97 civic hx 225k still getting 42 mpg but turning oil black and runny quickly. Tried 15w40 to see if it would hold up better but same result. After 500 miles the engine does not like to be revved and is noisy. If I change the oil its good for 500 miles then same problem. Has good compression. Assume it's not a leaky injector since I'm getting great mpg and running strong. maybe a uoa? Dont know what else it could be aside from fuel in the oil
oil black and engine noise 500 miles after oc
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Maybe the noise is coming from valves in need of lash adjustment. Just a guess.
You shouldn't have to use 15w40. The oil getting black in 500 miles is very peculiar to say the least.
You shouldn't have to use 15w40. The oil getting black in 500 miles is very peculiar to say the least.
Originally Posted By: bvance554
What exactly is your complaint here? That the oil is turning black? You're getting good fuel efficiency and you say its running strong at 225k miles. I don't understand or see your problem.
His complaint is that the oil is black and runny and the engine is noisy.
What exactly is your complaint here? That the oil is turning black? You're getting good fuel efficiency and you say its running strong at 225k miles. I don't understand or see your problem.
His complaint is that the oil is black and runny and the engine is noisy.
cracked head,head gasket or valve seal. leakdown test needed.
uoa should show dilution , but motor might grenade by then.
I'd have the test and new head ready.
Timing belt and water pump too.
Honda's are great until they fail. Then it is usually major.
Keep us posted
uoa should show dilution , but motor might grenade by then.
I'd have the test and new head ready.
Timing belt and water pump too.
Honda's are great until they fail. Then it is usually major.
Keep us posted
Is it overheating?
Black sounds like carbon blow by. Runny sounds like fuel dilution. Both come from running rich and/or worn rings. At 225K, both are good possibilities.
Valves were adjusted this year. Then I rechecked then just to make sure nothing was off. Pcv is new Honda part. Compression is 175 across the board save for cylinder number three which is 165. Have not performed a leak down test yet. Don't have the tool. I've tried everything I can think of with this car which is why Im posting. The oil gets black and the engine becomes noisy. Before the oil turns black the engine runs like
A Top all the way to redline.
A Top all the way to redline.
Alright, so the oil turns black quickly, and engine makes more noise than usual. No other issues. Gotcha. Just to verify, you're changing the filter too, and this noise is at any time the engine is running (hot or cold)? Can you hear this noise while on the highway, or just at idle, or __?
What oil are you using? Prior to the 15W40, and after the 15W40? I haven't a clue what oils are "good" in this sort of motor, but perhaps others here would have a recommendation.
I see you are in NJ, but you are getting 42mpg... Mostly highway miles? Long trips, no long idle times, etc?
Not familar with the lean burn engine; am guessing white plugs go with that territory. No issues with overheating though? No coolant loss etc? I'm kinda grasping at straws here, but perhaps there is something else going on, seemingly unrelated, that may help to shed light.
What oil are you using? Prior to the 15W40, and after the 15W40? I haven't a clue what oils are "good" in this sort of motor, but perhaps others here would have a recommendation.
I see you are in NJ, but you are getting 42mpg... Mostly highway miles? Long trips, no long idle times, etc?
Not familar with the lean burn engine; am guessing white plugs go with that territory. No issues with overheating though? No coolant loss etc? I'm kinda grasping at straws here, but perhaps there is something else going on, seemingly unrelated, that may help to shed light.
Yep changing filter also. Prior to this oil I had run honda spec 5w30 or 20. Cant remember what it called for but I was getting the same result. The noise it more prevalent at higher rpms (+3k) and under load. Idle may be slightly noisier but not too noticeable. My driving varies. 42mpg is mostly highway and I get about 39 in the city. No long idle times. Car does not overheat at all even in dead stop traffic and 90 degree temps with the AC on.
Well, you might have two issues: I believe Honda's of this vintage need their valves adjusted every so often; perhaps something is loose. That should be separate from the oil turning black, unless if something is disintegrating and fast.
On the oil changing black, did it suddenly start turning black overnight; or has it been slowly getting black as the years have gone by?
Personally, unless if the oil has suddenly started getting black, I'm leaning towards loose valvetrain, increased blowby and/or possibly worn bearings. Might want to get a good mechanical oil pressure gauge onto it, and watch pressure as you motor down the road; I'm wondering if the oil is thinning out a bit and the noise is from the valvetrain and might be compounded by low-ish oil pressure. A leakdown test might be good, or a borescope to look at the crosshatch in the cylinder walls.
If the valvetrain is ok, and oil pressure ok, I'd probably just run it. Run shorter OCI's, sure; I'd be tempted to use dino and change at 3 to 4k, if it is getting good and black.
I'd be curious if you were getting any buildup under the valve cover. If there is no buildup of crud, I might not even short-change the oil change interval.
On the oil changing black, did it suddenly start turning black overnight; or has it been slowly getting black as the years have gone by?
Personally, unless if the oil has suddenly started getting black, I'm leaning towards loose valvetrain, increased blowby and/or possibly worn bearings. Might want to get a good mechanical oil pressure gauge onto it, and watch pressure as you motor down the road; I'm wondering if the oil is thinning out a bit and the noise is from the valvetrain and might be compounded by low-ish oil pressure. A leakdown test might be good, or a borescope to look at the crosshatch in the cylinder walls.
If the valvetrain is ok, and oil pressure ok, I'd probably just run it. Run shorter OCI's, sure; I'd be tempted to use dino and change at 3 to 4k, if it is getting good and black.
I'd be curious if you were getting any buildup under the valve cover. If there is no buildup of crud, I might not even short-change the oil change interval.
Valves are to spec. I adjusted them this year then rechecked them to make sure. I like the idea of an oil pressure gauge. I will rig something up. The valve cover was very clean last time I had it open. I may pull it again just to have a look around. I have only had the car for a year and have replaced many things. This is a newer issue. My only issue with running the oil for 3k is the noise. It does not sound good. Valvetrain noise etc.
sure sounds a lot like fuel dilution
make sure the PCV valve is getting vacuum; no clogged hose or manifold fitting.
If you're sure the valves are good, and you are getting okay oil pressure when it's hot (after 500+ miles into your OCI); I would do a UOA after 2k or so miles. If it shows that everything seems to be okay, I would drive it till the wheels fall off.
Your oil getting black in 500 miles doesn't concern me, but the noise could be an issue. 500 miles isn't very long on oil to thin it down, unless there's a fuel issue.
Your oil getting black in 500 miles doesn't concern me, but the noise could be an issue. 500 miles isn't very long on oil to thin it down, unless there's a fuel issue.
Spend the bucks on an oil analysis, along with someone educated on how to understand what the numbers say! No harm meant to all the other posts here, but a UOA will zero in on "exactly" what's going on in that engine.
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