smoke on decceleration only

Fellas trying to get to the bottom a issue with my 200. I'm not sure if it is a timing issue. I pulled all the plugs when I got home afte a hour drive and all the plugs were clean and looked great. I have the ignition set at 14deg but I know that I could add more timing because I haven't advanced yet to get any pinging. Should I just keep adding timing or is it a valve timing issue? ANy ideas would be great.
Kev

Howdy Kev:

If it is smoking on deceleration you likely have major problem. If it is smoking after deceleration and then stepping on the throttle, you likely have a valve guide seal problem. The engine is sucking oil down the valve guides during high vacuum on deceleration. When you step on the gas you see it in the rear view mirror.
If that's the case it's time for some new valve guide seals.

Adios, David

White smoke or black smoke?

I bet you have valve guide wear on #5 or #6.. when you let off the gas its drawing the oil through the guide.... Mine has the same issue after I knurrled these guides.

Frank

Well I had the head done with new guides, seals, and seats recnetly. There no smoke at Idle even when hit the gas then off. My dad followed me down to woodburn yeterday and said that at cruising there no smell or sign of gas only when I shifted he said. I had noticed some when I engine break slightly before downshifting. I only have abuout 200 miles on the head since rebuild and the there was no oil fouling on the plugs?

My vote is valve seals. When you engine brake the vacuum in the intake side is at its max and will suck oil past worn(freshly knurled) guides and valve seals. Some valve seals work better than others. Anyway that oil goes through the cumbustion chamber without burning because there is no fuel to ingite it. It collects in the exhaust and when you get back on the gas it is burned making white or blue smoke and never fouling a plug. If you just recently had the head done I would start at the machine shop that did the work. If you assembled the haed yourself what style valve seals did you use. You may be able to pull the valve cover and spot a misinstalled seal. If you have more questions on were and what to look at post back. Rich

Might want to check crankcase ventilation as well, does the PCV valve seem to be functioning? They're cheap to swap out.

welll pulled the cover off this afternoon. everything looked good maybe one of the umbrella seals got hung up. I have'nt had to add any oil, levels were good. stumped..

You say your using umbrella seals. Are they the large diameter seals that ride on the valve stem. If they are thats your problem. Basicly umbrella seals suck. The seals to use are the ones that press onto the end of the valve guide and have a little spring around the valve stem part of the seal.

If you have an auto trans, check the vacuum modulator to see if the diaphragm is ruptured. This will suck tranny fluid out of the trans & will smoke on coasting.

Do a compression check, then a leak-down test by adding a little oil to each cylinder and see if compression raises. If not, valve seals, if it does raise, rings. My 90 mustang is smokin like that and unfortunately its the #5 ring
Matt