Compression check

[adic27]

Anyone ever had to perform a compression test on their bus? I want to do one on a 1998 Navistar dt466e. Where would one acquire the "special tool" needed. I checked autozone and O'Reilly's but they don't have one for diesel engines. I have this compression test guage. Could it be used if I find the adapter, or what a guy called a "dummy injector" in a YT video I watched?

Thanks

[cadillackid]

yeah for the 466E you pretty much must haver the "dummy injector" and you need to make sure that you drain the head first and clear the cylinder of ALL liquids first before performing a compression test.. even a small amount of oil in a cylinder will throw a compression test off. (oil can seal around sloppy rings) esp if you are looking to validate thoughts of bad rings..



you'll want to leave the drain plugs out as the head will try and refill with fuel and oil each time you crank over the engine.



when you pull out HEUI injectors the oil and fuel in the head rails will fill up the cylinders.. the most happens on the first one you pull... but a little can still go down even on subsequent cylinders..


the link you posted is a battery charger..


you need a diesel compression tester that can read the high compression... 466E are usually in the 320-360 range so your gauge needs to be able to read that..

[adic27]

My bad lol, linked wrong thing

Gauge

[cadillackid]

Originally Posted by adic27

My bad lol, linked wrong thing

Gauge

that one maxes at 300, not good for a diesel.. your compressions will (should) be in the 320-360 range on a healthy 466E