Piston pin bad ?

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Don't forget to run the engine oil thru a paint type filter to see what's in it, good luck getting this back together
 
this picture makes me wonder if you had an intake or head gasket leaking water into the engine..

I recently built a 340 that leaked water into the engine thru the intake gaskets.

Was all new parts on top of a good tested 340 block with edelbrock heads.

Ended up the gaskets weren't thick enough for this setup.

I looked around for thicker gaskets and ended up stacking up two stock felpro gaskets.

When looking down the intake bolt holes they looked just a little high and were perfect when torqued down.

Luckly I never started the engine and found water in the oil first , dumped the oil and filter and put in new before firing it up for the first time.

Mine had similar stains like yours in the valley , but nowhere as bad as yours.. Again good luck with this
 

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Heads were not on during storage. Besides I didnt have cam installed until a few months ago... So the valves would have been seated.
 
And somewhere back you seemed to sense/joke about a foriegn object in the intake mainifold,, that could still have been true.. food for thought..
 
SGBARRACUDA said:
Did the Rockers seize to the shafts? Are they galled up?
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mbaird said:
oh yeah ....I havent pulled the drivers bank yet but all the pass. side ones are galled to a point... the #8s will barely move !

I will call Hughes in the morning .

The clearance between the shafts and the rockers were super tight.
I thought it was pretty impressive at the time , but now that I think about it I am not sure that is a good thing... Aluminum and hardened steel expand and contract at different rates...right?
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I was hoping you were going to find an easy/inexpensive solution here. Rockers seized to the shaft and valves hung up causing piston to valve slap??
I guess you didnt run engine long enuf with valve covers off to chk and see if the rockers were binding??
 
I used stethescope in vavlecover when I had a ringing sound from slinger.. It was quiet then. Never thought to check valvetrain again after knocks developed.
 
I did have the vavlecover off while running but never thought to check valve at that point since I had already eliminated them. Besides by that point the knock awas so loud it was hard to tell where it was coming from.
 
Ok. Nobody else has said it, but I got to. That valve job is about the shittiest I have ever seen. Especially on the exhaust side. Both the intake and exhaust seats are WAY too wide. Not that any of that has anything to do with the noise, but I'll be DAMNED if I would run those heads on anything.
 
inertia - I don't like the look of the exh seat given I think it's been exhausting and chomping on piston material but I don't see marks where anything but aluminum might have gotten caught in there. I also agree on the water damage theory. It doesn't normally look like that and isn't completely accross the top of the piston unless there was enough water to completely cover it... But that would leak out over time depending where the ring gaps ended up.
Like RRR said - that's some "backyardy" head work. It's hard to see but I don't think they are more than 2 angles on either intake or exhaust and the seat replacement work isn't really good either. It makes it hard to trust the other parts of the valve job that effect goemetry and the rockers. The top end is a mess, the bottom end is a symptom of that. At least IMO.
 
Inertia-- the one thing I noticed before you posted about that exhaust seat was that it is not looking evenly worn or finished. I would be looking at #8 valve stems very carefuly to see if they are bent even the smallest amount; that could have started the whole thing.

I just dunno about the water idea anymore....I'm more thinking the valve(s) bound, and the valves chipped the eybrows as can bee seen and the bits started flying. The valves binding and the pistons to hitting could possible cause the wear on the rockers surfaces, and especially distort the soft AL body of the #8 rockers, which were reportedly almost not moving at dissassembly. (But hey, it took me 10 years to figure out the cause of a particular bore distortion so what do I know! lol)

BTW, what kind of oil was being used here?

And to the OP, not picking ya at all but making an observation. One of the first things I noticed in the piston-in-bore pix was the almost mirror-like finish on the bores; that is not normal looking in my experenince in new bore finishes. I always use moly rings so thesebores may be finished for something else like chrome rings, but I only see that smooth of a bore finish after a lot of cylinder wear.....
 
inertia said:
PS ..can someone give me an opinion on the ex. seat post 87, I think.. Might just be my eyes again..
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RustyRatRod said:
Ok. Nobody else has said it, but I got to. That valve job is about the shittiest I have ever seen. Especially on the exhaust side. Both the intake and exhaust seats are WAY too wide. Not that any of that has anything to do with the noise, but I'll be DAMNED if I would run those heads on anything.
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Thanks, - That's what I thought I was seeing..

nm9stheham said:
Inertia--
I just dunno about the water idea anymore....I'm more thinking the valve(s) bound, and the valves chipped the eybrows as can bee seen and the bits started flying. ..
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That's one possibility

moper said:
inertia - I don't like the look of the exh seat given I think it's been exhausting and chomping on piston material but I don't see marks where anything but aluminum might have gotten caught in there. I also agree on the water damage theory. It doesn't normally look like that and isn't completely accross the top of the piston unless there was enough water to completeover it... But that would leak out over time depending where the ring gaps ended up.
Like RRR said - that's some "backyardy" head work. It's hard to see but I don't think they are more than 2 angles on either intake or exhaust and the seat replacement work isn't really good either. It makes it hard to trust the other parts of the valve job that effect goemetry and the rockers. The top end is a mess, the bottom end is a symptom of that. At least IMO.
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I noticed the nicks in the seat as well, it wil need touching up, but my concern was stated by RRR..

hope it helps
 
Valves came out of head nicely... point on vavlejob taken and might have another shop look at them . .. but the shop that did them is one of the premier builders around here.
I doubt the valve job had anything to do with the failures since the engine has not seen much more than 3500 rpm so far. performance down the road might be a different story !

no worries about the critique ... I like a straight answer.
 
BTW, thanks for sharing all the pix and the story...there is always stuff to learn. And guys ALWAYS like to talk engines!
 
Thanks ,

I was running Joe Gibbs breakin oil. Preheated before starting.

I emailed Hughes with pics and description. Dave emailed back and asked me to send rockers and shafts back. It's one thing to have a defect in a product (stuff happens! ) it's how the manufacturer reacts to the problem. And this seems to be a good sign.
 
mbaird said:
Thanks ,

I was running Joe Gibbs breakin oil. Preheated before starting.

I emailed Hughes with pics and description. Dave emailed back and asked me to send rockers and shafts back. It's one thing to have a defect in a product (stuff happens! ) it's how the manufacturer reacts to the problem. And this seems to be a good sign.
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Definitely a good sign!
 
Not to throw rocks at your parade, but a good sign is when they send you new replacements for free. The fact that they want you to send them back is to appear to show good will, before they smash your balls between two rocks! Maybe I'm being a pessimist?
 
Blues are hot this year! As are the bruins... Whats up with your teams ? I grew up in MN but the Canadiens were my heroes! and Bobby Orr... It just pains me to see them in a slump!
 
Leafs are my team...and I wont apologize for it! LOL
Im hoping for the Blues this year. A team that has never won and has a few ex Leafs on the team. Steen for one, scored the OT winner tonite.
Bobby Orr was one of mine as well. He grew up about 1 1/2 hours from me(Parry Sound) I spent 2 summers as a teen working about 10 minutes from Parry sound.
 
I used to play against and (with on occasion ) a guy I knew as Johnny Mac that had 2 Cup rings playing with the Leafs. He must have played in the 60s but still had it !

Also played with Rick Bourbanais that played for the Blues . Younger than Johnny and really good.
 
Have also played with Brett Hulls brother (Bobbys other son) . He was good but never made it to the NHL , just semipro....
 
C'mon guys, when the Red Wings get started on the Bruins tonight, it'll all be over for the rest....lol. 23 playoffs in a row and counting....
 
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