I'll be curious to the result tomorrow. I was kind of wondering when you started this if it was just dry seals from sitting four years. Might get better after a day or two.

Unless a magical mechanic helper mouse did the valve seals last night while I was sleeping.

Don't get me started on mice. I was smelling mouse piss in my car recently. No sign of the little shit, though.

This weekend while doing my shock install I pulled the panels in the trunk to get at the shock tower bolts. Apparently, auto insulation makes a nice mouse house. There was one square of insulation glued to the deck next to the shock tower on the passenger side. Well, there used to be. It was in a heap with a nice little doorway in it. Pitched it and all seems well now. Bastard.

I guess I purged the cylinders yesterday. Today (24 hours later) there's no smoke at startup. I took off for a drive cold and still no smoke. I am happy. :D

Nice work! Glad that it was just in need of some miles!

Congrats on not having a larger problem.

Cheers,
Matt

I need to follow up on this. I'm not sure how the hell the car didn't smoke 24 hours later as reported above, because that never happened (or didn't happen) again. Ever since it has smoked like holy hell on a cold start.

I had a set of valve seals sitting around so I installed those using one of the miracle valve tools (which worked great btw - once I figured out a good technique.) That work yielded no change at all even though the old seals were hard as rock and coming apart.

After going through list of everything that could leak oil into the cylinder from up above and not finding a single fault, I had to face the fact that the oil ring(s) could be the only source. I soaked them in seafoam in hopes of freeing stuck rings. No change.

In the end Jay was right, oil rings. And here's why (at least I think). On cold start the compression rings are passing oil up to the combustion chamber from the worn oil rings. So the engine has to rotate a bit before getting enough oil up in the cylinder to combust - thus the 12 or so second delay for smoke out the tail pipe. As the compression rings (among other things) warm up, they expand and do a reasonable job of managing the oil in typical driving.

Garage work is about to start so I really don't have a spot to pull the engine and do a re-ring/hone OR pull and install the FE which sucks. Talk about mixed feelings. :giggle:

Sorry it wasn't something easier :( Yay for being right though!

I have the same issue with a '90 I bought last year for my mother-in-law. I bought it thinking blown head gasket and had the head reworked w/ new valve seals and replaced the head gasket. I still smokes on startup but later clears up. It also passed emissions fine. I have also come to the conclusion that it is bad oil rings and may pull the engine this winter and re-ring it.

Although I've done some more reading - especially on vintage sites, and these guys swear that using seafoam or ATF or marvel mystery oil WILL free up oil rings. Requires soaking for at least 24 hours (mine sat less) and even multiple applications. Basically they're saying that you're not going to have bad oil rings without bad compression rings- and I've got good compression. Maybe I'll let it sit longer for another try with seafoam. Don't have much too lose anyway. ;)

I've done Seafoam and Marvel Mystery Oil with no luck. I also used Rotella high detergent oil for 1 oil change.

What's the compression numbers for the engine? hot? cold?

Did you do a long soak, no spark crank, another long soak and no spark crank... and then a drive? I've literally read several posts that support a lot more effort in this than I've done. And again- nothing to lose here.

The last time I did the compression test, the numbers were up since those above... I'm not exactly sure why. But they are now nearly the same hot and cold (probably some oil in there on the cold) - both around the 190s and only 4 psi difference from highest to lowest. My original 1.6 was making high 140s and still running fine supercharged - no oil adding between changes.

it's working
 

So far I've done three full engine cylinder soakings on this engine. I did a single seafoam soak on what I thought was the problem cylinder overnight = fail. No visible change. Then got serious and did a full engine seafoam soak overnight, but it didn't appear to do much. So I went with a two day soak on all four using Marvel which has some oil in it. That showed a noticeable improvement on cold start yet there was still substantial oil fogging. High rpm warm thrashing was dramatically improved. The final and third soak was seafoam on all four cylinders that I let sit for a three days and now I'm only getting a small bit of smoke at the magical 13 seconds after startup with a short duration and none after warm successive high rpm beatings. This is a huge improvement over the mosquito fogger it was in the beginning - it would literally hide the car in it's morning startup oil fog. Might do another marvel oil soak since I have some left and the seafoam is all gone. But I figure this is worthy to note given the cost vs. the other option. :D