Clear the smoke

[abarth69]

Had a look yesterday at the wifes smoken 1275 engine.Still have not made up my mind on what to do next. We ran another compression test dry at 175 lbs on all 4.Wet test showed was 193 on all 4.

So I think the rings are bad do I have this right?????


Mark

 

[Billm]

To me it sounds like your smog system is causing the smoke. Make sure that your PCV system is working properly before you do much other engine work.
Bill

 

[Pythias]

The question becomes.. does it smoke on acceleration, or deceleration?... .. Decel = valves, Accel = rings. both, = engine refresh.

 

[RonMacPherson]

Depends....


Was the engine hot, or at least warm when you did the compression test?

Were all four plugs removed when checking compression? Was the throttle opened(jammed full open) when cranking the engine? Did you crank the same number of revolutions for each cylinder(6-8)? How much oil was added? Should be appx. 1 tablespoon or three or less squirts with the old time engineer oil can.

If the engine was cold and lots of oil I would not condemn the rings without further diagnosis.

Either a cylinder leakage test, which can pinpoint combustion pressure leakage, or get a can of GM top end cleaner. with the engine running suck it through the carburetor, at a high idle, intermittently revving the engine to 2-3K range to inhale the top end cleaner without hydrolocking the engine. After the can is completely empty, let it sit overnight. Start it up the next morning, prepared for LOTS of smoke from the exhaust. Then go for a drive to get it warm and recheck your compression...

 

[abarth69]

Stone Cold

All the plugs out foot on throttle opened 6-8 turns and a couple of squirts.
Just can not get over the fact we went from not to bad to really bad in such a short time. Pulling the engine and doing a rebuild was not in the cards this winter.

Come hexx or high water I must finish my 1959 Fiat Abarth Double Bubble it's only been in the works since 1980. Next year I want to troll for some of those Bugeye's

Cheers

Mark

 

[RonMacPherson]

That's why I recommend the GM top end cleaner. It may just be carbon buildup on the rings. And it's a lot cheaper diagnosis tool, possible problem resolution than having to tear the whole thing apart.

 

[tosoutherncars]

I'll apologize in advance for the silly questions...

It is grey-blue smoke you're seeing?

It was asked earlier, but I'm not sure whether the answer has come out. Is it smoking most noticeably on accelleration? Or on the overrun (engine braking)?

 

[abarth69]

O it's Blue

Even smokes just bit while at idle crack the throttle and you get lots.

Mark

 

[startech47]

A bad oil ring will not affect the compression readings.

 

[tosoutherncars]

Back to Bill's original question... you're sure your PVC system is OK?

 

[jhorton3]

It could be oil vapor being sucked into the intake through a malfunctioning PCV system. From my experience though it takes a little while for the oil to warm up and atomize, then it gets sucked in and causes the fog. If it's happening right from start up it could be the seals on the valves have perished.

 

[abarth69]

I have all the pcv stuff off the car. Going to try the GM magic in a bottle.

Mark

 

[abarth69]

Well pulled the engine since the season is almost over in Ontario. Took the head off and there seems to be oil going down the guides. There is also some marks in one of the bores. Have to take the bottom end apart yet.

Cheers

Mark