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OMG stop smoking already!!!!

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Hooper11772

Hooper11772

Senior Member
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Hi All,
I've been struggling for the last few weeks trying to get my car to stopsmoking. I removed the engine early this past winter and have since re-installed with a fresh oil pump and a new pan gasket. After install I added the new oil(4 quarts) and upon start up the the car was smoking. In addition to the smoke I also had a leak due to the positive crank case pressure present that I mentioned in an earlier post.

Well I got the car to stop leaking by adding an oil catch can sytem vented from my timing cover to catch can then to intake manifold. I used clear tube so I know that no oil is passing the catch entering my intake so I have no idea where the oil producing this smoke is coming from.

I pulled the spark plugs and did a compression test on all cylanders and the average was between 60 to 90 PSI. The Pistons and rings are only a year old and have had very little use so I dont think its blow by. Also the pressure holds if I leave the guage on there.

The plugs are black from burnt oil. Looking through the plug ports I can see oil residue in the chambers all four of them equally. The only thing I can think is I overfilled with oil and it somehow worked its way into the cylanders?? But 4 quarts seems like the right amount so did I fill it to fast would this cause it to happen?

It's so bad i'm spitting oil out my tailpipe. Any help would be GREATLY appreciated i'm kind of at a loss.
 
Are you sure it is oil and that it is not the carbs running rich?
 
What kind of PCV valve are you running? Mine smoked a lot until I fitted the right PCV valve. I tried aftermarket units and an oil catch can to capture the oil vapors from being sucked into the intake. Finally fitted the original pancake style and the smoking stopped.
 
60 90 psi seems a bit low. Can you do a leak down test? it is possible you rings may not have seated. what condition is your head in? are the valve guides worn?


m
 
How do you test for worn valve guides?
 
I have an inline PCV unit from advanced auto. Nothing special but i'm positive that the oil is not coming through the intake. I've actually disconnected the whole system and the car never stops smoking. I also have clear lines and can see that no oil vapor is entering the intake from the timing cover.

I wasn't sure on the compression number either however I can tell you when I first rebuilt this with the help of another member on the forum the compression was the same and there was no smoke. Also all 4 have oil in them ie plugs wet with oil definitely not gas. I figured even if I had blow by in one cylander all four seems unlikely.

I went through the head as well the valves and guides were in good shape.not new but very little to no play and I lapped the valves/seats.

I read on a previous post tha someone overfilled their oil capacity and this exact issue occured. When i was filling the oil for the first time it did back up a bit but eventually went down. I'm not sure if this would cause the issue but i'm thinking I may drain the whole engine and refill.

Does this sound possible?
 
Check engine with the dip stick. Extra oil will cause the prob for sure.

How many miles on this?
 
You mention that the pistons and rings are recent. When this was done, were the valves,seats and guides also done? When the bottom end of and old motor is strengthened, it over-loads the top end where most of the sealing is done to obtain vacuum and compression. 60 to 90 is almost too low to run a motor, so either the rings never seated or the valve guides are worn out. I am not sure if these motors have stem seals, but they harden and crack off if they are old and oil will get sucked into the intake.
Bill
 
The pistons and rings are new and were installed last year. I probably ran the car a total of 5 hours with the current setup. I asn't sure on the compression I looked in the haynes manual and couldn't find the recommended PSI for each cylander. I also had some questions regardng the compression test itself on how to perform it specifically.

For instance I threaded he compression tester into the spark plug hole and then
turned the car over for approximately 10 seconds.Once complete I checked the PSI on the guage and it was around 60 -90 as previously mentioned. It held this PSI for as long as I left the gauge on. I figured this was good since that means no pressure is leaaking out of the cylander??? I'm not sure if that reasoning is correct but thats what I was thinking.

Does anyone know the recommended compression for these cars? The valve guides were not replaced but seemed to be in good shape. As for the stem seals they are all new i'm pretty sure those are the rubber things right?
 
Hi Roger:
Sorry to see you are having engine issues. How many miles have you put on the engine since the rebuild? Echoing some other responses here it sounds like the rings haven't fully seated - you didn't use synthetic oil during breakin, right?
As for the valve guides, there basically should be no play at all as it doesn't take much extra clearance for oil to be pulled into the cylinders.
Again, given the low compression across the board it just sounds like the rings didn't seat.
And you are taking all the spark plugs out during the compression test? Gotta let the engine spin as freely as possible.
Roy
 
Oh and Jack I checked the dip stick and it read a little less than full so i'm not sure if it's inaccurate or not. I did switch to a purolator spin on oil filter and my pan has a couple of dents nothing huge but a few. Is it possible the car holds less than four with these considerations?

Thanks for all the help guys. Chris S helped me rebuild this motor and he really knows his stuff. Unfortunately he's been out of town for a while and i've been left to my own devices. This forum definitely helps though.
 
When you compression tested, did you have the carb pistons propped open and the butterflys open?? That's the way I've always done it to ensure you're drawing a full charge of air from the intake. If not that probably accounts for your low readings.

As for oil, I found it interesting that you said when you filled it that it took awhile for the level to go down. I assume you mean what you could see through the oil filler. That could indicate that the drain holes in the head that allow oil from the rockers have some blockage. Take the oil filler cap off as it's running and see if the rocker cover is filling. If it is, then it's probably running down the valve stems.
 
So Roy I should remove all plugs when doing the compression test? I only removed the one I was testing and then moved to the next. That may be why compression is so low?
 
Thats what i was thinking Mike P. It seemed odd that as I filled it with oil for the first time it took a long time for the level to go down. At one point it actually backed up to the brim of the oil fill hole. I thought at that point if the oil filled the rocker cover than oil could have leaked into the cylinders and is still in there.

I also did not lift the intake pistons on the carbs so there would have been some blockage there as well.

So i'm clear I should remove all plugs,lift the pitons on the carbs and then check each cylinder individually to get compression?
 
I need to do this again soon too. I've been told to use jumper cables so the the battery doesn't start to loose umph by the last cylinder, therefore giving weaker numbers for that last cylinder, probably anal. Should the engine be warm at all?
 
All the back up of the oil durring filling means is that you filled it too fast. Thick oil small holes = slow.
 
Jack, thats what I figured but I guess i'm still wondering if filling it too fast caused it to seap into the cylinders some how?
 
<span style="font-weight: bold">For instance I threaded he compression tester into the spark plug hole and then
turned the car over for approximately 10 seconds.Once complete I checked the PSI on the guage and it was around 60 -90 as previously mentioned. It held this PSI for as long as I left the gauge on. I figured this was good since that means no pressure is leaaking out of the cylander??? I'm not sure if that reasoning is correct but thats what I was thinking.</span>

Most compression testers have a check valve (like the ones on tire valve stems in the end of the hose) this holds the highest pressure seen during the engine cranking if yours does have this it will hold the pressure until you press the stem in releasing the pressure. It is not an indication of cylinder leak down.
 
Hi Roger:
Yep, have all the plugs out when you make your compression check and also prop open the carb slides as Mike suggested.
I suppose anything is possible but I doubt oil got directly into the cylinders as a result of adding it too quickly.
You just need to eliminate issues as you go, that is make certain your oil level is correct and complete the compression test as suggested. Also, maybe take a break and relax before proceding!
Roy
 
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