Engine burning oil

[cgates30]

I have a '74 that has started burning oil. I know this sounds basic, but how do I assess what needs to be done? It's a whitish/grey smoke and seems to get worse as the engine warms up while the car is being driven. I've adjusted the distributor to minimize the smoke and the carb was replaced a couple of years ago. 

 

It seems like valve guide/head rebuild comes up frequently in my searches. I have come across another head. It's a 1.8i head with the injector ports already filled, however, the combustion chamber on cylinder one looks a little chewed up around the flat part.

 

Is the head replacement a good place to start or should I be looking at other possibilities?

 

 

[rcf925]

I always start with the basic compression test or leak down test which is easy to do , That will tell you your basic engine health, Usual culprits valve guides or rings, head gasket as long as your not leaking any.

[jimk]

2 hours ago, cgates30 said:

whitish/grey smoke and seems to get worse as the engine warms up

white smoke is not oil, coolant as pressure in the system builds.

[NYNick]

White/grey smoke is usually coolant. Bluish smoke is oil. You can smell the difference. You can also check the levels to see which is going down.

 

I'd top off both and check them periodically. The coolant should go down faster than the oil level if that's the problem. I'm not sure which one is worse, but burning either is never good.

[cgates30]

I might be wrong about the color. It may have a tinge of blue to it that I considered as grey. I can definitely smell oil burning, but I will check the levels to see.

 

 

[Son of Marty]

The old school way to tell if it's rings or valve guides is with the car warmed up and on a safe road run the engine in 3rd gear up to about 4000-4500 rpms and take your foot off the gas wait 5 seconds and floor it, if you see a large puff of smoke think valve seals, if not think rings.

['76mintgrün'02]

4 hours ago, cgates30 said:

I've adjusted the distributor to minimize the smoke

 

What does this mean?

[cgates30]

50 minutes ago, '76mintgrün'02 said:

 

What does this mean?

 

 

When I first got the car (4-5 years ago) it smoked pretty badly. I replaced the carb with a new weber 32/36 and things got tremendously better. Someone recommended twisting the distributor a little to get the ignition right and that also reduced the smoke I noticed at that time.

[cgates30]

Here's a video, if that helps to clear up the color of the smoke.

[cgates30]

1 hour ago, Son of Marty said:

The old school way to tell if it's rings or valve guides is with the car warmed up and on a safe road run the engine in 3rd gear up to about 4000-4500 rpms and take your foot off the gas wait 5 seconds and floor it, if you see a large puff of smoke think valve seals, if not think rings.

I like that idea. It's an automatic with no tach, but I get the idea.

[Son of Marty]

Yeah I see the blue tint to the smoke, you can do the test with out a tach the rpms aren't that important so long as you get a good vacuum when you shut the throttle.  

[Mike Self]

Some quick 'n dirty rules of thumb for smoke diagnosis:

• Grey(ish) and burnt oil smell--oil (duh!).  Smoking on the overrun--worn valve guides/bad valve stem seals.  Smoking on acceleration--worn rings. 
• White: put a piece of Kleenex or paper towel over the tailpipe.  If it disintegrates or is wet--that's coolant.  If not, it may be brake fluid getting into the intake manifold via a leaky master cylinder and/or power brake booster
• Black:  way too rich mixture (too much gas)

mike