and miles. That is the original paint.
I can't believe that they had it all opened up for a compression test, have the leak down tester and were going to charge you extra just to slap it on and spend an extra 10 minutes gathering info.
Anyways, it will either be head gasket, bad valve seating, or a cracked head or block.
The cracked scenario is nearly impossible to identify until the head comes off. In which case you can also identify the head gasket failure.
The leak down would have told you if it was the valves not seating properly anymore.
As for them not doing the leak down test. They had notified me of the compression issue and what they thought the issue was. I only asked them for the leak down test the next day. So it wasn't at the same time that they performed the compression testing.
Shouldn't I see milky oil, white smoke from exhaust, or overheating with a blown head gasket? I don't see any of those issues.
It is possible for a head gasket to blow out in the section between two adjacent cylinders and not involve the water jacket.
Take the valve cover off and check that when you rotate the engine to where all the valves on those cylinders should be closed, the rocker arms go slack. But not real slack, which would indicate a bent valve from having the belt go out of time.
But, the leakdown test is really the definitive thing to do in this situation. If you already have an air compressor you only need to buy a basic compression test kit to do it.
you can do a poor mans leakdown test. 12v air compressor connected to compression gauge fitting. Put in spark plug hole and listen.. If you hear hissing out of the intake or exhaust you have bad valves. If you hear/see bubbles in the radiator you have either a cracked head or bad head gasket.
If you don't want to do another head gasket, sell it for the highest price you can. I think you may be
surprised how much you could get for it, even with a smoked engine.
There's several types and signs of a head gasket breach. Typically strongest sign of a head gasket leak in a Honda engine is coolant loss in radiator combined with coolant gain in reservoir. A block test is always a good place to start. WIth overheating there's always a possibility of damaging the cylinder compression rings, warped cylinder head and even a warped block (but, much less likely). Did the mechanic do a wet (one tablespoon of oil in cylinder) too. That would help rule out a damaged compression ring.. after adding the oil if the compression increases it points to damage to the compression ring.. if, no change in compression then the compression loss is either through the head gasket, intake and/or exhaust valve,valve guides,damaged or weak valve springs. As others stated when two adjacent cylinders are low in compression it does point to a head gasket breach bwteen the two low cylinder which can also be detected by a leakdown test that would further isolate compression loss via head gasket vs valves vs cylinder compression ring.
I think a lot of mechanic shops would jump to a head gasket conclusion based on the two adjacent cylinders low in compression and because they will most likely send the head to a machinist to check for warping, cracks, valve leakage and valve springs tension anyway. Still, the proper way to find out the most information first to properly isolate the compression loss is with a leakdown test. You can ask them if they are willing to do one and it isolates the head gasket if they will not charge you for the leakdown test if, you agree to have them do the head gasket repair.
- Mechanic did say there was bubbling in the coolant/reservoir during the compression test
- After the timing belt was changed they also cleaned the throttle body. The intake was much louder than before (stock intake). and had a lot more suction.
Not sure if either of those are related, but thought I would throw it out there
> They did not do a leak down test as they felt it was wasting my money since they were sure it was the head gasket.
This seems consistent with the information you've given, but so are other explanations. I'd be wary of a shop that jumps to a conclusion without running a simple test that could save you a lot of money in the long run.
If they're so sure it's the headgasket then have them put it writing that if they repair it, and after repair it still has compression loss that they have to fix it at their cost or refund you in full for the cost of head gasket replacement. See how fast they run from it..lol
Or bring somewhere else for a second opinion/leak down test.
As mentioned a leak down test is needed, although low compression on adjacent cylinders is a sign of a blown HG, [between those two cylinders] it does not necessarily involve water jacket although bubbling into the overflow is also a sign of a blown HG, either way at this point the head needs to be pulled. 94
11-20-2016, 08:02 AM
Bad head gasket? Something else?
