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sometimes smokey but not all the time...

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Jer

Jer

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About 2 weeks ago when I was leaving work at the end of the day Midge smoked (oil smoke - not antifreeze smoke) when I started her up, then no smoke for rest of the drive... thought maybe it was a valve seal leaking... then I park for the night, start the next day - no smoke, which contradics valve seal as they are usually consistant with smoking after every shutdown/startup cycle... then while driving and stopped at stop light, it starts smoking, then drive away & it clears up... yesterday when I start to go for lunch, smoke, go to leave at end of day... no smoke...

Any ideas what the issue may be ? I'm starting to wonder about the pancake PCV valve... it is one item that could be failing sporadic causing these "random smokings" as I believe valve seals/worn rings would be more consistant ? 1275 Motor was rebuilt about 6 years ago & has approx 10,000 miles on it now.
 
Not likely you would wear rings in 10K but you could have some hard valve o rings as you speculated. Or even missing ones. Take a look.
 
what do your spark plugs look like? easiest and quickest to check
 
Take a look at the hose going from the valve cover
to the air cleaner. Is there lots of oil inside?
If so its an indication that your rocker shaft is
worn. When that happens there will be LOTS of oil
in your valve cover, and in some circumstances it
can overflow and get into your carbs. Happened to me
on a Big Healey that I had rebuilt. New oil pump
provided just enough extra pressure/volume to cause
the problem. Took a long time to figure it out.
Steve
 
No hose from valve cover to air cleaner on mine, believe that was on the later models, my pcv hose is from the timing chain cover.

Okay Jack I will pull the rocker cover & take a peek, I have a set of Payen valve seals that came with my head gasket set still on the shelf...

If I need to change valve seals -Anyone know how to change the valve seals without removing the head ? I have seen it done on some ford & chevy motors, pressurize the cylinder, compress the valve spring, remove keepers etc. Not sure if anything special is needed to perform on a spridget motor ?

JP just had the plugs out recently, they were light brown identical for each cylinder, ironically I noticed this issue about 2 days later... I will pull again for fun & see what they look like now.

Thanks for the help.
 
I have had the same kind of problem with my MGB. I suspect it could have something to do with venting. I just get mad, park the darn thing and ignore it for awhile. There is always something else to do. How is that for solving a problem?
 
Paul, that's basically what I'm doing right now, just not parking it, I see it as keeping the insect population under control, allthough it's embarrasing, it's also kinda funny, I'm looking forward, not behind so it doesn't bother me to much !
 
paulsherman said:
I have had the same kind of problem with my MGB. I suspect it could have something to do with venting. I just get mad, park the darn thing and ignore it for awhile. There is always something else to do. How is that for solving a problem?
Click to expand...

Boy do i know that feeling....

m
 
In the shops, I always used air fitted to an adaptor in the plug hole.
In the field, a long piece of 1/4" nylon rope with a big knot in the end so you don't "lose" it down the hole.

Drop the piston in question, feed in the rope, run the piston up (by hand!), set the brakes and put it in reverse (block the wheels won't hurt any).
Use a compression bar suitable, depress the spring, remove the keeper, change the seal, reverse.
Do ONE valve at a time.

Dave
 
Doing valve seal work without removing the head is easy. First thing to do is to pull the plugs. Then select the cylinder where the piston is at or near the bottom of its stroke. When I did this years ago I used cotton clothes line rope but you can just use anything of that sort. Stuff as much as you can into the plug hole. Then turn the engine over by hand until it stops as the piston is as high as it will go. Your valves will now be held in place and you can do your seal replacement after you release the spring pressure. Be careful doing this. I used a screwdriver once to lever the spring and had a serious problem. The screwdriver slipped and one of the valve spring keepers flew up and hit me in the eye. It shattered my contact lens and if I hadn't been wearing a lens the doctor said I'd have been blind. It hurt like *#@*.
 
I have a bunch or various "bars" for the project, but they require being attached to something for the pivot.
I also have a screw-type, with two "fingers" that grab the spring and pull it up.

I think mine is Lisle.

Easier.
 
ahhh yes Leslie brand, I know the style your talking about - okay great thanks all for the suggestions, always good to confirm :smile: Hopefully I will be able to investigate this weekend... until then I will continue to randomly smoke out my city !
 
Sometimes, odd things happen.
I had a car in once that would smoke like all hades, then no smoke, then smoke like all hades, etc, etc, etc.

Sometimes, folks use paper shop towels to plug oil drain backs so when they "work" on something, they don't drop bits (like keepers) down the oil drainbacks.

The oil-soaked paper was there in ALL the drainback holes from the last shop that had worked on the car.

Filled up until it sucked it down past the stems, then didn't smoke for a while.

One clue was the oil level dropped over a quart when you started it, and took 30 minutes to drain back.

So, the guy kept adding oil............
 
This past weekend I was trying the new valve spring compressor on my spare 1275, doing a dry run in anticipation of changing the valve seals on my car - then while bleeding the new clutch slave cylinder I noticed excess oil on the vent hole of the PCV valve... hmmm interesting, removed & noticed oil on the intake side of the PCV - I know it pulls in excess gases etc. but it shouldn't be an oil passage :smile: Looks like my replacement PCV has failed after 3 years.
I removed & plugged the port on intake & vented hose to atmosphere - and guess what? No smoke all week, it used to smoke at least once every drive, pulled the plugs & they are back to golden brown.
This weekend I will tear the PCV apart to see if I can figure out what happened. At least I can avoid the valve seal change !!
 
Whew!

Glad to learn it was something ancillary. That falls under th' heading: "It's usually th' Dumb Stuff. Don't over-think the issue." :wink:

...tho Dave's story of shop towels in the drain holes kinda made me tweak 'n twitch a mite. :eeek:
 
I had the same problem on my 1275. Happened only about 1.3 miles into my commute every morning.... at the instant the temp gauge moved. I've never figured the cause, or worried about it. There no damage being done, it's just a "curiosity" that others have noted. Usually with first generation PCV systems.

It actually helps to keep the tailgaters back a little
 
Are you sure your jets are returning all the way back to full off chock- fastidle ? my front carb would sometime hang up a little after using the choke- fast idle and when warmed up would smoke rich. A pushup on the jets by hand will verify that they are not not hanging. Just a thought.
 
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