This is a continuation for a different post, but since it's a new problem I'm starting a new thread. (Pre post... I was a dumba$$...)

She's a 89 F250 7.5L manual with o/d....

She smokes consistantly inconsistant. That is... I had a problem starting her (see pre post) and since found that issue but in the mean time, unclogged the AIR injection system diverter valve muffler (previous owner had it duck taped shut)...changed the PCV valve and grommet, found the number 5 and 7 wires to the wrong point on the distrumitor... am in the process of changing the O2 sensor....

...she runs smooth as silk, but smoke worse that Geroge Burns...inconsistantly... when I took her for a test run last night, she smoked for the first 5 mins or so... then would only smoke when I disengaged the clutch to shift... then took her on the freeway for about 5 mins and she cleaned up, a little puff of smoke when I "laid into her" to make a yellow light... so I decided to take are on a 15 mile trip up a hill to the next town, and when I got there she was smoking again.. then when I got home, just as worse as she was when I started... I smells like unburn fuel... you tell when it hits the eyes...

anyone else has such an experience or insite? thanks...

 

Smoking on deceleration is a valve seal.

 

I'd pull your plugs and check to see if you have any oil fouling. Sounds like a tired motor to me.

 

Thanks for the insights... I pulled #1 and #2 plugs and both looked pretty bad. Covered in soot. Would this be causing the smoke?

 

Black smoke is fuel smoke.

Blue smoke is oil smoke.
Intake valve guides and valve seals will smoke on startup and deceleration.

 

Thanks for the info... what are the dangers of not replacing the valve seals? I need to take a long trip...am I f'ed?

PS... what if I used slick 50? would that help... thx

 

Nothing is going to magically fix the valve guides.
They must be worn. If so, your truck needs a valve job. (sometime)

I would probably change my spark plugs for uncontaminated ones and keep an eye on my oil level.

A little oil smoke would not keep me from using my truck.

 

Spark plugs should look baby poop brown not black or white

 

Really?

I haven't noticed this since the days of leaded fuel.
The again there was the MTBE era when they always looked rusty or orange.
Now, mine mostly look like new. Perhaps some heat discoloration of the ground electrode...

I do make an effort to change them every year.

 

..and if they are black and look like there is oil on the threads???

...the person that worked on the truck before me had two of the spark plug wires miss wired, so she was running bad. This may have fouled them. Also, I just check the radiator and there is a slight milky film in the coolant, probably not good either...?

 

Milky junk rad means head gasket, is it like a coffee colored shake...thats very bad if it is.

 

Head gasket? No coolant in the oil right ? IDK if the oil cooler can fail and make this happen in our fords. Oil fouled plugs can happen many ways. Seals like talked about above can do it and the worst case cylinder scores and bad rings. An compression check will rule this out. A small puff of blue smoke on start up or on deceleration I would not worry about. But when you put the pedal down and it lets out its smoke ... Not good.

As far as the dead plug wires the plugs should be gas fouled (wet and stink like gas) not oil fouled (look's like liquid tar on and in the isolator).

 

thanks for the good info guys,

the coolant/antifreeze is fairly clean, just a slight milk flim. Could the film be bad heater core? ...

I'm changing the plugs now, and oil. I'll let you all know what happens when I'm done... thx again...

 

Thanks for the insight! Here's what I did and how it went...

I changed the O2 sensor, oil, and plugs... she is not smoking (as much, only at first start up...) so I'm going to take her on the trip, well move 550 miles away...) I got some additive to add to the gas to clean the injectors etc....

Long story short... I think she will be good to go... thanks again...


-aa