I have read tons of threads and couldn't find a direct answer. So I got this 96 civic 2 weeks ago for pretty cheap. It was not smoking at all when i first got it. I brought it home and did some maintenance on it. This is the list:
Seafoam
Spark plugs (platinums)
Fuel filter
The car had no smoke after all of this and ran great.
The next weekend I replaced the timing belt, water pump, tensioner, belts, oil an filter. When i drained the radiator fluid, i noticed a small amount of oil in the coolant but didnt think anything of it. I used 5w30 oil.
When I start it up now it smokes. Not really blue just white. When reved up it blows even more. I let it idle for 10 mins yesterday and still blew white smoke when reved and a small amount if white smoke at idle. The oil isn't milky. The smoke smells like oil. Is it time for a head gasket? Or is this blow by on the rings? I bought the car to tune it up, do the timing belt and water pump, and resale it to make a little money so I don't want to tear the engine completely apart but I don't want to screw over the buyer. Thanks guys

 

do a compression check.

 

If you found oil in your coolant, it is almost certainly a head gasket failure, sorry to break that news.
But I'd do as racerx510 suggests, beg, steal, or borrow a cylinder compression gauge.

That will at least tell you which cylinder has the 'blow'. Many times it's at one of the four corners or
between the two middle cylinders.

 

Dont steal a compression gauge. Yes sounds like a headgasket with oil in coolant.

 

No sense of humor... it's an old expression that equates to 'you really need one of these'.

 

lolll at you thinking I was seriously concerned about him stealing a gauge. This is Merica! we steal cars and drugs.

 

the coolant hasnt went down any and my oil looks as fresh as it did when I changed it sunday. The coolant has something in it but im not 100% sure that its oil at this point maybe just dirt. It tends to float on top of the coolant and I would think if it were oil it would sink considering that oil is heavier than the coolant. compression test was good in all 4 cylinders. I have a buddy that owns a shop and got him to check it real quick on my way home today. im stumped.....

 

How old is your cat? might be a dumb question but how warm is it where you live?

 

I might just be deposition of clumped rust and minerals due to infrequent coolant changes.
I would do a cooling system flush with a flush chemical, or if you don't feel comfortable
doing it yourself, a dealer or outside mechanic can do it for you.

It often can look like emulsified oil in the coolant. Also, rinse out your coolant reserve
tank. If there are deposits that don't come out, you definitely need the cooling system
flushed and recheck.