a couple problems with rebuilt 400
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From: Nebraska
a couple problems with rebuilt 400
I'm having a couple issues with my newly built 400. With about 250 miles on it I broke a rocker arm bolt. This was after coming off the highway probably 2600 rpms. I got that fixed and it's running again, but I'm hearing a ticking sound coming from that area. You won't hear it on a cold start, but it gets louder as the engine warms up. What could have caused the bolt to break? And I'm pretty sure the tick has to be related. This didn't happen from abuse either, I've taken it fairly easy so far.
I'm also getting a puff of smoke if I wind it up to probably 3000 and upshift. This is also possible in neutral snapping the throttle, though not near as noticable.
Other than that it runs great. I'm very impressed with the power, and this is with just a bigger cam and 4 barrel intake. It would run circles around my old wore out 460.
I'd love to see how some of your more modified engines run.
I'm also getting a puff of smoke if I wind it up to probably 3000 and upshift. This is also possible in neutral snapping the throttle, though not near as noticable.
Other than that it runs great. I'm very impressed with the power, and this is with just a bigger cam and 4 barrel intake. It would run circles around my old wore out 460.
I'd love to see how some of your more modified engines run.
Last edited by brown 4x4; Apr 3, 2005 at 11:53 AM.
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Joined: Feb 2004
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From: e-burg
the ticking sound could be from a pushrod that is to short or posibly bent(kind guessing here)
now the blue smoke i think i can answer. the most likely reason is the rings havent "seated" yet so u will get blue smoke just as if rings where worn out
hope that helps
now the blue smoke i think i can answer. the most likely reason is the rings havent "seated" yet so u will get blue smoke just as if rings where worn out
hope that helps
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Joined: Sep 2001
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Did you check the lifter preload on all of your valves when you assembled the engine? Did you check for coil bind etc? A damaged valve seal can also cause a puff of smoke like that. Improper valvetrain geometry or over torquing the bolt can cause failures.
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From: Nebraska
What exactly do you mean by checking lifter preload? I did check the installed height for my coil springs. I torqued all my rocker arms to spec from my Ford CD.
As for the valve seals, the machine shop gave me Teflon seals, I can't remember what he called them. They were kind of a pain to put on and real easy to damage. It's probably not going to be too easy to tell which one is bad? I'm only noticing the puff out of the drivers side, but I can't see the other side as well either.
As for the valve seals, the machine shop gave me Teflon seals, I can't remember what he called them. They were kind of a pain to put on and real easy to damage. It's probably not going to be too easy to tell which one is bad? I'm only noticing the puff out of the drivers side, but I can't see the other side as well either.
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OOOoopppss the problem may have been found. 
The cam may have come with instructions. You can also go to the cam manufacturers website. A service manual usually has instructions and so do engine rebuild manuals. The entire valvetrain geometry must be checked when rebuilding an engine. The block and head get machined during a rebuild plus the new parts all have tolerances. Hope you did not mess up the cam, you might have tho...
The cam may have come with instructions. You can also go to the cam manufacturers website. A service manual usually has instructions and so do engine rebuild manuals. The entire valvetrain geometry must be checked when rebuilding an engine. The block and head get machined during a rebuild plus the new parts all have tolerances. Hope you did not mess up the cam, you might have tho...
