White smoke at idle, out of ideas!!!!

[TucsonHooligan]

Ok, so it's still smoking, but about 75 percent less now. I pulled the main jet and its a 55. Too big or what? Two jets up top are 180 for the primary, 195 for the secondary. So what direction should I head?

 

[chad]

random thought:
what's goin on w/the choke?
(not sure that would have caused the huge smoke prob B 4,
but I didn't C it to compare)
U "don't like" the ring or valve seal diagnosis? Seems logical 2 me.

 

[69.5Mav]

it's still smoking, but about 75 percent less now

Good. My best bet at this point is that the rings were put in upside down. This will lead to smoking though your symtoms are wierd BUT they will wear in.
Best guess is that the rings are not scrapping the oil back into the pan as well as they would with them upside down and a rich mixture was washing that remaining oil down and burning it.

It will just take longer for them to wear in. If the rings were broken or the gaps lined up this would never improve.

How many miles do you have on it now?

How many miles do you get to the quart of oil?

 

[TucsonHooligan]

Its not really a matter of not liking the diagnosis, I mean, of course it sucks, but its a matter of trying every last little thing before goin in and tackling such a major project. Easier to turn a screw and replace a jet before tearing down a motor, no?

I have maybe a few thousand miles on it now, though I haven't really measure it in realtion to oil loss. If its running rich due to an oversized idle jet, how much smaller should I look to go? I have the mixture screw like half a turn out and it still runs, tho choppy, and that seems to be what reduced the smoking. No more flooding the intersection with a giant cloud. Or is my 55 idle jet sufficient and I just have to wait for the rings to break in further?

 

[69.5Mav]

Try giving it a little more juice.

The Plugs could tell us a lot about how it's running. What do they look like?

Also the exhaust pipe is worth giving a look see.

What carb do you have?

In Tucson you are up at about 4000 feet or so. This will mean that you will need a smaller jet then at sea level. Don't know if yours is right or not.

 

[TucsonHooligan]

Carb is a HW 5200. And what do you mean by give it a little more juice? Richen it up with the air/fuel screw? I'll pull the plugs this saturday and give em a look.

 

[69.5Mav]

give it a little more juice

Yes, richen it just a tad, maybe 1/4 turn.

There is a post among the stickies about jetting 5200s.

viewtopic.php?t=23153

Examin the tail pipe as well. look at it for color and consistancy and feel the contents between your fingers. A car that's burring oil will have an oily build up in the tail pipe.

 

[woodbutcher]

Hi TH.Was just reading an article in MM&F last night,and was wondering weather your valve SEALS were TEFLON or VITON?An engine was built and it smoked.Went through twice more,before it was found to have TEFLON valve seals.Changed to VITON.Smoking QUIT.
Might be worth double ckecking the valve seals for material type.
Good luck.Have fun.Be safe.
Leo

 

[TucsonHooligan]

Thanks, I'll richen it up tomorrow when I'm off and check out that sticky for some tips...


I'm not sure on the type of valve seals, they were whatever the shop that rebuilt it put in. Anyway to tell by sight andt touch what they are made of?

 

[woodbutcher]

Hi TH.Don`t know the answer to that one.I am sure that there is a more knowledgeable person here than me who can answer that question.
Good luck.Have fun.Be safe.
Leo

 

[69.5Mav]

How is it running now?

It might be time to retest compression and leakdown to see if any improvement is occuring.

 

[69.5Mav]

Any updates?

 

[MustangSix]

It's been awhile since you started this adventure. Just one more easy thought....

Did you ever check the PCV valve? I once had one that was sucking oil from an unbaffled valve cover causing a big cloud of smoke, but only at idle. At higher rpm the vacuum tailed off and the oil sucking wasn't noticeable.

 

[wsa111]

Jack, i believe he has already blocked off the pcv system from a previous post.

I pulled the valve cover and the seals look good. The block was zero decked and the head shaved for compression. Gonna try the drizzling oil technique, see if that yields any results. PCV system isn't the issue, as I pulled it and plugged the vacuum with no change in smoke.

All the short block machining was done by a reputable machine shop that has been used by numerous friends with top notch results and is owned by a builder/racer, so I'm thinking the weak spot in the build is yours truly. I'm still gonna exhaust all other options before I get drastic tho...

EDIT: Tried the drizzle down test, no visible change in smoke. There is an awful lot comin from the rocker assembly area though, kind of filled the engine bay a little. That a clue to anything?

Darn good idea, but he states that the pcv is not the issue.
What kind of valve cover are you using?
If its a stock ford the baffles are there.
If its a cast aftermarket valve cover you should always use a baffled pcv grommet.

 

[MustangSix]

Missed that, Bill.
How about the transmission? If this is a C4, a bad modulator can feed oil into the intake system and cause a lot of white smoke as well, particularly at idle.

 

[69.5Mav]

Any Progress?

 

[69.5Mav]

Any News?

 

[78merKri6]

T.H. I'm sorry,but I believe your leakdown test may not reveal oil consumption culprit. Also you shouldn't have more than 10% leakdown on fresh engine. Leakdown can't tell about oil rings! I once tried teflon valve seals---didn't work. Even fresh early umbrella style seals would dry an engine up if rings and guides were good. You may have to correct piston ring discrepancy,replace valve seals with new PC style and look at/study your PCV system. M y experience has been that bad guides/seals cause the symptom which you describe. "Bad" or worn rings usually cause heavy or dark smoke under hard acceleration. By now you should have enough info to find and fix your problem. These people are helping you. Anyway,press on. I wish you the very best. Couldn't stand it any longer----just had to chime in. Gary.

 

[69.5Mav]

Any new developements

 

[78merKri6]

CH, I'm interested to know of deveopments; if you've found cause of smoking. G'luck. Gary.