440 motor: Bent #1, intake and exhaust pushrods

Author Topic: 440 motor: Bent #1, intake and exhaust pushrods  (Read 7747 times)

Offline RzeroB

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Re: 440 motor: Bent #1, intake and exhaust pushrods
« Reply #15 on: September 17, 2014 - 04:57:27 PM »
what would bend the valves then?   :clueless:

I'm assuming that the failed part of the piston, or "slug" as the OP referred to it as, rattled around inside of the combustion chamber and got caught either between the open valve and the valve seat, or, between the open valve and the piston crown in the quench area. :dunno:
Cheers!
Tom
St Louis, MO

Former owner of 16 classic Mopars. "It is better to have owned (Mopars) and lost then to have never owned at all" (apologies to Alfred Lord Tennyson)




Offline dutch

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Re: 440 motor: Bent #1, intake and exhaust pushrods
« Reply #16 on: September 17, 2014 - 04:59:28 PM »
wouldn`t you expect it to just melt and drop down?  or is that a stupid thought  :dunno:
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Offline Chryco Psycho

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Re: 440 motor: Bent #1, intake and exhaust pushrods
« Reply #17 on: September 17, 2014 - 05:04:45 PM »
I would assume the pert of the piston that came apart jammed between the good part of the piston & the valves

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Offline DocMel

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Re: 440 motor: Bent #1, intake and exhaust pushrods
« Reply #18 on: September 17, 2014 - 05:17:25 PM »
The logic is the cylinder head leak near the lip of the intake where the runner  meets the head causes air to come in the combustion chamber(in this case, #1) at a very lean mixture causing very high combustion area temps.  Bent valve was most likely caused by the piece of the piston face that cooked/broke off

Offline roadman5312

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Re: 440 motor: Bent #1, intake and exhaust pushrods
« Reply #19 on: September 17, 2014 - 05:21:11 PM »
The logic is the cylinder head leak near the lip of the intake where the runner  meets the head causes air to come in the combustion chamber(in this case, #1) at a very lean mixture causing very high combustion area temps.  Bent valve was most likely caused by the piece of the piston face that cooked/broke off

Thats what I was thinking, vacuum leak #1. Thanks for sharing.   :cheers:

Offline RzeroB

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Re: 440 motor: Bent #1, intake and exhaust pushrods
« Reply #20 on: September 17, 2014 - 05:26:32 PM »
The logic is the cylinder head leak near the lip of the intake where the runner  meets the head causes air to come in the combustion chamber(in this case, #1) at a very lean mixture causing very high combustion area temps.

An intake leak?

An intake leak creating an overly lean mixture which overheated the piston to the point of failure? Ok, that sounds plausible. Wasn't sure what was implied with "cylinder head leak" - I was thinking you were referring to a head gasket leak. I get it now. Thanks!
Cheers!
Tom
St Louis, MO

Former owner of 16 classic Mopars. "It is better to have owned (Mopars) and lost then to have never owned at all" (apologies to Alfred Lord Tennyson)

Offline DocMel

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Re: 440 motor: Bent #1, intake and exhaust pushrods
« Reply #21 on: September 18, 2014 - 09:35:01 AM »
Yeah, I get it   Myself, when the machinist and I were taking a look and he said cylinder head leak/blown gasket, I was looking for signs of coolant cross over, what I typically associate with a blown head gasket.  Instead he said, “here’s your cross leak area”:  I could actually feel the slight depression between the intake runner and the combustion area

The top of number one piston is really fried.   Sure wish I had caught it in time

Im in the process of having the short block work done now.   I had been running 68 dated RB heads, but I just ordered a set of 440 source heads along with  E brock intake and a mild cam.    Im not a looking at a serious engine build. 

I prefer these days a better breather and solid road manners

Intake will be the E Brock, Performer RPM, Dual Plane intake, Aluminum

I dont have the cam specs with me now but power band will be in the 1400-5000 rpm range   Once I get the specs Ill post them