1990 Prelude Si ALB

Greetings to the wealth of Honda knowledge! ;-)
I have the aforementioned car; B21A1 engine, 5spd. It burns oil like a 2-cycle engine. (Seriously, I have to put in a quart every 400 miles or
so) I read on Wikipedia where this particular engine has cylinder sleeves made with FRM, which tears up piston rings. While it seems like I should just accept that, I don't believe everything on Wikipedia to be 100% accurate, 100% of the time. My dad suggested that since my car has plenty of power, both torque and horsepower, it could just need a valve job to stop the oil burning. Is there a way to tell without tearing the engine apart and looking? Someone told me that one way to tell is to start the car, let it idle for 5 minutes, shut it off for 5 minutes, then start it back up. If it immediately puffs smoke out of the exhaust pipe, it's the valves. If it doesn't, it's the piston rings. How accurate is this? Any other ideas? Last of all, how much does the average piston-ring-replacement cost?
Thanks in advance! :-)
Jonathan
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Jonathan wrote:

=================================== Here's a cheap idea: Check to see if your PCV is stuck open, sucking your oil vapor out of the engine. Always check the most obvious things first.
'Curly'
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Jonathan wrote:

given the comment stating "These sleeves are so strong that they often do not lose their factory cross-hatching marks after 200,000 miles!", i'd do some more homework before accepting the rest of that commentary. i don't know what the sleeve composition of your motor is, but i can tell you that there are /many/ hondas that don't lose their cross-hatching after somewhat higher mileage than that, and they're only cast iron.

sure, i can tell you right now - replacing valves won't stop your oil burning. maybe replacing the valve seals will, but valve stem loss is relatively minor. on the old days, valve stems never even had seals.

maybe, maybe not. unreliable.

look for the gotchas before you do any serious work - as curly says, a defective pcv valve will have you drinking oil most impressively. other factors include incorrect ignition timing [too hot combustion temperature causes excess evaporation], leaks [obviously], and excess fuel [dilutes oil film on cylinder walls]. if you address all the above, and you have low compression, go ahead and do the rings, but make sure you're dead certain about the ring material. if it is indeed a composite, you may be forced to stick with the original honing, but as a general rule, you always have to re-hone otherwise the new rings never bed in properly and the motor will forever burn oil by the gallon.
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I definitely agree with that. I regard Wikipedia as the world's largest repository of completely unvetted information. It can give very good starting points for research, though.
My dad suggested that since my car has

The smoke indicator has mostly gone by the wayside since the catalytic converter also burns smoke once it gets going. 5 minutes of running is long enough to make it likely that the converter will suppress the smoke. A better indication of bad valve seals is a puff of smoke on startup; same concept, but with a cold converter. Caveat: a bad PCV valve can cause the same indication.
As 'jim beam' points out, that is a smoke source rather than a place for oil to disappear. We've seen several reports of oil consumption in your range, even in relatively new Hondas. The only ones I know of that were tracked down by tenacious service departments were from a broken ring in one cylinder. Repair in an older engine would be essentially an overhaul, because of the number of wear items that should be replaced if you are going to have the engine open that much. A replacement "jdm" engine is usually a cheaper approach.
You don't mention smoke, which is consistent with the converter burning it off as it should. If your only symptom is that you have to top off the oil every time you fill the tank, it may be your most reasonable way of dealing with it - carry oil.
Mike
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Michael Pardee wrote:

Mike,
Thanks to you [AND EVERYONE ELSE] for your input!
Well, I have been carrying oil in my car, by the case, as a matter of fact. I have noticed this though: I start the car, back out of my driveway, and then as soon as I shift to 1st and proceed forward, I can look in my rearview mirror and see a small cloud of blue smoke. The weird part is, it's just a cloud, not a trail. I see smoke sometimes when I get on the gas going down the interstate, but I figure that's just the build-up from the catalytic converter getting blown out. (The smoke appears to be brownish, not blue or gray, and typically appears once the RPMs hit around 5k or more) I've had a friend ride behind me and asked him to look for blue smoke, and he said he hasn't seen any. (I even asked him to make sure the smoke I see when I gun the gas isn't blue, and he said it isn't) Now, time for my ignorance to totally shine: Where exactly is the PCV valve located on a Prelude? (I would generally be able find this out myself, because I usually purchase a Haynes manual for every car I own; but believe it or not, there is no Haynes manual for my car. I checked with both Advance Auto and AutoZone, and they said that they can't even order one. It doesn't even exist) Also, how do you tell if a PCV valve is bad?
Thanx again!
Jonathan
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Jonathan wrote:

do NOT waste your money on a haynes manual - utter utter garbage. go to helm.com and buy the factory honda workshop manual - the best tool you could ever buy for that vehicle.
regarding smoke, oil is generally "blue", excess gas when cold is black, excess gas when gunning it on the freeway is brown.
don't waste time trying to test the pcv valve - just replace it. it's cheap and the new one is guaranteed to work properly.
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