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Honda techs? 1997 Honda Civic owners? I need some help trying to figure out why my 97 D16Y8 has always had a condition of dirty deposits on the underside of the valve cover and valve train?
I've owned my 1997 Civic EX D16Y8 since 2001 when I bought it with 40,000 miles from the original owner.
The original owner had full documentation on oil changes and scheduled maintenance by Honda dealers.
From the beginning I took to changing the oil myself every three months which has always been less than 3,000 miles.
When the time came for the 60k scheduled maintenance, I had preformed approximately six oil changes myself.
When I picked the car up from my local Honda dealer after the 60k service, the service writer asked me what I did to cause the deposit buildup to the underside of the valve cover and valve train? I was completely perplexed???
The oil changes and scheduled maintenance have been impeccable through out the live span of this car. Yet, every time a mechanic opens the engine for service, the same condition of dirty deposits get noted on the invoice.
More recently, I tried Used Oil Analysis and found I was running about 2.1%-to-3.7% fuel dilution, which is high comparatively. Tracking my fuel economy on Fuelly.com, with about 88% city driving I'm averaging 27.3 MPGs
The question remains. Why is my Honda a deposit building, fuel diluting pig???
If I'm reading correctly, you've only put 20k miles on the car in 15 years.
Oil breaks down over time. It's not just the amount of miles, but the amount of time between the oil changes that cause it to sludge up.
No, sorry. I was just chronicling the first year or so of ownership. The car now has 164,000 miles on it. This condition has been consistent over the years.
A mechanic asked me how often I changed my oil. I said approximately 1,000-to-1,200 miles in a three month period. He said try 800-miles then. Never would have thought in a million years a Honda engine would be so hard on oil. Something that continues to perplex.
One thing about driving habits. I've always lived close to my place of work, as in three miles both ways. I also live in a smaller city. I can get to where I need to go in ten miles or less. So it's stop and go driving for sure. Yet, my brother in-law has a 99 Civic EX with similar miles and driving conditions. He cares for his car way less than I do mine. When I look into his valve train through the fill hole, his looks deposit free.
Things I've done to try and correct the issue. New PCV valve. New spark plugs, wires, cap and rotor. New fuel pressure regulator. Fuel injectors professionally cleaned and flow tested. New O2 sensor.
You should try to take the car to full throttle red line one time per tank of gas to reach maximum oil pressure. It sounds stupid but I had a similar problem with my wife's trans am having higher than normal oil pressure at idle after sitting for a few years. I performed a flush with the proper amount of seafoam and then when she's not looking I'll take it out once a month and take it though the gears.
I can't say it will fix your problem, but it will help get high oil pressures and start blowing off the deposits with higher oil pressure. Could also explain why your buddies abused ex doesn't have deposits, he beats on it and the extra oil pressure is cleaning up the deposits and getting them into the oil filter
I only say once per gas tank because that is the interval required on a mazda rx8. I'll admit it's a dumb theory. But it was my $.02
You should try to take the car to full throttle red line one time per tank of gas to reach maximum oil pressure. It sounds stupid but I had a similar problem with my wife's trans am having higher than normal oil pressure at idle after sitting for a few years. I performed a flush with the proper amount of seafoam and then when she's not looking I'll take it out once a month and take it though the gears.
I can't say it will fix your problem, but it will help get high oil pressures and start blowing off the deposits with higher oil pressure. Could also explain why your buddies abused ex doesn't have deposits, he beats on it and the extra oil pressure is cleaning up the deposits and getting them into the oil filter
I only say once per gas tank because that is the interval required on a mazda rx8. I'll admit it's a dumb theory. But it was my $.02
Thanks for the reply.
My rout to work has a steep grade. The drive to work, the engine won't reach full operating temp. The drive home, typically, at the on-ramp, I will kick the engine into Vtec one or more times during my work week. I'm sure the engine reaches full operating temp three-to-four times weekly, some of those a result of hitting red line or full Vtec mode. I wouldn't say I baby the throttle. My brother in-law's 99 EX is an automatic and he isn't a motor-head. I imagine his car rarely if ever hits Vtec. In fact, I doubt he knows what Vtec is.
I just can't imagine why a modern Honda engine, properly maintained, and with modern SN/GF-5 motor oil has had and continues to have this chronic issue with valve train deposits??? Apparently, I'm the only one who's experienced this???
My rout to work has a steep grade. The drive to work, the engine won't reach full operating temp. The drive home, typically, at the on-ramp, I will kick the engine into Vtec one or more times during my work week. I'm sure the engine reaches full operating temp three-to-four times weekly, some of those a result of hitting red line or full Vtec mode. I wouldn't say I baby the throttle. My brother in-law's 99 EX is an automatic and he isn't a motor-head. I imagine his car rarely if ever hits Vtec. In fact, I doubt he knows what Vtec is.
I just can't imagine why a modern Honda engine, properly maintained, and with modern SN/GF-5 motor oil has had and continues to have this chronic issue with valve train deposits??? Apparently, I'm the only one who's experienced this???
I think you're the only one ocd about it. Discoloration is normal, sludge and carbon deposits are abnormal.
I think you're the only one ocd about it. Discoloration is normal, sludge and carbon deposits are abnormal.
Yes, I'll own that. I am OCD when it comes to my auto maintenance. The thing to remember though is any Honda specific mechanic who has removed the valve cover over the last 15-years has said essentially the same thing; "what are you doing to cause the build up under there???". I figured a Honda mechanic who removes many Honda valve covers has some sense of what is normal and what is abnormal. In fact, one mechanic said he tried to remove the hard baked on deposits with a trip to the solvent tank but to no avail.
Yesterday, I did the fall oil change and snapped a pic of what can be seen beneath the oil fill cap. It's not much, but I'll post it up later when I get a chance.
Looks clean to me, compared to my valve cover which was stained brown yours is still a golden chrome. The darker color inside on that one piece could just be rtv from whenever the last technician did the timing belt, instead of a new gasket they probably just used rtv under the old gasket. So your seeing that one dark spot but the rest looks fine
Now if you're checking your oil lever after an oil change and notice it immediately turns dark you have a contamination problem, but your oil looks very clean as well as the valve cover
Looks clean to me, compared to my valve cover which was stained brown yours is still a golden chrome. The darker color inside on that one piece could just be rtv from whenever the last technician did the timing belt, instead of a new gasket they probably just used rtv under the old gasket. So your seeing that one dark spot but the rest looks fine
Now if you're checking your oil lever after an oil change and notice it immediately turns dark you have a contamination problem, but your oil looks very clean as well as the valve cover
I can assure you that it's not RTV. It is a hard baked on dark brown/black deposit. I can feel it on spots I can reach with my finger on the inside of the valve cover as well. It's the same hard baked on deposit a mechanic said he could not remove with solvent. If you compare your pics to mine, your cylinder head does not have this same depositing in your engine with nearly double the mileage.
Last edited by CompSyn; Sep 26, 2016 at 10:28 AM.
Reason: add pic
What brand oil are you using in your cars. Brands like Quaker State are much higher in paraffin wax which will coat things and build up.
Where as, if you switch to the more expensive Pennzoil Platinum Synthetic, you will have much lower wax content as it's is an engineered oil molecule and it doesn't need the same wax additives.
The challenge is you either have to know serious oil gurus who follow all the oils and oil designations and additive packages or be an oil guru to know which oil has what and how much etc.
Anyways, I would suspect you have been using high wax oils in your car and it naturally builds up on surfaces over time.
Also a browning of the metal is normal. The metal will only be a nice grey after a hot tank. It's when it becomes a thick solid almost black coating that you might be concerned.
The following pic is a normal and clean valve train with normal discoloration. Absolutely nothing wrong with this valve train:
This next picture is a serious problem with buildup/sludge and is definitely something to be concerned about:
Pictures added for future searchers of what is good and what is bad.
What brand oil are you using in your cars. Brands like Quaker State are much higher in paraffin wax which will coat things and build up.
The paraffin wax myth is a half-truth which has no basis in realty today with regard to brand name API-ILSAC licensed motor oil.
See also:
Originally Posted by G-MAN
"In the very early days of refining technology, when motor oil had no additives, ALL oil caused sludge. It was an accepted fact and there were various ways of dealing with it (like flushing the crankcase out with kerosene at every oil change). Before oil was discovered in Texas and other parts of the US, the oil fields in PA, NY, OH, and WV were the sole producers. The oil from these fields was paraffin rich, and it was known from the late 19th century that this oil exhibited superior lubricating properties for machinery. Just about the time the car and motorcycle craze hit its stride in the US, oil was discovered in Texas. But it was immediately apparent this stuff was vastly different from the "Pennsylvania Grade" crude Standard and what few independents there were had been refining and selling. The Texas crude was highly naphthenic, which means its inherent solvency was better than the paraffin rich Penn Grade crude. So...
(Those of you who have a basic understanding of how motor oil works at the molecular level should already see where this story is going.)
Once motor oil started being refined from this naphthenic crude mechanics began to notice that the sludge level was generally less and the sludge was somewhat easier to flush out. This was due to the inherent higher solvency of the naphthenic crude because the oil had more polar and aromatic content than oil refined from Penn Grade crude. By now the Standard Oil Trust had been broken up and the oil companies that refined nothing but Texas crude began to advertise their motor oil as less sludge prone than oil made from Penn Grade. (See my previous post with the old Gulf ad.) The prime candidates for targeting such ads were the larger oil companies that made a point of advertising that their oils were made with only Penn Grade crude: Pennzoil, Quaker State, Penzbest (Kendall), and Valvoline.
So, as with most myths there is a kernel of truth in the "Pennzoil causes sludge" myth. The kernel is the fact that when refining was rudimentary and no additives were used in the finished product, ALL oil caused sludge. Once the more solvent crude from Texas began to be used by some companies to make motor oil, the sludge produced was LESS than that normally seen in engines using oil made from Pennsylvania Grade Crude. Marketing took over and this fact was used as a selling point. By the time motor oils were more or less equal in their performance capabilities (40s-50s) the marketing slogans and anecdotal stories passed between mechanics over the past quarter century were so ingrained that the oils made from Penn Grade crude continued to get a bad reputation. And as we continually see here on BITOG, the myth is still alive and well almost 100 years from its inception.
I can assure you that it's not RTV. It is a hard baked on dark brown/black deposit. I can feel it on spots I can reach with my finger on the inside of the valve cover as well. It's the same hard baked on deposit a mechanic said he could not remove with solvent. If you compare your pics to mine, your cylinder head does not have this same depositing in your engine with nearly double the mileage.
Pull the valve cover off and prove me wrong
I also run the cheap thick stuff, rotella, for the first few oil changes. (I can run thick stuff here in summer without any problems 10w40 rotella convent in 3.78 qts) I think the motor was still warm in my pictures which is why mine has a nice oil coating.
I would but I just had the 30k valve adjustment done last week. Brand new valve cover gasket. If it were not for that I'd be tempted to pull the valve cover off for you.
I would but I just had the 30k valve adjustment done last week. Brand new valve cover gasket. If it were not for that I'd be tempted to pull the valve cover off for you.
PM me if you ever decide to post some strong evidence. Locked for now.
This thread details it much better and actually gets into the grades of oil and the chemistry.
Non the less, the browning of your valve train is totally normal from every car I've seen.
The reason hot tanking removes it is the metal heats up allowing the pores of the metal to expand and then the caustic solvents can remove the small particles of darkened oil from the metal.
You run the vehicle and if you never let your oil to darken you would still get a gold sheen to all the metal as the metal traps small amounts of oil in it's pores. Same exact thing as seasoning a cast iron skillet so it won't rust and becomes a pretty good non stick pan without coatings.
Once you have a base, more hydrocarbons trapped in the oil can bond to the metal's surfaces and create a skin. Still perfectly normal and after 300,000 miles you will see the valve cover has a 1mm thick skin of it that you scrape off. Still nothing out of the ordinary.
If you don't like it, get your motor rebuilt every 50,000 miles so it's all torn apart and hot tanked. Then you can be proud of the only non yellow Daily Driver motor that isn't quite brand new or a fresh replacement.
D16Y8 - Dirty Valve Train?
