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-   -   Show and tell (https://www.racingjunk.com/forums/showthread.php?t=17523)

mytmouz 06-09-2007 08:11 PM

Show and tell
 
Well I've got to pull me engine and do a tear down inspection. Give your opinion as to what's wrong, and when I get it out we will see. :( I've got an iron block/aluminum headed small block. It has head studs which are sealed, oringed heads/reciever grooved block, copper head gaskets that were retorqued after the 2nd heat cycle. (six passes now). The block is partially block filled. When I dropped the pan to fix an oil leak, I noticed water dripping between the # 4 piston skirt and the cylinder wall. When I rotated the crank to look in the bottom of the cylinder (it was at the bottom of the stroke) water ran out of the header when the exhaust valve open. It did not run hot (over 180) at any time and the water was not mixed with the oil. What's your guess? I'm going with a cracked cylinder as that's the way my luck goes.

zipper06 06-09-2007 11:46 PM

Well Neighbor,
Either way it doesn't sound good. I thought you had a Dart lillte "M" blk in the truck, which at 4.125 bore should never crack.
Which ever way it goes let us know.

Zip.

davis419b 06-10-2007 05:42 AM

If the block was a Dart it probably would not have grout in it. I bet it is a GM 400 and i am going with a cracked cylinder wall. I have had it happen in the 10 tears i ran a 377 sbc,

mytmouz 06-10-2007 07:54 AM

It's factory GM, sorry I left that out. However it turns out, I'm gonna go aftermarket this time. *$@# budget racing. :lol:

jaykz1000 06-10-2007 11:29 AM

yep i had a 509 block ran it for 2 years had cometic gaskets on it always thought they leaked some over night... so i just drained the radiator after racing and went on with it ... then i had to take engine apart one day and found i had a hair line crack in one of the cylinder walls toward the lifter bores... it was about 3 inchs long... u could barely even see it ...been runnin it like that for 2 years .lol thank god it wasnt on the thrust side.. prolly tore up everything heck i ran compression and all on this engine many times and it was fine... i have had many 350 block crack and u can tell when they did be a wide crack...

knova70 06-10-2007 04:08 PM

I guarantee it was cracked at the steam hole,usually the top one and after it cracks from the stress of the head stud and cylinder pressure,then the crack starts to run down the cylinder wall,after taking my 400 apart for the same reason that was what it was,and it cracked on every top steam hole but only 2 cylinders were cracked,and this was a virgin block with only about 30 passes on it,it was maged before it was machined,but thats what I get for using a stock block! went to a bowtie aluminum block as of now hope this one doesn't crack?

jaykz1000 06-10-2007 05:03 PM

my holes where plugged and then decked

knova70 06-10-2007 05:20 PM

they still will crack,doesn't matter what you do to them,just personal experience.

jaykz1000 06-11-2007 01:47 PM

never said they wouldnt just statin that they can crack any where anyway...

bjuice 06-11-2007 03:07 PM

have the heads had any work done to them ?..i have seen over agreesive port work done where the exhaust valve bowl developed a hair line crack..you could not see by looking at it...i did a backyard pressure test..DAWN dishwashing liquid and a air pressure hose...showed right up.

it did not run hot..when the motor got warm the crack in the heads would expand and leak fluid into the #8 cylinder..after it sat for a while the cylinder would fill up...

if there was any epoxy work done to the heads it could have come loose...SO DO NOT PUT ALL THE EGGS IN THE BASKET ON THE BLOCK BEING BAD AT THIS POINT..

brian


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