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Buzo
09-30-2012, 09:49 AM
I noticed this blue smog out of the tailpipe when I start my car in the mornings.
I'm sure it wasn't there before.
My father used to say that changing the valve seals may remedy the smog at start up only if the rings are in good shape, if there is a problem with the rings, then the smog will be there all the time and not only during start up.

Any other opinion?

http://imageshack.us/a/img442/1100/smog.jpg (http://imageshack.us/photo/my-images/442/smog.jpg/)

DBMaster
09-30-2012, 11:31 AM
Mine did that for a while, too. That was when using Super Tech synthetic 10W-30. Using Rotella T 5W-40 more or less resolved the issue. It is most likely your valve stem seals, as you suspect, and/or the valve guides. If changing the seals is something you can do it sure won't hurt. My rings were fine. If you blow smoke when you take off from a traffic signal or when you accelerate in top gear you might have a ring issue. I am pretty sure that these cars did have leaky seals and guides, though. I had to add at least a little oil between OCI's on my car from 1989 until 2012. The Rotella oil minimized that.

Dr_Snooz
09-30-2012, 12:11 PM
A compression test would be a good start. Follow it up with a vacuum gauge test (http://www.secondchancegarage.com/public/186.cfm) and you should be pretty close to the diagnosis.

Most likely valve guide seals though.

g.frost
09-30-2012, 08:42 PM
The tell tale puff of blue smoke at start up is usually the valve seals. Don't know how many miles on yours, but looking to what oil you use is a possible easy fix. Many high mileage oils have 'seal conditioners' (usually a dose of group V oil) or like the Rotella DBMaster mentioned. I had this problem 5-6 years ago and started putting a quart or 2 of Redline (group V) oil in at every change. It's been many years and (have to check) about 30K miles ago and the problem has gone away completely. No oil consumption, no puff of blue smoke, and original valve seals. I'm at 160K miles on the car.

DBMaster
10-01-2012, 04:56 AM
I was at 355,000 miles. The smoke went away and I was down to adding about 1/2 quart of oil every couple thousand miles. The Rotella is HDEO (Heavy Duty Engine Oil) primarily made for diesel engines, but it is approved for gas engines as well. It also contains levels of zinc comparable to high mileage motor oils.

Buzo
10-01-2012, 03:07 PM
I think I'll start by the oil change and try to find the ones you guys mentioned.
Also the vacuum gauge stuff was very interesting to read.
I'm glad I asked first, if I see an improvement after the oil change, chances are it will fix itself with the time and I don't need to mess with the valves and its adjustment. Thanks.

gp02a0083
10-02-2012, 06:01 AM
I was at 355,000 miles. The smoke went away and I was down to adding about 1/2 quart of oil every couple thousand miles. The Rotella is HDEO (Heavy Duty Engine Oil) primarily made for diesel engines, but it is approved for gas engines as well. It also contains levels of zinc comparable to high mileage motor oils.

thats why i buy the rotella oil from BJ's, i get it for $20 a case for conventional and 26$ for synthetic. Also a faulty PCV system can cause oil to be thrown up into the intake if the orifice tube on the back on the ban and or oil mist separator box is partially clogged

Buzo
10-03-2012, 08:09 AM
The oil change didn't help with the problem. Today I started my car and immediately ran to the back of the car, I saw no smog during the first 10 seconds, but then, the smog started to come out and lasted for 30 seconds and made a huge cloud. 20 seconds later there was no more smog coming out.

After that, I can do hard accelerations and I don't see any smog.

Next step is to check the PCV and related components.

I'll leave the valve seals change for the weekend...

g.frost
10-03-2012, 08:21 AM
At least for Group V oil seal conditioning, it may take a month or more for the oil to soften and condition the valve seals and stop the leaking. I'm not sure what ingredients in the Rotella performs the magic. It must be more than just a thicker oil. IT has additional detergents as well to deal with the diesel soot.

Buzo
10-03-2012, 10:56 AM
At least for Group V oil seal conditioning, it may take a month or more for the oil to soften and condition the valve seals and stop the leaking. I'm not sure what ingredients in the Rotella performs the magic. It must be more than just a thicker oil. IT has additional detergents as well to deal with the diesel soot.

Any more details on this Group V oil? Is it something I can buy at Autozone?

g.frost
10-03-2012, 12:04 PM
Group V is synthetic Ester based oil. The only oil I know for sure has a good dose of grp V is Redline oils. I believe Mutol is group V based as well. Some 'high mileage' oils will use grp V but won't say how much. If you can get 1 qt of Redline in there, it should be enough for the seal softening effect. Group 4 especially, & Group 3 Synthetics do not treat seals so well. Grp 4 can actually cause them to dry out and shrink.

ecogabriel
10-03-2012, 06:26 PM
Mine would do that smoking from time to time. If the valve seals are as hardened as the crank and cam seals that I replaced, I am surprised the smoking is no worse.
Changing valve seals is not difficult to do - I did it on my Civic a while back. Yours look like the valve stem seals are the problem; the main thing is keeping the valves from falling inside the cylinder - I stuck rope inside the cylinder through the spark plug hole and turn the engine until the pistons compressed it against the valves of the cylinder I have to work on.

gp02a0083
10-03-2012, 07:12 PM
The oil change didn't help with the problem. Today I started my car and immediately ran to the back of the car, I saw no smog during the first 10 seconds, but then, the smog started to come out and lasted for 30 seconds and made a huge cloud. 20 seconds later there was no more smog coming out.

After that, I can do hard accelerations and I don't see any smog.

Next step is to check the PCV and related components.

I'll leave the valve seals change for the weekend...

might as well replace the pcv

Rendon LX-i
10-03-2012, 07:52 PM
If it was your rings on deceleration you would create vacuum then when you accelerate you'll see a huge puff a smoke means rings

Valve stems can be the same as your creating vaccum on deceleration your sucking oil threw worn out valve stem/guides causing smoke but only happens on cold starts .which replacing em an going from there. Doing a valve adjustment

Doing a leak down test on wouldn't hurt either it will tell how healthy your valve seats ,rings an so on.

I had to diagnosis this a lot 9/10 was rings doing the deceleration test. Doing a heavy run loading the rings as well.

lostforawhile
10-03-2012, 08:12 PM
The tell tale puff of blue smoke at start up is usually the valve seals. Don't know how many miles on yours, but looking to what oil you use is a possible easy fix. Many high mileage oils have 'seal conditioners' (usually a dose of group V oil) or like the Rotella DBMaster mentioned. I had this problem 5-6 years ago and started putting a quart or 2 of Redline (group V) oil in at every change. It's been many years and (have to check) about 30K miles ago and the problem has gone away completely. No oil consumption, no puff of blue smoke, and original valve seals. I'm at 160K miles on the car.

the chance is the valve stem seals are gone, it's not hard to fix, they have a tendency to complete disintegrate on the exhaust valves, I know there wasn't much left of mine, if you use the rope trick which is feeding a length of nylon rope into the spark plug hole, then bringing the piston up on compression, you wont have to use a compressor and air holding tool, I prefer this trick myself, you just need a valve spring compressing tool, the type that works with the head in place. it's also a good idea to cover the oil return holes in the head while removing the keepers, unless you want the fun of pulling the oil pan to retrieve one, the seal conditioning stuff doesn't work if most of the seal is long gone and turned to carbon, no point in snake oil treatments when the issue can be permanently fixed in a few hours on a weekend

g.frost
10-03-2012, 10:53 PM
If my valve seals ever start leaking again, I'll have to fix them. So far 25 years 160K miles on original, the engine is running great. I really didn't expect the Redline to solve the problem long term, but that was 6+ years and 30K miles ago.... I have no idea if it will solve Buzo's problem, just reporting my experience.

lostforawhile
10-04-2012, 02:25 AM
If my valve seals ever start leaking again, I'll have to fix them. So far 25 years 160K miles on original, the engine is running great. I really didn't expect the Redline to solve the problem long term, but that was 6+ years and 30K miles ago.... I have no idea if it will solve Buzo's problem, just reporting my experience.

the problem with the seals is it isn't just a matter of softening the seal, there is nothing left of the seals most of the time, mine were so carbonized on the exhaust side, they would turn to dust by touching them, it's a pretty simple procedure to replace them, it just takes some time is all

g.frost
10-04-2012, 07:17 AM
Today we now know what crap oils the SF/SG grades of the late '80s were. Group V synthetic is not 'snake oil'. Ring packs clogged up and failed with carbon deposits are caused by poorly formulated oils as well. It may very well be too late for Buzo's valve seals to be saved. I'll be sure to report back if and when my valve seals ever fail.
My car is relatively low mileage too, but still 24 years old.

Edit: checked my records, I started putting Redline in for the startup blue smoke in Nov. 2004.

lostforawhile
10-04-2012, 05:17 PM
Today we now know what crap oils the SF/SG grades of the late '80s were. Group V synthetic is not 'snake oil'. Ring packs clogged up and failed with carbon deposits are caused by poorly formulated oils as well. It may very well be too late for Buzo's valve seals to be saved. I'll be sure to report back if and when my valve seals ever fail.
My car is relatively low mileage too, but still 24 years old.

Edit: checked my records, I started putting Redline in for the startup blue smoke in Nov. 2004.

I'm just saying why not just fix them in the first place and not worry about it? these cars run pretty high cylinder head temps anyway, just due to design, because of the emissions, so they are not good to stem seals

Vanilla Sky
10-04-2012, 05:37 PM
I'm with g.frost. I've had these issues cleared up with changing to a high quality group V oil. Group V oils are great seal conditioners, and they tend to clean deposits well. I've seen plenty of gummed up A20 heads. In some cases, a good engine cleaning is all that's needed.

g.frost
10-04-2012, 05:54 PM
The reason I don't replace mine is there is nothing wrong with them. it's been 8 years since I saw any blue smoke and zero oil consumption, no blowby, PCV stays clean, runs great.

I would be curious to see if it would fix Buzo's cloud of blue smoke, but I wouldn't argue if he decides to go ahead and replace them. It's a cheap test to see if it works.

If Redline wasn't so expensive I would run it straight. I've been running 1qt 5W30 Redline to 3qts 5W30 Penzoil Platinum most of the time. It has really cleaned up under the valve cover too.

Vanilla Sky
10-04-2012, 06:03 PM
The PP itself is decent oil. It's my go-to oil.

g.frost
10-04-2012, 06:14 PM
I started using PP (5W30) in Nov 2004 when we got a 2005 Civic. I decided this one will only see synthetic oil. Now at 106K miles it still looks brand new under the valve cover. These oils are much better than what we had in '88. My old Accord took a bit of abuse before I woke up & cleaned it out.

Vanilla Sky
10-04-2012, 06:26 PM
Any of today's oil is better than the best oils from the 80's, outside of the then very expensive synthetics.

Buzo
10-04-2012, 06:56 PM
Since I am a "tester" with lots of spare time, I think I am going to remove the valve cover and try to visually inspect the valve seals. If I can learn something from there I will proceed to change them. My car is 200k, by the way.

The reason I just don't change them is because I am afraid I can not adjust the valves properly. I recall one experience some years ago with an old Ford F100, I ended up hiring a mechanic to make the valve adjust for me because I just couldn't make it work -I left them either too noisy or too tightened.

g.frost
10-04-2012, 07:02 PM
I don't think you can do a 'visual inspection' on the valve seals without actually taking them out. Precise valve adjustment is a good skill to learn; these motors run smooth with a good valve adjust. I think there is a good 'how-to' somewhere here. I don't trust most shop mechanics to take the time to set them just right. You have to be a bit anal about it...

Edit: rather than open the valve cover for a look, Download the service manual here, and go over the procedures to remove the rocker arms and replace the seals. See if you are comfortable and up to it, and get the tools you will need.

Vanilla Sky
10-04-2012, 07:31 PM
Dude, if you know how to put together a MS, you can do this. These valve trains are very easy to set up right. With a manual in front of you, I bet you'll have it knocked out in an afternoon.

lostforawhile
10-05-2012, 03:31 AM
adjusting the valves is very basic on this car,much easier then a lot of other cars, go over the procedure in the book, any questions ask away. the entire rocker assembly unbolts in one piece making it very easy to do the seals,

MessyHonda
10-05-2012, 08:10 AM
yeah just have a buddy or someone help you out to do the adjustments. I did a cam swap on my a20 and it was very easy. its not hard at all if you have the right tools. a flat head. and the feeler gauge

g.frost
10-05-2012, 08:29 AM
Well, geez, while you're getting the tools and help together to change the valve seals, spend $10 to put a qt. of Redline in just to see if it clears up the problem. At least it will help to clean up the ring pack and 200k miles of burned oil deposits in the rest of the engine.

DBMaster
10-05-2012, 09:44 AM
yeah just have a buddy or someone help you out to do the adjustments. I did a cam swap on my a20 and it was very easy. its not hard at all if you have the right tools. a flat head. and the feeler gauge

Don't forget about a 12mm wrench, preferably box end.

Buzo
10-05-2012, 11:19 AM
Well, geez, while you're getting the tools and help together to change the valve seals, spend $10 to put a qt. of Redline in just to see if it clears up the problem. At least it will help to clean up the ring pack and 200k miles of burned oil deposits in the rest of the engine.

Actually, this morning I fired the car up exactly when my daughter was coming out of the house (she took the picture in the bottom of this thread, so she knows how to spot a cloud of smog haha). Since my car is tinted I couldn't see anything though the windows, then I asked her, Is there any smog? And she said no!

This is something I would need to check tomorrow, but I think the smog is gone only a few days after the oil change. I put high mileage oil this time, and I had the PEMEX oil before.

Anyway, after all the input received I am ready bet my trauma with the valve adjustment, if I had to do it.

g.frost
10-05-2012, 02:07 PM
What is the 'service grade' or any (API or other) specs on the PEMEX motor oil?
Hope your High Mileage oil change saves you some work and parts. Be sure and let us know how it goes in the coming weeks, if the problem is completely gone or not. Thanks and good luck.

Dr_Snooz
10-05-2012, 08:07 PM
The reason I just don't change them is because I am afraid I can not adjust the valves properly. I recall one experience some years ago with an old Ford F100, I ended up hiring a mechanic to make the valve adjust for me because I just couldn't make it work -I left them either too noisy or too tightened.

I feel like you about adjusting valves. Most of wrenching is very linear, binary and mathematical. You turn the bolt till the torque wrench clicks, look for a specific voltage on the voltmeter, replace the part when it goes out of spec. Valves are not that way. They are all about "feel." It's more art than science. First, the feeler gauge has to be inserted perfectly perpendicular to the tappet. If you get it in crooked, you won't get an accurate reading. I bought the V-shaped feeler gauges to help with this because things are tight in the engine bay. The valve lash tolerance range usually includes three possible feeler gauges. I always use the middle most gauge and adjust the valves fairly tight because it drives me crazy when they make a lot of noise. When I'm done, I slip the other two gauges in there to see how they feel. If the one won't go in and the other slops around, then I know I nailed it. Also, keep the screwdriver steady while you tighten the locknut or you will get things way, way, way far off.

Good luck.

Buzo
10-06-2012, 11:47 AM
This is the whole story:

Several months ago I got a leak through the dizzy's hole. I had put a seal to plug the hole but it got broken with the time (I don't have the dizzy anymore because my MS handles the timing).

When I realized I had the leak, it had lost around 2 quarters of oil already. I just added the 2 quarters and a new filter and felt like If I had made the oil change. But in reality the new oil got diluted with the old oil. A few months later, I got this smog.

Fortunately, it disappeared itself just by properly changing the oil. I have no more smog as I could prove it myself this morning! Here is one more reason to love these cars!!!

When I was preparing everything to do the valves, I though in measuring the gap of each valve before removing anything, and then adjust to the same gap after changing the seals. I'm going to save that idea for the future.

g.frost
10-07-2012, 02:35 PM
Be mindful of the oil quality you use as well. Not sure what API ratings, if any, PEMEX has. You would likely be safe to stick with a major oil brand 'high mileage' oil.

DBMaster
10-09-2012, 12:15 PM
To expand on something Dr Snooz said, I used to use the middle feeler gauge (i.e. using a .006 on the intake valves because the spec is .005-.007). I bought myself a set of "Go-No-Go" feeler gauges. There is a .005-.007 and a .010-.012 in the set. With these gauges you just go for a decently firm drag on the gauge and you're good. Takes a lot of the guesswork out of the adjustment process.

Buzo
10-09-2012, 05:26 PM
Be mindful of the oil quality you use as well. Not sure what API ratings, if any, PEMEX has. You would likely be safe to stick with a major oil brand 'high mileage' oil.

I haven't had chance to stop by the gas station and look for the API information of the oil bottles. But whatever, I put new oil over old oil, regardless of the rating it was, it did a very basic mistake.

I'll keep in mind the valve adjusting procedure. I just noticed something. If my car starts up right away, at the first try, there is absolutely no smog, but if I make it backfire, then the smog is back. I believe the back pressure is getting into the valve cover through the blow-by hose and pushing the oil inside the combustion chamber.

Dr_Snooz
10-09-2012, 06:28 PM
If you had an oil starvation event, then I would be thinking rings. If so, then you'll probably get smoke under load. A compression, leak down and vacuum gauge test are in order at this point.

Buzo
10-09-2012, 06:45 PM
If you had an oil starvation event, then I would be thinking rings. If so, then you'll probably get smoke under load. A compression, leak down and vacuum gauge test are in order at this point.

Oh shut. I'll proceed to test further then.

g.frost
10-09-2012, 07:39 PM
................If my car starts up right away, at the first try, there is absolutely no smog, but if I make it backfire, then the smog is back.............

What's causing the 'backfire' problem? Ignition timing? I've never had a backfire in 25 years with this car.

Buzo
04-26-2013, 12:24 PM
What's causing the 'backfire' problem? Ignition timing? I've never had a backfire in 25 years with this car.

I removed the dizzy and put a 32 teeth wheel and a hall sensor. Since then, backfire is my second name.

Just wanted to update this thread, I changed the valve seals and the smog is still there. I foresee an overhaul some day in the near future.

gp02a0083
04-26-2013, 06:51 PM
i had an issue a while back that made me think it was the stem seals. In my case they did need replacement but what i found out is that the PCV system was not able to breathe correctly and somehow throwing oil into the intake. It ended up the oil pan i had had nearly blocked the breather port.

Buzo
04-26-2013, 07:41 PM
i had an issue a while back that made me think it was the stem seals. In my case they did need replacement but what i found out is that the PCV system was not able to breathe correctly and somehow throwing oil into the intake. It ended up the oil pan i had had nearly blocked the breather port.

Good! I bought the PCV the same day I bought the valves. I'll change it at the first chance.