Dead Cylinder..flat cam lobe?

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T56MaxTorq

T56MaxTorq

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Took the duster out for a ride and some carb, kickdown linkage adjustments and noticed a LOT of smoke out of the passenger exhaust. I have headers and duals. Ran a compression check and #2 is 0-30 psi. Bubbles in the radiator. Pulled the valve cover and the intake roller rocker adjuster was gone..laying in the top of the head. Unsure if the cam is now flat. I put it all back together and wanted to check gross lift of the valve but my dial indicator only sweeps .20" Any other way to check to see if it's bad without taking off the intake? Maybe a mechanics ruler would at least see if I have .5" lift. Too dark and frustrated to work on it tonight. Any help would be appreciated.
 
Well nevermind..I tried to measure anyways and my dial indictor is perfect cause the valve doesn't have much more than .2" gross lift anyways. Well that sucks. Still wondering about all that smoke though. I first thought a blown head gasket with the bubbles in the radiator. Same cylinder had a wet plug but no deposits (literally just changed them and the oil) ..doh! Might as well change the head gasket while changing the cam right?

Oh, and I first knew something was wrong when it started running hot on the highway. 220* is the maximum it got. Felt sluggish and low on power. I filled the radiator prior to the drive and it is now a little low. The smoke seemed to be white but also a little bluish I think. Wanted to idle high and had a vacuum gauge fluctuation (probably that dead cylinder). #4,6,8 cylinders have good, even compression.
 
Is it a hydraulic cam? If so keep this in mind. Hydraulic lifters can bleed down fast enough that you can't really get a good reading of how much lift your getting unless you use a light checking spring.

Do you have access to a coolant system pressure tester? If so get one and pump up the pressure and see if coolant is leaking somewhere. You could just have a leaking intake gasket. That'll allow oil to be sucked into a port and cause a missfire, erratic vacuum readings, and blue smoke from the oil being burned.
 
Its a solid flat tappet ](*,) MP .528 241/241. I was going to get the same cam unless there is really something better for $200. Maybe a hughes?

I don't have a pressure tester or compressed air. Smoke is defiantly coming from the passenger exhaust though I have H-pipe duals. It smokes a little at idle. I took off 4 intake bolts on the drivers side to remove the factory kickdown, throttle linkage setup and installed a lokar kit. I torqued the bolts back to specs.

I also noticed a little coolant pool on top of the drivers intake. It was in the center by the carb and on the foreward end valleys. I may just have multiple problems?? I'd like to do a leakdown test but again..no air. I can go on base to a shop that has a pressure tester and a leakdown tester but I'd really hate to drive it with the cam the way it is.
 
If the intake valve isn't opening much, it creates tremendous vacuum in that cylinder, and if it can't pull through the closed intake valve, it'll pull oil up past the rings, and down the guides,, that'll cause your smoking out the exhaust..
 
Ah I get it.. then the oil that was pulled past the rings doesn't get burnt but gets thrown into the hot header and hence the smoke. What about the bubbles in the radiator..I'm still going to have to pressure test it to make sure. Knowing my luck I'll change the cam and it'll smoke a ton and not run right or overheat on break-in and I'll have to drive it off a cliff lol This stuff can be so frustrating sometimes.
 
no, it burns and smokes.lol

that is a good cam, i have one in my 340...and $200 cam & lifters...you cant beat that with most cams by themselves costing over $140 alone.
 
Assume it's an issue and pull the head. It could be something like it losened and the piston bent the valve, or a pushrod bent, or whatever, but a non-sealing cooling system means you really need to disasseble carefully and inspect everything. It may be much more.
 
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