Oddities

RBBailey

NAS-ROW Addict
Callsign: KF7KFZ
I managed to get the truck over the mountains for the first time since having the diesel swap. I’m amazed at how little time I’ve spent driving this thing the way I intended when I bought it. I used to do this type of trip three or four times per year, but since owning the Defender it has been once in three years.

So this is a post-trip review. I put about 400 miles on it yesterday. It was about 70-85 degrees, and we went as high as 6500 feet, and about 80% of the drive was above 4000 feet.

The truck did well on the passes. At 4000 feet or so, while climbing the hills, I was still able to hold 50mph in fourth gear at about 2900-3000 rpm, and this kept the EGTs at about 1150-1250. I was able to hold 60mph several times, but then the EGTs would climb.

I tried something on Saturday, and this trip was the big test for the results: I put a valve in the heater core line to cut off hot water from getting into the box so that I might actually have “cool” air coming in.

So... I still cannot break through 20 mpg. No matter what I’m doing, the past three years of driving I’ve only seen 20+ three different times. I’m averaging 19.2 overall. Why? Even when I’m driving with other 110s with 300Tdi (one of them weighed 2000 lbs MORE than me!) they get 22-23, while I get low 19 range. Odd.

The valve in the heater line did not work. Even with the valve closed, and the duct set to the cool side, I’m still getting 95 degree air coming in through vents. The odd thing is that it did work for the first three hours. With outside air temps at about 70, I was getting a bit chilled just sitting in the cab with windows up! But then I stopped for an hour, after which the high temps resumed like before my modifications. The really odd thing is that it was not because the heater box eventually heated up with residual engine heat: The box itself, and the ducting, was all cool to the touch, even while I’m getting 95 degree air in the cab.

Another odd thing is that the LED daytime run lights I have in my bumper flicker when I broadcast on my ham. Oddly, only the one on the left side, which is also the side where the antenna is mounted. They do both get power from the Blue Sea fuse box. Odd.

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Red90

Well-known member
What is your boost level?

What EGTs do you get at sustained full throttle?

On the heater, is the intake ducting all fully sealed? Covering the intake vent should stop all air flow.
 
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