Rebuild or...

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josh
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Re: Rebuild or...

Post by josh » Sun 22. Apr 2012, 15:19

Update:

So, after taking the top and front of the engine off, the only real damage I found was to the timing chain and the pushrods. I replaced the gears and chain, then cleaned the bits of Teflon out of the oil pan. All that is left is replacing the pushrods and putting the rest of the engine back together. I'm a bit wary that I may be missing something in all of this, so I'll just ask. Could the combination of a very bad timing set plus over revving been what caused the pushrods to bend? If that is a yes, then I can breathe easy for once. If not, let me know what I'm overlooking.

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Josh

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Theo
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Re: Rebuild or...

Post by Theo » Sun 22. Apr 2012, 16:14

Overreving? What cam do you use? No overreving w. a stock cam IMO. But a shot timing chain plus lazy valve springs can cause the pistons to hit the valves before they had the chance to seat. The valve tips would transfer the force to the rocker arms and the push rods. Your valve seats, valve guides and the valves themselves could be worn or damaged too. Did you check all that for signs of wear or damage?
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josh
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Re: Rebuild or...

Post by josh » Sun 22. Apr 2012, 16:58

Everything is stock. I checked everything out according to the manual as best as I could (meaning, I did exactly what the manual said) and it all appeared to be within spec. Just a few bent pushrods and a bad timing set. Should I take the heads off again and take them to a shop to have them gone over by a professional before I proceed?

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josh

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Theo
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Re: Rebuild or...

Post by Theo » Sun 22. Apr 2012, 18:13

Hard to tell. The machine shop will most likely find s.th. That's how they make a living for. Maybe you should try to inspect the heads all by yourself first. You'll need a spring compressing tool. Lay out the valves, springs and locks on a card board and make sure to mark them according to their location. All components should be reassembled together w. their corresponding components and right into the same location it came from.
If you feel insecure or feel that you might mess up things you'll still have the option to take it all to a trusted mach8ine shop.
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josh
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Re: Rebuild or...

Post by josh » Sun 22. Apr 2012, 18:27

Okay. Will do.

Heh. The hardest part, of course, is overcoming my enthusiasm for getting it back on the road as soon as possible. But, I'd rather take a couple more days to check everything out again than go to start it up only to find that I have to take it all back apart.

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Josh

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Theo
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Re: Rebuild or...

Post by Theo » Mon 23. Apr 2012, 01:54

Check for valve guide wear by wiggeling the valves in the guides once you took off the springs. Also take a look at the valve seats. I highly recommend to purchase adjustable rocker arms. They're your best friend and once installed w. the right lifter pre load they will correct imperfect valve train geometry such as too long or too short pushrods etc. They're usually sold as FE aftermarket parts. You might also run into good used original adj. rocker arms that come out of an FE truck or FE police car. If you can't steal them cheap just buy the Harland Sharp. They're great rocker arms for the money. Dunno if they interfere w. your valve covers. I forgot , maybe some other participant will tell you.
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