Smoking 273, opinions?

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TX64DartGT

TX64DartGT

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My 273 is smoking fairly good out of the left bank when I'm on it over half throttle or more and above 3k RPM. Compression tested all cylinders and all were 105-110, but the plugs on 6 and 8 are oily. I replaced intake valve stem seals with new felpro seals on 6 and 8 and plugs are still oily after a new set and it still smokes. I was lazy and only changed the intakes on 6 and 8 instead of every seal on every valve, mostly because I've been limited on time to wrench on it.

I have NOT done a leakdown on it yet. Starting to think the rings have gone to **** on 6 and 8 and that is my problem. Any thoughts?

Engine is stock bottom end, hydraulic flat tappet comp cam 279/296 .486/.473, stock 318 heads, Eddy performer intake and 600cfm carb.

Gracias Gents!!!
 
How long has it been since the head swap and the intake? Did it smoke before that?
 
if the valve guides are worn,the new seals can only do so much. I dealt with that this year -I had the similar problem with my right bank. i half fixed it to patch it up,got tired of the "Dude! You're really smoking!" comments ,had a set of X heads built.bought a short block318 and now just wait til Springtime comes to this damned Yankee town when I can beat the piss out of this thing. "Test" drives have already made me see tire smoke instead of engine........................
 
Check all the intake bolts, it might be sucking oil vapers from under the intake on 6 & 8 runner
 
JBurch said:
How long has it been since the head swap and the intake? Did it smoke before that?
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I've had it for a year and its done it since I've owned it. The guy I bought it from neglected a lot of the maintenance because he would let it sit for a loooong time and almost every gasket dried up and developed a leak. The build probably only has around 2000k miles on it and is around 8 years old.

brian6pac said:
Check all the intake bolts, it might be sucking oil vapers from under the intake on 6 & 8 runner
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This was my next thought, I wouldn't be surprised if the gasket was shot, every other external gasket had been.
 
TX64DartGT said:
I've had it for a year and its done it since I've owned it. The guy I bought it from neglected a lot of the maintenance because he would let it sit for a loooong time and almost every gasket dried up and developed a leak. The build probably only has around 2000k miles on it and is around 8 years old.

This was my next thought, I wouldn't be surprised if the gasket was shot, every other external gasket had been.
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Smoking when you are hard in the throttle and the intake vacuum is low is not normally caused by intake leaks. The general symptoms of smoking out the pipes at high RPM's and hard throttle indicate ring problems. OP, I assume this occurs with sustained hard throttle (not just smoking when you first put the hammer down and then it clears up)? Who knows if the hone was right, the bore was right, if the ring gaps were right, if the ring side clearances were right, etc....
 
nm9stheham said:
Smoking when you are hard in the throttle and the intake vacuum is low is not normally caused by intake leaks. The general symptoms of smoking out the pipes at high RPM's and hard throttle indicate ring problems. OP, I assume this occurs with sustained hard throttle (not just smoking when you first put the hammer down and then it clears up)? Who knows if the hone was right, the bore was right, if the ring gaps were right, if the ring side clearances were right, etc....
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Yessir that's the problem. Smoke blows until I lift the throttle and then it goes away, I fear its the rings in those 2 holes, but with as much problems as I've had with gaskets on this thing I was holding out hope for cheap and simple and not a tear down.
 
UPDATE.

So today I finally got around to checking inside with a scope. Walls still looked good and could still see cross hatch. To my surprise the pistons have valve reliefs which I did not know, so I bump the starter a few times to get looks at the entire bore when suddenly a big fat oil drip comes running down the cylinder wall! Check out the photos.

So before I pull this head off I’m thinking cracked head or valve guide.

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I would pull the intake first and look for oil in the runners / I have loosen all the intake bolts and re torque some and they stopped leaking and idle better.
 
TX64DartGT said:
Yup. My best guess is the valve guide is wallered out pretty big.
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But if you had the rocker covers off to change the intake valve stem seals and you obviously had a "head on" spring compressor to remove the retainers and locks from those intakes, why wouldn't you have checked the valve stem movement on those sus valves when you had the chance? Doesn't really make sense to me at this time why you didn't wiggle those valves in the guides to see how much play there was. That would have either confirmed or eliminated worn guides. And if you were not sure on how much play was acceptable, easy enough to remove a couple more springs from some good bores and compare the valve stem movement on them.
 
70Hardtop said:
But if you had the rocker covers off to change the intake valve stem seals and you obviously had a "head on" spring compressor to remove the retainers and locks from those intakes, why wouldn't you have checked the valve stem movement on those sus valves when you had the chance? Doesn't really make sense to me at this time why you didn't wiggle those valves in the guides to see how much play there was. That would have either confirmed or eliminated worn guides. And if you were not sure on how much play was acceptable, easy enough to remove a couple more springs from some good bores and compare the valve stem movement on them.
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I did and it wasn’t that bad.
 
Pulled intake, #6 and #8 were my problem with oil leaks, think this may have been the problem. No gasket material on the intake when I pulled it, every port had something wrong.

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Looks like wrong gaskets. 273/318 ports are much smaller than 340/360 ports.
 
Looks like PO ripped the crap out of the gasket taking the intake off and just pushed it back into position and retorqued it to start and sell. Nice guy.....Intake gaskets are cheap, good catch. I got a borescope for Christmas, have not used it in the car yet; did find a rodent hiding under the dishwasher though!
 
you didn't have enough clamping force on the gaskets ,your intake bolts might be too long of a shoulder on them or the china wall and intake are bottoming out not letting the intake seal on the runners did you use the thick cork gaskets or rtv . also did you remove the pins aliening the end gaskets. hope you don't need to do it twice.
 
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