Cummins injector help please

Got a NT290 in a Ford truck, with top-stop injectors. On the spec tag it says to set the links at zero lash. The Cummins manual goes on to say that the screw is tightened to 5 inch pounds and that you should be able to reach down under the rocker arm and spin the link with a finger. This has never been the case, its either one or the other. Since I dont have the official torque wrench, I always went with the zero lash method and it always turns out bad ( late timing at idle, white smoke). All my other 855s have PT injectors, which are torqued in the cup, and I never have any problems with these. But the Cummins book does not specifically say that that method can be used with top-stop injectors. So... can you torque top-stops in the cup, or do I have to get that special torque wrench before it will be right? Thanks, Fritz

Fritz Maurer,

Zero lash, as you found out is not quite right.
If I recall correctly, I use to turn them, between 1/6 to 1/8 of a turn from zero lash.

No smoke at idle,

Guido.

Fritz Maurer,

It should read 1/16" to 1/8" of a turn,

Guido.

Have a look at this link about mid ways he explains the top stop injector settings, maybe it will be of some help.
https://www.youtube.com/watch?v=Oib4ZFGlmgc
I got fast talked into putting a set of injectors into a 350 that some one else had been tinkering on, it would run but no power and some white smoke of course it just started this all of a sudden, I pulled 2 injectors at random both of which had a bad spray pattern, sent the owner after new ones and he was told buy the parts man the old ones were the wrong size for that engine.?? I didn't argue that point as I just wanted to get them changed to see if what I had found was the problem. Started turning the engine to the A mark and as I watched the injector rocker go down it didn't stop as I passed the A position I backed it up tried again and had to turn it pass the A mark about 1/2" for it to stop moving, A,B&C all did the same. So I asked his employee helping me what he thought of the situation, he said turn them till they stop and torque them down to 72 inch pounds. Which I did and it fired up and ran good, next morning I went to settle up with the owner and the truck was there running he asked if if the engine sounded ok to me, to me it did I asked if they had used it yet, he said yes it's just back from delivering a load of logs to the mill no complaints, that was along time ago and with as little experience as I had at the time sometimes I still wander if that was done right.

Top stops are a pain in the drain . I have the torque wrench and set them with it . On PT's i set them at 48 inch pounds , yea i know they are suppose to be 72 inch pound or .178 on the dial indicator . . I have seen guys set the top stops wrong and knock the tip out and wash the liners down an seize the engine . I did a lot of playen with my NTC 350 small cam and made huge amounts of horse power . . Ya don't need a fancy click style torque wrench ffor the top stops as mine is a beam and works well . Set the injector then the valves . I ran a 11 and 27 valve set .