7.3 IDI Oil Cooler Rear Header

[Knuckledragger]

Cavitation is most prevalent in the 7.3 IDI engines. When Ford decided to offer larger displacement, they neglected to change the tooling to keep a nice thick cylinder wall. They just bored out the 6.9 casting, thinking like gassers ("there is enough wall thickness, let's just bore it out!).

Electrolysis does not happen in distilled water. Water by itself has no ability to conduct, but adding almost anything into solution will create an electrolyte. Gary is mostly true in that distilled water will not cause electrolysis, but the very act of adding it to the cooling system will add electrolytes because water will carry off ions of iron, aluminum and brass while doing its job as coolant. If you want to speed up the process, add salt. That makes a great electrolyte. Baking soda does a good job, too.

 

[Wvdirtroad]

if it is a roller lifter, yes pulling the covers off and wiggling the rockers, making sure there all nice and tight will work.

if you see one thats obvious it has lots of play, you found another issue to address.

So im currently looking over some head diagrams and so forth and It looks like if its a hydraulic roller lifter they are down in the valley area of the block and seem like they'd be a challenge to get to. Is there anyway to tell if they are bad without taking them out of the block to inspect? I know you mentioned wiggling the rockers to see if they are tight etc, but wouldn't that just tell me if the rockers/ springs have something wrong with them?

 

[IDIoit]

if a lifter is collapsed, you will have alot of play in the pushrod.
this will tell you if you have an issue in a fubard lifter(which would also beat up a pushrod) rocker or spring.
pulling the intake, and valley pan isnt hard, but if youre in there, and you suspect a bad lifter, i would just replace them.

 

[IDIoit]

did you get your parts?

 

[Wvdirtroad]

They are actually due in tomorrow and I plan to reinstall, do coolant, fresh oil, take a look at the lifters, drivers side head gasket, maybe turn up IP one flat and replace fuel filter Friday. Busy day planned!

is there a typical amount of play or will a bad component have noticeably more play than the rest?

 

[IDIoit]

it will be completely noticeable.