Powerstroked162
On Da Juice
Yes what? lol
All I got to say..
- Thread starter MadDiesel73
- Start date
Yes what? lol
Vader's Fury
Active member
rod came out.... block spider webbed right where the pan bolts on.......
Which came first, the chicken or the egg?
Which came first, the chicken or the egg?
TrailerHauler
New member
Good question
MadDiesel73
New member
Looks like what you said about hydro fracture. But the rod let go at the same time.. So was It just the rod that went or did the hydro fracture cause the rod to go?
Im being.an ass Steve. Whether the rod busted that or it busted and let a rod go it appears there was a structural failure in and around the pan seat. Its pretty gruesome to look at. The fact its cracked all around the pan seat/rail is pretty telling.
I feel pretty bad for the op as he just got this truck going. Its a nice daily driver of a truck.
Well mads, if you hydro.fractured it then the block would have been moving around. Stress on the rod from movement and Boom. Its prett hard to doubt fracturing looking.at the broken glass appearance of the block right there.
Last edited:
Powerstroked162
On Da Juice
Im being an ass too because I specifically stated in the original build thread to NOT do the pan job in frame for these very reasons and I was blown off like I was speaking klingon or something. I still feel bad for the OP because he really didn't know any better to believe what I had to say and this chit happened to him when he was having fun with his toy. Thats a confidence killer for most. Kudos for keeping after it!
Ohhhh, I remember. To be honest, first thing I thought of.when I saw this thread. I did one of these
MadDiesel73
New member
:wtf::shocked:uke::doh:
uke::doh:
Hotrodtractor
Moderator
You want adequate clearance for the piston to the head not to make contact- but you also want to keep that as tight as possible to improve your quench and consequently improve your combustion efficiency.
MadDiesel73
New member
What's optimal pth clearance?
97powerstroke
New member
So how do you hydro fracture a block and what do you do to avoid it?
Powerstroked162
On Da Juice
Talks about it a little in this thread. Starts at post #77
http://powerstrokearmy.com/forums/showthread.php?t=18310
Basically its from getting residual silicone and/or the new pan sealant onto the pan bolts or into the pan bolt holes and then tightening up the bolts in sequence creating a mini hydraulic press effect in each bolt hole, if you will. The force can be enough to hairline fracture and even crack the block immediately. It's a chit deal
Hotrodtractor
Moderator
Good question without an easy answer. You want the piston to head clearance to basically be minimized right down to the point so when the engine is running that the piston just BARELY doesn't hit the head. This number is a stack up of MANY variables - if you say increase the rod bearing clearances - you now need to increase the piston to head clearance, you install a heavier rod - again increase in clearance, you want to rap it out at a higher RPM - that causes more rod stretch so you need more clearance, etc...... So in the end its a combination that whoever is building your engine needs to come up with so they can take into account the clearances and tolerances that they are building your engine to as well as the components of your specific build.
When in doubt - err on the large side of the most clearance possible. Factory spec is 0.010-0.031" piston protrusion - minimize the protrusion to get the most clearance possible. I feel that 0.050" piston to head clearance is "safe" for most people to build to. I go a little tighter than that on the combo of parts that I know and feel safe with - but the next motor I plan on opening it up a little more BECAUSE of another tolerance change in a different component that I am also opening up for a different reason. Its a vicious cycle. LOL
SEABEE08FX4
New member
That sucks for sure, look at Manley for a set of rods though. I believe they have a set that is more reasonably priced than say Crower or Carrillo.
Hotrodtractor
Moderator
Manley rods don't actually exist yet.
Hotrodtractor
Moderator
On a side note has anyone purchased a set of Carrillo rods for a 7.3 with the forced pin oiling option?
SEABEE08FX4
New member
Wasn't aware of that, I was talking with David Lott about them the other day but didn't realize they we're not producing them yet. Sounds like they will be much less expensive than the other options. HP rating I believe was in the 900-1000 range, made from 300M just for those who were wondering.
PowerstrokeJunkie
Active member
before everyone goes and blames some silicone for cracking the block, shouldn't Mad check to see if the rod broke first and shoved the block out? :shrug:
lol..
no kidding...
that line of thinking is almost comical..
cryo'd rods have proven to be as reliable as stock forged rods...ie.. hit or miss at levels above 450hp.
anyone that BUILDS an engine..from the ground up...WITH plans of making more than 450-500hp..and uses a forged rod is simply rolling the dice.
this is very very different than taking a bone stock forged rod engine and bolting 10g's worth of hot rod chit on it..and going out and making 650rwhp...because there is next to nothing invested in the actual rotating assembly.
if it blows the eff up...big whoop...but to build an engine for anywhere near this type of power level (with forged rods) is....reckless, IMO
Powerstroked162
On Da Juice
I must have missed what was funny about the block cracking from that exact scenario?? I never said it was the cause either, I'm just saying the picture doesn't look to good
Last edited:
Members online
No members online now.