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Posted by: jsayre914 Jun 6 2008, 01:50 PM

so I replaced all vacume lione boots elbows seals fuel injectors fuel lines Everything is super tight. Mps is fine. Drives Great, really quite a bit of pickup.

car is a 73 2.0 w/ FI (obviously)

SO when I accelerate onto freeway Everything is great but when I remove my foot from the throttle I get clouds of white smoke, kinda like James bond. I press on the gas again and it is gone, at a steady speed it is gone only when i slow down does it smoke.

Posted by: (*)(*) Jun 6 2008, 01:52 PM

Typically that's a sign of valve guides....oil seeping past the insides into the combustion chamber....

Posted by: ericread Jun 6 2008, 02:00 PM

White smoke on decel, or on engine braking? Hard engine braking can pull some oil through the valve guides, not too much of a problem, just don't use the engine to decellerate that hard.

White smoke on a normal decel - not good.

Posted by: r_towle Jun 6 2008, 02:07 PM

check your decel valve....how...remove it and plug the line for a bit...see if it still happens...

Rich

Posted by: jsayre914 Jun 6 2008, 02:07 PM

Are we talking rebuild or what

Posted by: Headrage Jun 6 2008, 02:33 PM

Yer talking at least a head job if it is valve guides but, once you start, DWD will set in and it will become a complete resto.

Posted by: SirAndy Jun 6 2008, 02:38 PM

stupid question of the month:

what does oil seeping by the valve guides actually hurt inside the motor ???


i mean, other than a cloud of smoke and a bit higher oil consumption, what bad comes from oil seeping by the valve guides ???

any good reason why you couldn't just drive the motor as is?
Andy

Posted by: Gint Jun 6 2008, 02:40 PM

That's what I do...

Posted by: URY914 Jun 6 2008, 03:05 PM

Burning oil is not good for Mother Earth.

Posted by: jsayre914 Jun 6 2008, 03:09 PM

Is this where I tie into the Gasoline thread......

oil changes the burn rate soooo
premium fuel plus oil - /ron + pie sq = 87 octane

Posted by: porschecb Jun 6 2008, 03:14 PM

I would think you will have plug fouling issues also.

Posted by: TeenerTim Jun 6 2008, 03:21 PM

The plugs will foul and build up deposits. I've seen them where the gap is completely closed by oil and carbon build-up.

Posted by: ericread Jun 6 2008, 03:25 PM

The CHP will pull you over and ticket you for violating SMOG laws.

Posted by: jsayre914 Jun 6 2008, 03:29 PM

CHP cant catch me in Maryland

Posted by: jsayre914 Jun 6 2008, 03:55 PM

Hey Guys & Gals

I just did a search on "smoke" and found out if you overfill with oil you will get a tone of smoke out of the pipe. I did just fill her up befor she sat... I know that i overfilled it buy at least a 1/2 quart.
...it was dark
I didnt even think anything of it til now.

Could this be the answer for me.???

Posted by: brp986s Jun 6 2008, 04:15 PM

If the guides are worn they are less able to transfer heat from the valve which can fatigue the valve potentially leading to disaster.

But, 914-4 don't have valve seals and my experience is even with healthy motors they will smoke on overrun, more so if it is hot out. But my decel valve is MIA.

Posted by: kwales Jun 7 2008, 11:51 AM

If it's a bad enough of a leak past the guides, the oil in the combustion chamber area can burn and form a really nasty layer of "coke" or burned oil residue that is attached to the cylinder head and some on the top of the piston.

Can you say reduced chamber volume and higher compression?????

The higher compression can result in hotter running heaads which leads to burned or separated exhaust valves and in some cases the amazing floating detachable valve seat......

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