How much blow-by is normal? The top of my front rear looks like a sludge dam. Is there a fix or some sort of test that can be done?

Rick

 

You need a blowby tool. For those who don't know what a blowby orifice tool looks like, it's a tee with one .221" (15/64-in) outlet. Connect one end of the tee to the end of the blowby tube. Put a manometer on last tee outlet. That is your blowby tool. They sell them at the Cummins, but I have made my own plenty of times. A simple manometer can be made by looping 6' of clear tubing with water in it half way. Measure how high the water level rises with a tape measure, multiply it by 2, convert it to LPMs

Rough conversion is1"= 27 lpm, add 3 lpm for each one inch (1/2'' of rise in the tube) of water

New engines numbers are;
63 liters per minute(2.5" water rise = 5" of water) @ 2200rpm,
76 L/Min (3.5" rise) @ 2500rpm
85 L/Min (4.5" rise) @ 2800rpm.

Worn engine that needs rebuilding are roughly double i.e.
126 L/Min(10.5"rise) @ 2200rpm
152 L/Min(14.5"rise) @ 2500rpm
170 L/Min(17"rise) @ 2800 rpm

The valves could also be out of adjustment.

Another way, same idea, is to block the blowby tube with a 1/2'' pipe nipple with a cap that has a 15/64 hole drilled in it. Use 3/8'' id looped clear tubing with water in it slipped over the oil dipstick tube. Use sharp tipped felt marker to mark the water level with the engine off, have someone start an already warmed up engine and run the rpms up to 2.2, 2.5 & 2.8k rpms. Mark each water level with the pen, measure then multiply each by 2.

This is all very simple to do, just hard to explain with words.

 

Infidel, don't you have to block off all other vents to get the proper measurement?

 

The only places it can vent are the oil dip stick and blowby unless you have a leak.
This is assuming a non Calif EGR engine.

 

might check your blow by bottle on your timing case if 12 valve is so equipped the one on my 24valve had a crack in it leaked lots of oil. little jb weld fixed her right up

jed