Exhaust smoke

[Anonymous]

This is another smoking/non-smoking situation. I have a '67 coupe with 200" motor, bone stock, and no history except the seller's sales pitch. I see blue/gray smoke heaviest at idle when there's more vacuum. I drive it almost daily. Number 5 and 6 spark plugs get coated with the oily crusties, and #4 gets a little oily. The previous owner said it sat in her garage, but she drove it around her property once in a while. Considering the lay of her land, I'd guess she never got over 15 MPH and probably ran it less than a half hour. Could this cause the valve stem seals to dry up.? Short of tearing it down, is there a way to tell whether it's more likely to be rings, or some problem in the head (not mine, the car's)?
I am trying to baby it along a few months while I get another motor ready to install.

 

[Anonymous]

I could very well be the valve stem seals that are causing the problem. I was going through about 1 quart of oil a week just going back and forth to work. It did seem to smoke more at idle and take off after idling. I finally pulled my valve cover and discovered that I had 4 valve stem seals that were badly cracked and 2 that were completly gone. All of the seals were very brittle.
My car had set in a garage for 15 years before I bought it.

Its worth a look and valve cover gaskets are cheep.

-Brian

 

[Anonymous]

so are the valve seals...its just a bitch to put in (so I heard...I paid to get it done)

 

[mugsy]

The #5 intake valve seal was shot when I bought my '65 Mustang. The plug would foul in about 100 miles of driving . Replaced them and then went to solve other problems. 8)

As suggested, take the valve cover off and poke/move the valve seals. They should be ply-able. If they are hard and/or brittle then they are more than likely the cause of the problem .

I replaced the seals on my car with the head still on the car. Its not bad IF you have an air compressor. All you will need to buy is a valve spring compressor that compresses the spring from one side. Most valve spring compressors require the head to be removed. I replaced all of the seals in about 2-3 hours. Actually did it in the parking lot of the glass plant I was working at one saturday!!! 8)

 

[Michael Mc]

Mugsy, ya work at the McGraw plant? I grew up on Smart street, right near the northwest end of the complex where the railroad comes into the place (or used to come in). 8)

 

[mugsy]

Actually work for the old LOF at the time. Now its Pilkington who owns them. I bought the car in NC when I was down there on a project and did the fix in the parking lot next to the main glass plant.

I know a little about the McGraw plant, it just over the border in Detroit. But have never been there. Its a Chrysler autotive fabrication plant. Most of my work was in "float" glass plants. That's where they burn the sand into the stock sheets of glass. Now I work for another glass company and have spent the last six moths in Fresno!!!

tanx,
Mugsy

 

[trashline]

do a compression test on each cylinder

 

[MercuryMarc]

I changed my valve stem seals without compressed air using the "rope trick," and , no, I am not a professional cowboy.
After you have removed the valve cover and are ready to compress the spings-
1. Remove one spark plug (one cylinder at a time)
2. Rotate the engine until the piston of the open cylinder is as high as it can go (look with a flashlight down the open pulg hole).
3. Jam as much 1/4 inch diameter rope as it takes to fill up the cylinder (I used a wooden dowel just a shade narrower than the plug hole to help push in the rope). Make sure to leave one end out of the plug hole so you can pull out the rope when you are done.
4. Now you can release the valve on that cylinder (you need the 10 dollar valve compression tool from Kragen or NAPA, etc.). The rope keeps the valves from falling into the cylinders when you remove the spring.
5. After you've changed the rubber seal, then reattach the valve stem, spring, keepers, etc, you can pull out the rope and replace the plug.
6. Do the same for each cylinder - making sure to move the piston up to the top for each cylinder.
I am told that any rope strands get burned up after restarting.

I did it this way without any problems.

Good Luck.

Marc in SF
63 Comet
69 200/C4
http://mercurycomet.net

 

[trashline]

use a nylon rope. less fiberous. burn the ends a bit so they dont frey. that is a cool little trick

 

[Anonymous]

Thanks to all for the good advice on valve stem seals. I used the rope trick. It took me about 4.5 hours to do all 12 seals, but I was a little slow due to having a bad cold. Actually it was the Nyquil (12% alcohol). I did it with the head still on the motor. I recommend covering the pushrod holes just in case a valve lock goes astray or if you're all thumbs like me.
I am wondering about a tip I heard about. A guy told me that a few ounces of brake fluid in the oil keeps the rubber seals pliable. Anybody ever heard of this??

 

[MercuryMarc]

Glad it worked!

I forgot to mention that I was one valve keeper short when I finished so I had to buy another.
I am not sure if it went down a rocker hole or on my garage floor. I crossed my fingers and the car started fine. I never diid find the critter.

Let us know if the car burns less oil. Were the seals in bad shape (hopefully they were rotten and all your problems are solved...)?

marc in SF
63 Comet
69 200/C4 (78 200 in my garage, ready to swap this winter)
Dual Cupholders
http://mercurycomet.net

 

[Anonymous]

I can't say I heard about using brake fluid, but I have heard about adding some trans fluid to the oil to keep the seals pliable, especially during storage.

 

[Anonymous]

My seals were very hard. There was absolutely no flex at all. I haven't given it the true test yet. The worst smoking was after driving on the freeway for about 20 minutes or so. Still need to do a compression test. I found a bent pushrod. A big dogleg bend about two inches below the rocker arm. Don't know how it happened. I was wondering how loose the valve stem is allowed to be in the guide? I could move mine side to side but very little--could barely see movement with real strong reading glasses on under bright light. Seems to me they couldn't be real snug or you'd have too much friction, but I'm still learning. The seller had a lot of reciepts but not for engine work and claimed she had spent big bucks on maintaining the thing. My advice to everyone is not to trust a private seller any more than a used car sales person. I don't think $2700 for a '67 coupe with great interior and pretty straight body is too bad though, especially here in the northwest land o' rust.

 

[Anonymous]

sounds like a nice price. do you have any pictures?

you probably would have wanted to do the engine once over anyways....

where in the North East?

 

[Anonymous]

I live in the northwest--Camas, Wa. I call it land o' rust because I got spoiled with nearly perfect weather in southern Cal (San Diego). After 26 years I'm still not used to 8 straight months of rain in most years. I don't have pics to post. Ford says it's pebble beige and saddle interior, but I call it two shades of tan. My wife's is a yellow '66 coupe I6 w/C4 and working original factory A/C. A birthday present from me 9 years ago. I called it Spongebob one time only. She gave me that look and reminded me she never did like yellow cars, so I shut up and went out and waxed it to make points. Dont' know which is harder to figure out--automotive electrical problems or women???

 

[Anonymous]

LOL women vs electrical problems

they both can short circuit so easily

sorry, I read North East. My bad

I like the two tone tan-ish scheme