Blue smoke every morning

Worn valve guide seals. Not uncommon, but not prone to causing any major engine-seizing damage although you are burning a little oil, and that comes with it's own set of issues. The fix isn't too tough but still isn't one I'd try unless I had at least some decent experience working on the top end of your motor.

I believe GM changed to ceramic in '90 or '91.

Cheers - Jonathan

Valve stem seals. Common in engines with miles on them. Not a real concern unless it gets REALLY bad. Fix depends on what you want done. If the engine is running good and has no other problems you could just pull the valve covers. Pull all the plugs (TAG the wires first) Turn the engine so both valves on a cylinder are closed and the crank is at BDC. Remove the rocker arms. Use an air adapter to hold the valves closed while you remove the springs and seals one at a time. Replace the seals and reinstall the springs. Reinstall the valve covers. Or pull the heads off and do a complete top end valve job. I would probably do this one as it would give you a chance to clean out the EGR passages and replace the intake gaskets and check for any other problems. Maybe change the timing chain as well.

plugged drain-back holes in the rear corners of the heads

allows oil to pool around the valve stems and run down into the cylinders

common problem with 4.3's, the holes are a lot smaller than in a 5.0 or 5.7

take off valve covers, run a 'snake' made of a piece of inner speedometer cable chucked into an electric drill down thru the holes

not a hard job, just time-consuming getting the covers off with al lthe crap in the way

My 89 was recalled in 92 to upgrade valve stem seals and they were still "rubber" but just of a different design. Like the others siad though, it is nothing to get upset about.

Not likely at all if engine has had good regular maintanace with good oil. Valve guide seals are many times more common and plugged drian hole would smoke all of the time to because oil would build up under valve covers in a matters of seconds when engine is running and it would "puff" a lot all the time.

I have to agree with TranSurgeon My 88 1500 with 125k on it had this problem and I cleaned out the return passage which eliminated the smoke problem There was also flash running from the base of the last valve on the right bank that caused pooling of the oil causing it to bake and add to the passage becoming blocked. About 6 months later the problem reoccurred . If I was going to have a valve job done I would ask to see if they couldd grind the flashing down.

Joe

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If you did have had this problem is is from poor mantainace or cheap oil or both (you had problem again too) because I have never had the problem with over a dozen small blocks I have owned of various types and some of them went close to 200K too. I have one now with a 173k that is clean as a whistle inside too.

A "dozen" small blocks! Wow...no wonder you know so much about these engines! The rest of us who actually work on cars for a living have "only" worked on "hundreds" of these engines. Why don't you give a little credit where credit is due? Both the valve seals, and the oil return holes have been problem areas with these engines. If in this case it happens to be the drain back holes...much less money is involved. If not, then it's updated valve seal time. Of course, unless a person knows the proper procedure for installing sbc valve seals, they may end up with more blue smoke then they had before.

Ian

If the engine isn't using any oil or fouling plugs is there any reason to monkey with things if all that's happening is blue smoke on morning start up?

I was 'turned in' to the state for 'polluting' by a 'conscientious citizen'. Of course that citizen had no idea how emissions testing is done by the state or what the guidelines are for a smoking engine.

Never the less I had to foot the bill on an uninformed citizens complaint.

cheap

types

How many have you owned???? And mine are properly maintained too which the ones you talk about are not and/or they have mechs that do not encourage proper maintance because it might reduce their income.

BTW, I have owned, 283?s 307?s, 327?s and several 350?s personally (and I have driven more than once Chevies old 265?s, the hot 302?s, a

400 SB with a 350 crank and regular 400 SB?s too) and owned a few big blocks too (my favorite, the 396) not counting many other non GM engines I have owned too. The only engine I ever had plug up return holes in was a bone yard engine I installed over 30 years ago that had seen poor maintance or poor oil and was crudded up badly and it took several oil change to flush it out.

You can talk tell the cows come home but they holes will not plug up if the engines are properly maintained so somebody is not doing their job here.

nope

well, since the original poster definitely did NOT state that he has owned it since it was new, you are doing your usual condemnation of someone 'not doing their job properly' while beating your chest telling everyone about your marvelous well-maintained engines.

you might try to ascertain the FACTS (how long has the OP owned it, the vehicle's history, etc, etc.) before jumping onsomebody's ass for 'not doing their job'

No reason at all really, you can let it be. (this guy also tells people to hook up tranny coolers wrong too and that detriot has been doing it wrong for years) If oil consumption is fine and plugs are good you can let it be if you want because if it was plugged up as they are trying to sell you it would be smoking more and using more oil. Valve guide seals are a VERY common problem on older chevy engines based off of the small block V8 (which the V6 is) or big block V8 too.

SnoMan can't seem to understand a simple four letter reply, heh

'snow-job' is just pissed cause I kicked his ass on a transmission cooler thread

"" wrote: > I have a '89 GMC Sierra 4.3 110k and every morning it gives a > little puff of > blue when I first start it. Is this common? Is it a concern? > What's > involved in a fix? > > Thanks, > MZ

Just to add to all the replies.I agree with the valve stem seals they are all to commen for hardening and cracking.GM only puts them on the exhaust valves only (Another GM bright idea) if you replace them put seals on the intake valves as well,the head is already cut to except seals.I would recommend using the seals with the metal band around them this way they stay firm to the head and don?t move with the tavel of the valve.Any parts store that carries Fel-Pro will have them.I think the part # is MV1880C.

And this can be done without removal of the heads.Hope this info helps.....