merrill77 wrote:There doesn't seem to be a consensus that reverting to the mechanical fan and shroud is a better solution than an effective electric fan.
Because I already have aftermarket radiator with fans & shroud, it is assured that reverting to mechanical would be a lot more work than buying a higher CFM fan that matches my existing setup. I bypassed the ammeter about a month ago - the charging system is healthy, based on my monitoring over the past month. From what I can see, the fans are already wired direct (with relays & fuses)...not through the fusebox.
So I'm going to try a fan upgrade to see where that gets me.
Good job on the Efan wiring, but if it is slowly creeping at hwy side, it can be a few things, basically the engine is generating more heat than the radiator can exchange,
1- first are you sure about your gauge accuracy
2- overadvanced timing in cruise mode
3- overly lean at cruise
4- partially opened EGR-looked at your picts, NO EGR-
1- did you check w infrared thermometer the accuracy of the gauge
2- you need to measure your timing at rpm, engine in park, brakes set, and I recommend placing the bumper against a utility pole, our rigs can be fussy and it would devastating to be run over by one's rig. use the timing gear w and wo the distributor vaccumm connected, but I believe that for EFI, the distributor advance is blocked is set by the CPU of the EFI, but at least you can measure the variations 1, 1500, 2000, 2500 and 3000 rpm
3- overly lean, you have an oxygen sensor and there is a way to monitor the output of the sensor , if you have the right sensor, voltage can be measure
4- if you have an EGR, but the EFI should compensate
of course we expect that your engine is in good mechanical conditions, a bent pushrod could create issues -from experience- lfound your original post, at 112Kmiles it should run like new, with plenty of power, it is a 401