engine break in issue

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72plymouthscamp

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Hey guys I have a problem fresh 318 .040 over kb167 cast rings 302 heads milled .025 smokes like crazy even after abouth hundered miles on it but it only smokes while it is idiling or if stoped at a light. Could this be a valve seal problem? Now I will mention the have been machined for the teflon seals but the place I had bought my parts from said they were out of stock and to use the umbrella seals instead. Let me know what you guys think. Thanks in advance.
 
Out of tolerance valve guide clearance and/or incorrect seals will make it smoke at idle and de-acceleration. I'll be straight with you and say it should never have been run with the umbrella seals.
 
Yep! It most likely didn't do any damage beyond carboning up the chambers and backside of the intake valve. The teflons should be easily obtained online if necessary. :)
 
If it smokes while your driving the car then it can be more than just the valve stem seals. IMO. Valve stem seal smoke will generally clear up some when driving, unless the guides are that loose then the shop should have never let the heads go out like that.
 
BJR Racing said:
If it smokes while your driving the car then it can be more than just the valve stem seals. IMO. Valve stem seal smoke will generally clear up some when driving, unless the guides are that loose then the shop should have never let the heads go out like that.
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i agre my self i dont like thos teflon seals.they take HP away. idont use seal at all in my motor and it doset smoke at all.that sounds like an intake gasket leaking.to me i know it has hapend to me in the past.thats my thought
 
Intake could be leaking.... I found out that mine was leaking when I removed the intake. The car would smoke mostly while idling and at stop lights.
 
Another vote for checking the intake gasket. Had it happen to me years ago on a fresh 340.
 
I'll vote for an intake leak, as well.
I will add that milling the heads may have had some affect on intake seal, especially if the intake is a used aftermarket piece of unknown history.

I ALWAYS use the Blue Fel-Pro intake gaskets on the 340/360 smallblocks, (not sure if there is a 273/318 version) but they are a bit more forgiving of imperfections and, in a pinch, I have actually re-used them on intake swaps with no ill affects.

Mark.
 
Also check the PVC valve and hose that leads to the carb for oil contamination... just a small amount of oil being sucked into the intake will make a motor smoke also.
 
well I pulled a few plugs out they look great no oil on them also was able to look at the piston tops no signs of being wet with oil. It does no smoke at all while driving only while idiling or stoped at a light. I did notice that the intake gasket shows signs of being wet with oil around the runners, they are fel pro gaskests.
 
Holley 670 street avenger I have it jetted all the way down as low as I can go also i have oil comming out of my mufflers!!! So I dont think its gas smoke but thank you for the suggestion. The car runs great outside of the smoking thing, im thinking ( hopeing ) its stem seals. I will start there and see where it gets me. So thanks to all for the input its been a great help.
 
unbolt the headers and look in the exhaust runners for oil. if its in there then you probably have some seriously worn guides.
 
What do you mean by "oil out [your] tailpipes"? I would suggest a leak down test to check the overall condition of the engine. Poor sealing valves or rings will show up that way. Moly rings take a very smooth finish to seat correctly and they should be seated once the cam's broken in.
 
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