Burning oil - bad rings or valve seals?

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My car burns oil.
Any opinions on whether it's bad/stuck rings or leaky valve seals?

'97 Honda Civic, single-cam VTEC, 179K miles on the clock.
Burns about a quart per 1000 miles.
I keep it topped up but I'm not so sure about previous owner.
I bought it at 150K, 13 months ago.
I've done 3 clean + rinse cycles of Auto-RX and did a Seafoam treatment of the intake/valves system. Did not Seafoam the crankcase system.

Recent 'tests':

1) I drove it till well warmed up, parked it for 30 minutes and then started it. I saw no smoke out of the tailpipe.

2) I went down a good long hill with foot off the gas, in 2nd gear, at 4000 rpm. That was maybe 30 mph. At bottom of hill I gave it gas to acelerate, about 1/2 to 2/3 throttle. Saw a big blue-gray smoke cloud behind me on the right side of car where the tailpipe is.

I've heard a couple different interpretations of the downhill-in-gear test. What do you think? Bad rings or bad valve seals? I think I can handle the valve seal job but I don't want to pull the head.

I'm considering doing a compression test but I'd like to see what you folks think.
 
Most importantly, can someone try interpret the downhill-in-gear test?? Big cloud when I gave it gas. With foot off throttle there's no fuel injected so that's why the oil burned when I gave it gas on the flat after the downhill. You think oil is getting in past rings or valve seals??

Yesterday I put in Mobil 1 High Mileage 10-30. Previously used various dino oils incl. WalMart and more recently Castrol GTX.
(Honda recommends 5-30 or allows 10-30 if temps stay above 20ºF.)

I had the PCV changed about 3-4 months ago, tech said it didn't look bad once he got it out to see it.

Who makes Max Life and do you think it's better than Mobil 1 High Mileage if the seals are bad?
 
Originally Posted By: Steve S
Have you pulled off the valve cover to see how the engine was maintained ? [sludged up]


Yes - did a valve adjustment this past summer. General bronze tint but no sludge. That was after two full Auto-RX treatment cycles. Before those I did a GUNK engine flush so I hopefully got most of the worst junk out of there.
 
Sounds like dino goo on your rings, but ARx didn't cut it.

Have you tried a 10W-40, just to see if consumption slows?

Have you made sure the PCV system is working perfecttly?
 
Originally Posted By: XCELERATIONRULES
If it smokes heavily when started,then lessens,it's the seals.
If it smokes at throttle,the rings are worn.


Tomorrow in daylight I'll test giving it gas, without the high-vacuum, high-rpm coast before giving gas. I sure hope its not rings.
 
Yep, the PCV valve might be clogged (it is located next to the oil filter and you might have to remove the filter to gain enough space to swap it). Are you use you are burning oil ?

We had a 1998 Civic EX and my nephew now drives it and has approx 260K miles and does not burn a drop of oil, these engines are very easy on oil. I hope you are not using 5w20 oil cause I tried it to see if gas mileage would improve but my wife's Civic drank 5w20... switched back to 10w30 and oil consumption went away.
 
To recap -

PCV was replaced just a few months ago, and it's hose also.

Yesterday I put in Mobil 1 High Mileage 10-30. Previously used various dino oils, 5-30 only till now.
(Honda recommends 5-30 and allows 10-30 if temps stay above 20ºF.)

I didn't yet do a compression test - maybe this week after work one night.

Honda message boards seem to report Hondas sometimes burning no oil, others burning it as much as mine. VTEC's seem more inclined to burn oil but certainly burning 1 qt/1000 mi. is not part of the original design intent.
 
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High vacuum will pull the oil across the intake valve guides as easily as it pulls the oil across the rings.

If the engine burns less oil right after an oil change then it could be a fuel dilution problem. I have an engine that plumed for 20 minutes after a cold startup. After an oil change the smoke went to a barely noticeable puff on cold startup. The new oil was not ruined because I was already working the combustion side with gas additives.
 
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take a compression test of all the cylinders get the reading and then squirt some oil in the cylinders one at a time and take the compression test again if its the rings it will show it in the reading meaning if you get a higher reading its the rings.. oil will seal the rings and make the reading on your compression tester show a higher reading
more so than the valve guides
 
Originally Posted By: LT4 Vette
Do a compression test.

That Vtech (lean burn) engine is soooo easy on oil. I would not worry about 1 quart per 1K miles.
+

He-heh. It only holds about 3.5 qt! 1/2 qt between the dipstick marks! I have to check it often to keep it up there. Thanks for the kind words though!
 
Originally Posted By: LT4 Vette
BTW,

what is your gas mileage with your HX ?


Ah, that's the sweet part.
Generally about 42-44 mpg on east coast RFG type fuel with 10% ethanol. In winter with winter fuel and worse conditions in general, high 30's mpg's. My driving is about 60/40 highway vs. 2-lane state roads. Not much in-town driving.

But we're getting off topic. As much fun as that is.
 
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Compression test question:

Compression test procedure as I've seen in a couple writeups
REQUIRES WARMED UP ENGINE.

However I've been told to NEVER remove spark plugs from a hot engine with aluminum head - can damage the threads in head.

So??? What's the deal here? Which way to go? Sorta warm engine but not hot??
 
Looks like you've done all you can without tearing her apart, so run the Mobil HM for 1000 miles and report back.
 
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