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Topic: MPG (Read 2631 times) previous topic - next topic

Re: MPG

Reply #50 –
Always on, speed varies based on demand

Re: MPG

Reply #51 –
Early coaches had an low or high fan speed control.  Later coaches have a variable speed piloted wax capsule fan control.  Mechanical.  No electricity
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: MPG

Reply #52 –
Update.
Trip to Leavenworth Washington today. Fresh Cat 3126 engine......I saw a lot of this. Flat road, no tow vehicle, full of fuel and water. NO tail wind, NO head wind. 62 MPH. 1700  or so RPM's is the sweet spot
Up from 6 to 6.5 with sick engine.
Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: MPG

Reply #53 –
Just did a trip from Loveland CO to White Pigeon MI and back, a little over 2,220 miles total.  Was not towing anything, mostly on I-80 East and West...

To White Pigeon I averaged 9.5 miles per gallon @ 65/67mph

Back to Loveland I averaged 8.0 miles per gallon @ 62/65mph 

Configuration:
empty Black/Gray/Fresh Water tanks
very little accessories since I've not had the time to outfit my RV

v/r Bob
1986 Grand Villa
Model: 3600 ORED
Truck Maker: Oshkosh
Truck Model: V-917-2
Engine: 3208-T-250

Re: MPG

Reply #54 –
Quote from: Caflashbob –
Early coaches had an low or high fan speed control.  Later coaches have a variable speed piloted wax capsule fan control.  Mechanical.  No electricity

Mechanical cummins (like my 8.3) have the wax capsule control deal.  The newer electronic (99or 2000 on) 8.3s have a solenoid valve for high/low...as do the m11.  Ironically, a guy on the internet makes a kit to convert the electronic engines to the wax capsule control LOL.  My fans barely spin when the engine is cool.
1998 U270 34'

Re: MPG

Reply #55 –
The issue with the electronic high low is when it fails it goes to high speed.  I would convert mine to the wax capsule if it did not already have it.

I compliment Gracerace for the 63 mph. I tow at 70 and hit the hills floored. Average for the last 12k Miles is 8.1 mpg
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: MPG

Reply #56 –
Quote from: krush –
Mechanical cummins (like my 8.3) have the wax capsule control deal.
What does the "wax capsule" on your coach look like?  I'd really like to see a photo of it.

AFAICT, our '93 does not have any kind of 2-speed device.  I have looked closely at each of the hydraulic hoses between the hydraulic pump and the fan motors.  I can't see anything that looks like a speed controller.  I think on our coach, the fan speed is controlled by the hydraulic pump speed, which is determined by the engine speed.  Higher engine RPM = higher fan speed.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: MPG

Reply #57 –
Quote from: Bob Fryer –
Just did a trip from Loveland CO to White Pigeon MI and back, a little over 2,220 miles total.  Was not towing anything, mostly on I-80 East and West...

To White Pigeon I averaged 9.5 miles per gallon @ 65/67mph

Back to Loveland I averaged 8.0 miles per gallon @ 62/65mph 

Configuration:
empty Black/Gray/Fresh Water tanks
very little accessories since I've not had the time to outfit my RV

v/r Bob
You should be getting better milage than that. Do you have the roof storage pod? Any black smoke? Engine temps low? My cat runs 10.8 to 11.1 at 65 to 68.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: MPG

Reply #58 –
The difference between the 250 hp and 300 hp makes the 250 work harder. I had the same issue on one of my cranes 53,000 lbs. 350 hp 7mpg, my last one 31,000 lbs 210 hp 5.2 mpg.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: MPG

Reply #59 –
Quote from: Bob Fryer –
Just did a trip from Loveland CO to White Pigeon MI and back, a little over 2,220 miles total.  Was not towing anything, mostly on I-80 East and West...
To White Pigeon I averaged 9.5 miles per gallon @ 65/67mph
Back to Loveland I averaged 8.0 miles per gallon @ 62/65mph 
v/r Bob
Could be headwinds, tire pressure, alignment, air cleaner or a combination of these. With a narrow body and light load, it should be at least one mpg better. Sometimes headwinds seem to follow you around. They make a huge difference.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: MPG

Reply #60 –
Or the rings are not seated totally.  My m11 was mentioned on the trucker pages to not seal up until 150k miles.

The lower back pressure resonator I think added some final ring break in.  No way to verify other than seat of the pants dyno.

Drive it like you stole it.  Maybe a chassis dyno run? 

Fuel system might need attention.  Translation:  turn it up. 

How's your fuel lines?  Cracked lost power and mpg
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: MPG

Reply #61 –
Quote from: Chuck & Jeannie –
What does the "wax capsule" on your coach look like?  I'd really like to see a photo of it.

AFAICT, our '93 does not have any kind of 2-speed device.  I have looked closely at each of the hydraulic hoses between the hydraulic pump and the fan motors.  I can't see anything that looks like a speed controller.  I think on our coach, the fan speed is controlled by the hydraulic pump speed, which is determined by the engine speed.  Higher engine RPM = higher fan speed.
2000 U320 mid entry  #5688
2006 Jeep Liberty


USMCR retired
SDFD retired
FEMA US&R TF8