| Diesel review [message #296877] |
Mon, 07 March 2016 12:12  |
Hal StClair
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
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Senior Member |
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Just got back from a 2100 mile jaunt with the GMC so thought I'd give a little report on how the Diesel performed. We have almost 3000 miles on the conversion now. The first 1200+ miles of this trip were with the cruise control 'not home' so it may skew the numbers slightly. We had our toad with us the whole time also which does make a difference in both economy and performance of course. The last 830 miles from Quartzsite through Phoenix, up I17 to Flagstaff and then through to the Grand Canyon and on home to Albuquerque included a number of 7000'+ and a couple of 8000'+ passes. We averaged just shy of 13 mpg on this last leg with cruise working which 'seems' to be about .5 mpg better than without but sooo much nicer to drive.
Pulling the grade out of Phoenix in 95 degree weather did show an issue I have to address though. The fan clutch doesn't want to engage early enough so some slight tweaking of that will be needed. I sure wish there was an electric or air fan clutch that would work on these engines. The military H1's used a hydraulic clutch but incorporating one of those now would be a nightmare.
I think I'll also install a fan on the engine oil cooler as the temps get higher than I like at times.
Overall I was very pleased with the way it ran. I'd hopped for a little better fuel economy and maybe going with a slightly taller final gear would accomplish that but pulling a toad would probably be a 'white knuckle' affair with much less gear. 60 mph comes at about 2100 rpm now. If I come across a differential with the taller gears for REAL cheap I might be tempted but for now 14 mpg solo isn't too shabby.
Hal
(the guy that just can't leave things
"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane."
1977 Royale 101348,
1977 Royale 101586, Diesel powered,
1974 Eagle Bus 45',w/slideout,
Rio Rancho, NM
[Updated on: Mon, 07 March 2016 12:14] Report message to a moderator |
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