Little engine delimma I need help with.

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hemichuck

hemichuck

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not an A body but another project I have going. A few years ago I bought a truck pretty cheap with a blown up 4.7 in it so I pulled it out to replace and couldn't find one for sale so I rebuit it which got pretty costly because it was thoroughly destroyed. To make a long story short, between selling my business and my building and moving all my car stuff around it's ended up just sitting for about 5 years before we got it installed. When we fired it up we have one cylinder that is dead(number6) and I suspect the rings are stuck in that cylinder as a result of my procrastination and some sub par storage facilities so the question is, is there some mirical cure or desperation move I can try to get this cylinder to work before I start tearing into it again? Any practical advice or old car guy tricks would be appreciated.
 
Try some Marvel Mystery Oil in that cylinder. Although I have never done it, I have heard story after story after story about how it worked.
 
Yeah, that was my first thought. I used to know an old guy that was a dealership mechanic all the way back to the 1930's and he was a wealth of knowledge and shortcuts to make things work again. I wish he was still around today.
 
hemichuck said:
not an A body but another project I have going. A few years ago I bought a truck pretty cheap with a blown up 4.7 in it so I pulled it out to replace and couldn't find one for sale so I rebuit it which got pretty costly because it was thoroughly destroyed. To make a long story short, between selling my business and my building and moving all my car stuff around it's ended up just sitting for about 5 years before we got it installed. When we fired it up we have one cylinder that is dead(number6) and I suspect the rings are stuck in that cylinder as a result of my procrastination and some sub par storage facilities so the question is, is there some mirical cure or desperation move I can try to get this cylinder to work before I start tearing into it again? Any practical advice or old car guy tricks would be appreciated.
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Have You checked the compression in that cylinder? What led You to believe that is the issue? Did the rebuild include reboring, if so the rings should have a seal enough to run
on, the "stuck ring" syndrome resulting in a misfire typically happens on an engine w/tapered bores to the rings that sat at the bottom of a cyl. Have You checked for the
injector being stuck/contaminated or clogged, rondentia damaged harness, strong spark at the plug etc.? The screens in some injectors are so fine that water will actually
"plug" them, having set a while, an insect or debris could've entered the fuel rail & ended up in the screen, ........seen it all happen so,.....just some ideas...............
 
Yeah, we got a big zero on the compression check. Motor was completely rebuilt by a very competent shop(who is actually a good buddy of mine) the engine was stored in a barn for a couple of years and the humidity in there was terrible, I was concerned that this would be the result but at the time had nowhere else to store it. Nobody's fault but mine, procrastination is a ***** sometimes.
 
With zero compression I would suspect a valve hung open. Pressurize that culinder with compressed air and listen to the intake and exhaust for leaking air....
 
hemichuck said:
not an A body but another project I have going. A few years ago I bought a truck pretty cheap with a blown up 4.7 in it so I pulled it out to replace and couldn't find one for sale so I rebuit it which got pretty costly because it was thoroughly destroyed. To make a long story short, between selling my business and my building and moving all my car stuff around it's ended up just sitting for about 5 years before we got it installed. When we fired it up we have one cylinder that is dead(number6) and I suspect the rings are stuck in that cylinder as a result of my procrastination and some sub par storage facilities so the question is, is there some mirical cure or desperation move I can try to get this cylinder to work before I start tearing into it again? Any practical advice or old car guy tricks would be appreciated.
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A 360 or a 5.9 magnum should be pretty cheap at a pic-and-pull. Easier too.
 
"With zero compression I would suspect a valve hung open. Pressurize that cylinder with compressed air and listen to the intake and exhaust for leaking air...."

I agree with 55Dave here, "0" compression=stuck valve, leak down testers are in the same dept as compression testers and almost as cheap to buy and a must in every tool box, if the valve is stuck the Mercury Power Tune mentioned earlier by joesbp dose work very well, I actually am a Mercury Dealer and use it all the time, I also have used the Marvel Mystery oil and it works well for stuck valves too
 
I would pull the valve cover and see if it threw off a rocker arm or there may be too much lash and need a shim under the lifter. Kim
 
oldkimmer said:
I would pull the valve cover and see if it threw off a rocker arm or there may be too much lash and need a shim under the lifter. Kim
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^^^^^^^ this would be my first check they usually don't hold the valve open when they spit a rocker out but I seen it before once .
 
All of the above possible, and possibly true. If the valve was hung open the rocker would be easy to throw after the fact, pull the cover & check them. Hopefully if a valve
hung open it didn't get clipped by the piston or..............................
 
Thanks for all the suggestions except the one about buying a cheap 5.2 or 5.9, not easy to replace a 4.7 with a magnum, complete different wiring, computer and transmission.
 
Ottmundr said:
A 360 or a 5.9 magnum should be pretty cheap at a pic-and-pull. Easier too.
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Not an easy swap in a 4.7 truck, different wiring,computer,transmission, and exhaust. If it were that easy I would have installed one of the 408's I have in the garage in it already.
 
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