7.3 idi factory turbo loud knock noise

Thewespaul

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This is a good and bad news. Push rods are cheap but usually they bend for a reason, hopefully it wasn’t because a valve hit a piston, but that’s usually the case.
 

1978FrankenFord

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Im hoping that that didnt happen. I was curious if the owner before me were to lock it using either, because i know he tried but couldn't get it to run. Would the bent rod also cause the squeak noise along with the knock? I know it causes knock but im not sure on the squeak
 

IDIBRONCO

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It's hard to tell on that. If you want to check those push rods without pulling the engine, theen you'll have to remove at least part of the HVAC box.
 

Macrobb

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Honestly, if the half you can see is straight, it's fine. The lifters will take up quite a bit of slack; it takes a seriously bent pushrod to be a problem.
 

1978FrankenFord

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Ya the 2 looked fine. Im more worried on the one that was bent, if i put on a flat surface there is about an 1/8th inch gap between the flat surface and the middle of the pushrod. Would this be enough to to make the knock and squeal? Because if not then it could be a bigger issue
 

1978FrankenFord

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Thats what i thinking. Hopefully it fixes it lol. Ill keep you guya updated. Parts dont come in till next week so we shall see
 

icanfixall

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Well you appear to have found the issue but.. Finding out why this happened needs to be before you run this engine again. Usually just replacing bent pushrods and not fixing the reason they bent will cause it to happen again.Try laying a straight edge along the tops of the valves. See if any of the valves with bent pushrods are lower than the others with no bent rods. That "may" show a bent valve if a valve contacted the piston. You are moving in the correct direction to fix this too.
 

1978FrankenFord

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Icanfixall, thats a good idea i never thought about running a straight edge on the top of the valves. Good idea, ill give that a try!
 

Macrobb

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Just be aware that it's really unlikely to have a bent valve. The piston is square to the valve, so it'll smack it straight back up the guide without bending anything if it does hit.
Typically, if you do have a little valve-piston contact(over time), it will just destroy the guide.
I have pictures of this, and a head that needs a new guide.
 

1978FrankenFord

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I finally got around to putting the rods in and i rebuilt the turbo. Now it makes this aweful squeak noise. I took the belts off and its not an accessory. Here is a video of it.
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Thewespaul

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Holy moly that’s a bad sound. Almost sounds like a lifter turned or something, but definitely metal on metal.
 

Thewespaul

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I said it my first post and I’ll remind you again. Start looking for another engine, I have a complete idi turbo pullout if you want to travel south, but that’s not an easy fix kind of sound.
 

Macrobb

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Edit:
Wrong topic. Ignore this post.

Well... no. I'm going to run it until it either sounds horrible, or next year. I have an (in good shape) '88 pullout from this truck that just needs head gaskets, and that will go in my tan '88 as I build it towards 300+ at the wheels. Once that's running good, I'll tear into this one. Still really thinking it's lifters/valve-train, though... just doesn't act like a rod knock - no change under varying load.
 
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