cracked block or cracked head

What are the results of a cracked block and also head? are there differences?

Reply to
spider
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Differences? If the vehicle is not too old one can be economically replaced the other can not, for one.

mike hunt

spider wrote:

Reply to
MelvinGibson

Reply to
spider

A cracked block will generally either leak coolant onto the ground, or less commonly, into the oil. A severely cracked block (that's taken a really big hit) can cause the crankshaft to break if the bearings are missaligned. If its a small crack in the block exterior wall, it can sometimes be fixed by grinding a V slot and applying JB Weld.

A cracked head can

- leak exhaust into the coolant, causing a boil over

- leak coolant into the oil, or vice versa or both, causing boiling or bearing failure.

- cause valve seats to drop out if its cracked between the valves.

Can only be fixed by replacing the head.

Stewart DIBBS

Reply to
Stewart DIBBS

The repair will cost you more than the vehicle is worth.

mike hunt

spider wrote:

Reply to
MajorDomo

The truck is in amazing shape(no rust) there is oil in the rad but no coolant in the oil. I know the head gasket went but I am just trying to figure out if the block cracked or the head. Thanks for your help:)

Reply to
spider

Could just as likely be that neither one is cracked - head gaskets can just let go because of several little things like bad cooling system care, or just because they feel like it. Take it apart and look /before/ you panic. ;-P

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Reply to
Bruce L. Bergman

I took it apart and replaced the head gasket(one was really bad), checked for cracks and made sure the head was not warp. But couldn't find any cracks. put it back together and still oil in the rad. hmmm:(

Reply to
spider

How did you check the headds for warpage? did yuou take it to a shop? This is the only real way to check. BTW, anybody, do they still do magnafluxing, or was that in the days of iron heads?

Reply to
hachiroku

"" wrote: > Differences? If the vehicle is not too old one can be > economically replaced the other can not, for one. > > > mike hunt > > > > spider wrote: > > > > What are the results of a cracked block and also head? are > there > > differences?

Not exactly, I had a cracked engine block for a old Ford tractor fixed once and that was over 25 years ago and that tractor still runs today. (good blocks for those were kinda rare then and even more so today)

Reply to
SnoMan

Not true if it is a aluminum head, I have seen some nasty ones fixed and one nice thing about aluminum heads too. Cast iron heads are generally trashed though.

Reply to
SnoMan

Head gasket do not just blow for no reason, when they do, 99% of the time it is because the engine has gotten to warm once or twice and the head has warped causing uneven pressure on head gasket and swtting the stage for it to blow.

Reply to
SnoMan

You likely have a crack in head other than surface area or in the block itself. You should have had the head pressure tested at the proper place. There is a chance that block is cracked but not likley. Over 90% of the time it is in the head(s)

Reply to
SnoMan

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