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Bluish gray exhaust?

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OregonTR4A

OregonTR4A

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When I high rev at idle I get a little bluish gray smoke out of the exhaust. I have only noticed a little while driving. Can anybody tell me what this indicates, if anything? I also noticed a slight oily film on the back of the car while washing it.

Thanks
 
rings. type to renew the bottom end.

(edit)If there's oil on the back of the car, I doubt it's just worn valve guides. Worn guides give a puff of smoke at startup because of the oil draining past the guides into the head. Then it goes away, mostly.

But if the smoke is at higher rpms and consistant, probably worn rings. A compression test will tell.

How many miles on the engine? What oil are you using? You could also try an oil emulsifier like Lucas temporarily, until you get it fixed.
 
If you get the blue smoke all the time its piston ring replacement time, and main/rod bearings while you are in there.

If it only smokes briefly when you first rev the engine (as in when pulling away after idling for a while) then it's likely oil leaking past the valve stems in the head.

Easy way to check is with a compression test on each cylinder, do it dry and record the readings then a small quirt of oil in each cylinder redo the test and see if the readings come up significantly, if they do then it's rings.

Either way it's work but quite do it yourself. If you need the comp test procedure just ask.
 
It sounds like it is probably the valves as it only smokes a little after idling for a while. I will do a compression test to verify. Thanks for the replies.
 
YankeeTR said:
drive it and don't worry about it...it's an old car...
Click to expand...

My sentiments exactly. When it gets so bad it pisses off the motorcyclists behind then it's time for a rebuild!
 
OK...this is the first time I have <u>ever</u> promoted this stuff and I'm going to open a major debate when I post...I don't work for these guys...and I don't get any kickbacks...I found them several years ago by surfing the net....tried them and it honestly worked in my situation...I had an old smoker 6 cylinder...like a freight train...I figured what do I have to lose but a few bucks...if it works it saves me a major rebuild, which I couldn't afford,..didn't want to do myself...and I had only planned on keeping the car for 1 year more anyway....did what they said.. drained out the old oil...I didn't flush it out but it is recommended...put on a new filter, refilled it with the FHS oil and I swear on the kids...an immediate major reduction in oil burning on the first drive...only smoked when I got down hard on it....ran it for a month...and figured what the heck...did it again...new filter...fresh FHS...it has now been smoke free for 3 years (I just made sure to put nothing but FHS in it)never spent a dime on rebuild yet just the oil...it isn't cheap runs about $12.00 a quart plus shipping but I have to be honest it is well worth the try....compared to a rebuild or just putting up with a smoke trail...

Here's where I hear there's NO SUCH THING AS A SMOKELESS MOTOR OIL...and I said it all the years growing up until the day I tried this stuff...and I still can't believe they are not known worldwide for this stuff..I even sent them a testimonial which to-date is posted on their website with many others.....they are known however for their outstanding racing formula's...it's your call...here's the website:

https://members.aol.com/FHSoil/SmokeLess.html

I don't know if it works in every case but it did in mine...Should you try it I would be excited to know your results and I'm sure as well as ...what is it now 8001 other BCF'ers...

Just an added note..it doesn't help anything regarding leaks...
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Wonder how much ZDDP it has. [/QUOTE]Shawn sorry..everybody would expect me to do it...I can't resist...

I don't know...how much does a ZDD...p?
Matter of fact I don't even know what a ZDD is?

update 8/24/2007: <span style="color: #3366FF">OK..I'm back to serious now...but agree if it's minor who cares...my situation as I commented was a freight train...and it definitiely needs a rebuild but since this stuff is working I figure it can't do much more damage than a complete rebuild..so I'll put off the inevitable..</span>
 
YankeeTR said:
drive it and don't worry about it...it's an old car...
Click to expand...

You know, I have to say that I agree. I just had the extreme pleasure of spending the weekend with my dad at the Pebble Beach Concours d'Elegance (he had a 1937 AC sports tourer showing there), and I noticed that a huge percentage of the outrageous automobiles on the field smoked -- they either burned oil, ran way too rich, etc. And these were serious cars. But they're *old* cars. I figure if an Aston Martin DB3S, a 1934 Duesenberg Boattail Speedster or a Talbot Lago aero coupe can burn a wee bit of oil or run a bit rich, so can my LBCs. Unless you've clearly got a serious problem, drive it, and have fun. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
BIBBER said:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Wonder how much ZDDP it has.
Click to expand...
Shawn sorry..everybody would expect me to do it...I can't resist...

I don't know...how much does a ZDD...p?
Matter of fact I don't even know what a ZDD is?[/QUOTE]

hehehe, which is why I put the "wink" in there. Just trying to beat a dead horse a little more...
 
the great CARNAC was consulted and found everything one would not want to know in a Funk & Wagnell's 3rd Edition, kept in a mayonaise jar on a shelf hidden from site for three years...but now the answer is known...ZDDP:

(may your sister run into a low flying YAK!)
https://www.ttalk.info/Zddp.htm

some of us remember Johnny Carson! don't we?
 
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