Diesel Bombers - HD Valve Spring Replacment

HD valve Spring Replacment

Tech Article Courtisy of PDR

On the Cummins B series motor you can change the valve springs on 2 cyl's at
a time. The thing to remember is that # 1 & 6 are a pair, # 2 & 5 are paired & # 3 &
4 are paired. You'll need a KD 2078 valve spring compressor, about $25.00 @ PDR or any
tool place that handles KD tools. A 3/8 drive torque wrench & a 1/2 drive torque wrench. 13mm,15mm,19mm, 9/16", 7/8" wrenches and sockets, .010" & .020" feeler gauges & a short flat screw driver [for setting valves afterwards]

Now clean the area around your valve covers, then remove valve covers. Use your 7/8" short socket and place it in the reverse position & attach it to the alternater nut. You'll only be able to turn the motor over backwards, but that is fine. Use the rachet to move the engine & watch your valves, you are looking for an intake valve to be on its way up [doesn't matter what cyl.] Once you've spotted the valve that's moving, lets just pretend that's it's # 2, watch it as it comes up. As it approches the top watch the exhaust valve, as soon as the exhaust valve starts to move down STOP That means that-that cyl. is on exhaust stroke [TDC] and its mate is on compression stroke.[you can check this by feeling the rockers on the other cyl. [in this case # 5] & they should both be loose] Now remove the rocker block, loosen the small bolt
first [13mm head], then the big bolt [19mm head] Use your thumb & forefinger to hold the push rods in place as you lift the rocker block off. You can now safely remove the valve springs [intake or exhaust] on that cyl. once you put that cyl. back together [the big bolt gets torqued first 120ft. lbs then the little bolt 18 ft. lbs. You can now move onto it's mates cyl & repeat the procedure. So now you've done cyls. # 2& 5, rotate the engine some more until you spot the intake valve coming up & the exhaust valve JUST STARTING TO MOVE DOWN STOP you're now ready to do that pair of cylinders. A little trick that makes things easier, when you install the new valve spring into the compressor, crank it into the tool to put some preload on the spring
before tightening the valve spring compressor, that'll make it a littler easier to get the spring on the valve. The reason for this is the KD 2078 is a short throw compressor & the new 60lb springs are a little long for it. When you do get to do # 5 & 6 cly.....the fun ones that little trick will make life much easier.