3406B hopping/starving for fuel

There is a #5 o ring boss plug on the filter base. Check your pressure there. 42 at idle should never go below 30-32 though they usually won’t miss till below 20.

just a thought since it’s done it from overhaul and pump was done at overhaul if I’m remembering correctly, check the bonnet nuts on top of pump. I almost bet you have one loose. They can be loose and not leak. 1/2 drive torque wrench to 110ftlbs will tell the tale. If you have the spline socket

 

Actually the torque spec on the hold down bushings when working with used barrel and plunger with either used or new bonnets is 200-220ftlbs as apposed to 180 on all new barrel and plunger...back mark the bushing relative to the pump body, back of a tiny bit, torque to 200, back off a touch, then take it down to 220. then just for refrence check your marks to see how much you went. The back off and stuff is to prevent false breakaway torque you'll get if you try just going down from where they have been since last guy had it apart. I reccomend getting a systems testing and adjusting manual for any b or c model and reading it cover to cover and buy the splined tool for the holdown bushings, get 6 new updated bonnets #108-2104 (make sure and verify the #) get 6 nea orings, get a tube of valve lapping abrasive compound and a piece of hard machined 1/4" or thicker steel plate or w thick piece of glass and remove barrels and plungers and lap them all. With the new bonnets vergine sealing sorfaces and the freshly lapped faces with the 200-220 spec it will amaze you kow smooth it will run, also reccomend checking timing atleast statically and make sure all weights, eclips, thrust washers,nmake sure e clip grove in spool is not worn. Etc. Then if this all looks good removev

 

210 is what I intended to say I guess I fat fingered that. Still no excuse for not catching it

 

Could also be injector nozzle pop off chatter...that can be inconsistent.

 

Hopefully @PSM379 will update us when he figures it out.

 

Did you figure it out?