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crankcase pressure test

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I am trying to run a crankcase pressure test on 08 250.  i do not have the tool the book calls for, 303-758. i found one in the shop that i believe is used on the 7.3. i was told it would wok but i am questioning it.  the complaint on the truck is that it has oil consumption. i have checked relative compression and power balance and checks ok. fuel trims are less than 2 on all cylinders. i have not checked manual compression.  with the old crankcase tester i have 5 psi blowby. would this be accurate  or should i make the shop get the correct tool?

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I think those crank case pressure test adapters are engine specific but the 6.0L and 6.4L do use the same adapter. The obvious difference is the type of mount used to connect to the oil fill but there is an orifice in all of them that is likely different and will affect the reading. With that said, the 7.3L adapter will likely provide you with skewed readings even if you can screw it on. Somebody correct me if I am wrong.

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Thanks for the reply. I figured they were different but I was under the impression that the previous tech used this tool but I did not think I was getting the correct results.

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You could build one. The orfice hole size would be the only critical measurement. I (Or someone that has one handy?) could measure the hole size for you.

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I was told in class that you can use the 7.3 adapter on the 6.0 and 6.4 and the other way around you just need to use the specs for the adapter you are using since the holes are different sizes.

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They made the holes smaller for the 6L and 6.4L so as to provide a more accurate reading. Use the 7.3L specs. Remember to disconnect the CAC tubes to eliminate the chance of a bad turbo messing the readings as well. If you are pushing 5 inches with the 7.3 adapter, I would say you have an issue. 3" is max for a 7.3L.

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