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> Smoke Screen when decel, why??
jsayre914
post Jun 6 2008, 01:50 PM
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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) (IMG:style_emoticons/default/blink.gif)

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.

(IMG:style_emoticons/default/WTF.gif)
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Joe Bob
post Jun 6 2008, 01:52 PM
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Typically that's a sign of valve guides....oil seeping past the insides into the combustion chamber....
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ericread
post Jun 6 2008, 02:00 PM
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(IMG:style_emoticons/default/agree.gif)

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.
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r_towle
post Jun 6 2008, 02:07 PM
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check your decel valve....how...remove it and plug the line for a bit...see if it still happens...

Rich
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jsayre914
post Jun 6 2008, 02:07 PM
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QUOTE(ericread @ Jun 6 2008, 04:00 PM) *

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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.

Are we talking rebuild or what (IMG:style_emoticons/default/confused24.gif)
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Allan
post Jun 6 2008, 02:33 PM
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QUOTE(jsayre914 @ Jun 6 2008, 01:07 PM) *

Are we talking rebuild or what (IMG:style_emoticons/default/confused24.gif)


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.
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SirAndy
post Jun 6 2008, 02:38 PM
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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?
(IMG:style_emoticons/default/confused24.gif) Andy
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Gint
post Jun 6 2008, 02:40 PM
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URY914
post Jun 6 2008, 03:05 PM
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Burning oil is not good for Mother Earth.
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jsayre914
post Jun 6 2008, 03:09 PM
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QUOTE(SirAndy @ Jun 6 2008, 04:38 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?
(IMG:style_emoticons/default/confused24.gif) Andy

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

oil changes the burn rate soooo (IMG:style_emoticons/default/idea.gif)
premium fuel plus oil - /ron + pie sq = 87 octane (IMG:style_emoticons/default/confused24.gif)
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porschecb
post Jun 6 2008, 03:14 PM
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I would think you will have plug fouling issues also. (IMG:style_emoticons/default/sad.gif)
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TeenerTim
post Jun 6 2008, 03:21 PM
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QUOTE(porschecb @ Jun 6 2008, 05:14 PM) *

I would think you will have plug fouling issues also. (IMG:style_emoticons/default/sad.gif)

(IMG:style_emoticons/default/agree.gif) The plugs will foul and build up deposits. I've seen them where the gap is completely closed by oil and carbon build-up.
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ericread
post Jun 6 2008, 03:25 PM
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The CHP will pull you over and ticket you for violating SMOG laws.
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jsayre914
post Jun 6 2008, 03:29 PM
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QUOTE(ericread @ Jun 6 2008, 05:25 PM) *

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

CHP cant catch me in Maryland (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/driving.gif)
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jsayre914
post Jun 6 2008, 03:55 PM
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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.???
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brp986s
post Jun 6 2008, 04:15 PM
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QUOTE(SirAndy @ Jun 6 2008, 01:38 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?
(IMG:style_emoticons/default/confused24.gif) Andy


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.
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Katmanken
post Jun 7 2008, 11:51 AM
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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......

Kensengineautopsyservice
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