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Topic: 8.3 and 34' Performance (Read 1746 times) previous topic - next topic

Re: 8.3 and 34' Performance

Reply #25
Bob,

With your fan "idle"  until coolant reaches 185 degrees F, what are your INTAKE MANIFOLD temperatures.  No air flow could cause an issue there.

Totally agree a 199 to full fan speed is perfect.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: 8.3 and 34' Performance

Reply #26
In a SOB tried setting my hyd fan to only come on at 175 at low and 190 on high. Found manifold intake temps where running 50 f over ambient if water temp was below 175. So set it so fan is at low, all the time, until it reaches 190.
Believe Cummins recommends a max of 30 f over ambient for intake manifold air temps.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: 8.3 and 34' Performance

Reply #27
Jim,

Sounds perfect.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: 8.3 and 34' Performance

Reply #28
Brett the intake manifold is and was 20 or so degrees over ambient with either controller.

I bought my 199 max speed controller from a Beaver guy with two of them. 

As far as I know the entire industry runs the 199 unit. 

Foretravel probably got sick just like I did with customer calls "why does my temp gauge move. My car does not.  Why is this overheating?"

Probably why the early u280's with the cat had overcooling problems.  Motor barely warmed up.

Foretravel partially blocked the rear radiator.

So when they went hydraulic side drive they intentionally put the system on high speed if warm.

Less phone calls. 

The power loss is not as noticeable unless you drive through the Rockies
"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: 8.3 and 34' Performance

Reply #29
Brett the intake manifold is and was 20 or so degrees over ambient with either controller.

I bought my 199 max speed controller from a Beaver guy with two of them. 

As far as I know the entire industry runs the 199 unit. 

Foretravel probably got sick just like I did with customer calls "why does my temp gauge move. My car does not.  Why is this overheating?"

Probably why the early u280's with the cat had overcooling problems.  Motor barely warmed up.

Foretravel partially blocked the rear radiator.

So when they went hydraulic side drive they intentionally put the system on high speed if warm.

Less phone calls. 

The power loss is not as noticeable unless you drive through the Rockies

So without the fan running and  foot to the floor, your intake manifold temp is only 20 degrees over ambient?  Not sure how.
How hot is the air coming out of the turbos?
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: 8.3 and 34' Performance

Reply #30
The fan ALWAYS runs.  No off.  Idle speed on startup.  Fan starts to ramp up at 185.  VPMS reports 178 at its sender.  Thermostat is partially closed and fan on low.  Intake manifold is still roughly 20 degrees over ambient as far as I have noticed.

Running VPMS before the controller change I would get 2 mpg increases on the RMPG on flat ground. Cool conditions.

Ah the fan finally went to idle speed.

I eliminated all other draws first.

Has not done that since I and Bob Rosen both changed our controllers.

.5  mpg increase or more.  Way better low rpm pulling power versus downshifting.

Thankful for the VPMS's help in showing what was going on if one cared to look and wonder why....
"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: 8.3 and 34' Performance

Reply #31
The fan ALWAYS runs.  No off.  Idle speed on startup.  Fan starts to ramp up at 185.  VPMS reports 178 at its sender.  Thermostat is partially closed and fan on low.  Intake manifold is still roughly 20 degrees over ambient as far as I have noticed.

Running VPMS before the controller change I would get 2 mpg increases on the RMPG on flat ground. Cool conditions.

Ah the fan finally went to idle speed.

I eliminated all other draws first.

Has not done that since I and Bob Rosen both changed our controllers.

.5  mpg increase or more.  Way better low rpm pulling power versus downshifting.

Thankful for the VPMS's help in showing what was going on if one cared to look and wonder why....

Now I understand, when you said idle, assumed, not running, but in actuality, running at low speed all the time till 185 f. is reached.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: 8.3 and 34' Performance

Reply #32
Bob, et al;

I misunderstood as well.

Totally agree with LOW fan until 1999 degrees F, then full high.  Variable slightly preferred over low all the way until it calls for high.  Said another way, starting to ramp up fan speed with it is a few degrees over thermostat control would be great.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: 8.3 and 34' Performance

Reply #33
I think the mechanical control is variable, by the nature of the system design. I haven't verified this.

The electronic control on m11 and electronic engines seems to be High/Low with a solenoid control.
1998 U270 34'

Re: 8.3 and 34' Performance

Reply #34
The piloted wax capsule fan speed controllers speed increase is a straight line starting at 15 degrees below it max speed temp rating.

Like I have posted here many times and bob rozen tested also we both saw improved power, better mpg and zero temp differences. 

Win, win.  The resonator and the low rolling resistance Michelin tires and a blue tec Donaldson air filter and having the cam position sensor replaced and good batteries and alternator and a medium solar system to turn off the alternator going down the road made an impressive difference in the engines ability to pull grades.

All the unicoaches have the same basic cooling fan system.

Not sure what temp controller is on a 8.3 but the number is on the controller which is on the pipe at the rear of the coach and has two lines running into it.  I assume it's the same 180 unit.

Massive power loss.  Heats up the engine oil excessively which can damage the fan motors and the steering box running hot all the time.

Someone needs to put temp tell tales on the fluid reservoir to see the max hot it gets? 
"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: 8.3 and 34' Performance

Reply #36
Looks like the dynamatic unit,  the adjustable part  is unknown 
"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: 8.3 and 34' Performance

Reply #37
Here is a i think a source for the 199 degrees controller

Source Engineering Inc | Custom RV Chassis | Eugene, OR

Verify the 199 degree full speed
"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: 8.3 and 34' Performance

Reply #38
The piloted wax capsule fan speed controllers speed increase is a straight line starting at 15 degrees below it max speed temp rating.

Like I have posted here many times and bob rozen tested also we both saw improved power, better mpg and zero temp differences. 

Win, win.  The resonator and the low rolling resistance Michelin tires and a blue tec Donaldson air filter and having the cam position sensor replaced and good batteries and alternator and a medium solar system to turn off the alternator going down the road made an impressive difference in the engines ability to pull grades.

All the unicoaches have the same basic cooling fan system.

Not sure what temp controller is on a 8.3 but the number is on the controller which is on the pipe at the rear of the coach and has two lines running into it.  I assume it's the same 180 unit.

Massive power loss.  Heats up the engine oil excessively which can damage the fan motors and the steering box running hot all the time.

Someone needs to put temp tell tales on the fluid reservoir to see the max hot it gets? 
Bob, understand the power loss because of hyd pump supplying power to the fans running more than necessary, but how does it heat up engine oil excessively which can damage fan motors and steering box? One would think that if your fan ran too much, engine oil would be cooler [discounting thermostats]?
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: 8.3 and 34' Performance

Reply #39
That much hp through the fan does  seems to not allow  the oil to cool?.  Radiator is in front of it.  180 degrees.

Only way to know is to put a heat changing plaque on the reservoir I would think. Records the highest temps. 

The shop foreman said continuous full speed would heat the systems oil

Reservoir is next to the motor and trans.  Opposite side from the radiators
"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: 8.3 and 34' Performance

Reply #40
So where is the engine oil cooler and what cools it? And how does heating up engine oil heat up and damage steering box and fan motors?
"Massive power loss.  Heats up the engine oil excessively which can damage the fan motors and the steering box running hot all the time."
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: 8.3 and 34' Performance

Reply #41
Bob,  could you share the part number that is on the wax capsule?  I've already bought one  wrong one....but may have a source if I have the correct part number. 

It sounds like you've got this thing figured out and going your way. 
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: 8.3 and 34' Performance

Reply #42
I believe all the valves are adjustable ... their is a flat cap with an allen head.. remove it and their is another allen head below that.. turn it in or out to adjust... The part numbers on them are for setting of the allen head I believe.. (IIRC)

Re: 8.3 and 34' Performance

Reply #43
I believe all the valves are adjustable ... their is a flat cap with an allen head.. remove it and their is another allen head below that.. turn it in or out to adjust... The part numbers on them are for setting of the allen head I believe.. (IIRC)

If that's the case, is our OEM valve also adjustable?

Re: 8.3 and 34' Performance

Reply #44
If that's the case, is our OEM valve also adjustable?
Look at the top of the valve.. if you have a flat looking washer with the allen head.. open it up. if you see another allen head inside or even if you dont, stick the allen inside the valve and see if it  seats into another allen screw... see if it turns. If it does then it will adjust.. DO NOT TRY THIS WITH THE ENGINE RUNNING!! IT WILL SHOOT OIL EVERYWHERE!!

DO TRY THIS WITH THE ENGINE ON!!! DO NOT!!!

Contents are under pressure when the engine is running.

Re: 8.3 and 34' Performance

Reply #45

Not sure what temp controller is on a 8.3 but the number is on the controller which is on the pipe at the rear of the coach and has two lines running into it.  I assume it's the same 180 unit.

My temperature gauge on the dash stays right around 180degrees in almost all conditions (except climbing massive hills, in which it creeps up 5 degrees). This is proper and as designed.  Even after a long run, if I walk to the back of the RV after parking and have engine rev'd up, the radiator fans are not running fast.  I feel the system is working correctly.  The target engine temp is 180-190.
1998 U270 34'

Re: 8.3 and 34' Performance

Reply #46
It's not the temp,  both controllers show the same temps.  It's the power increase, less system heating up and better mpg.

Not sure what you have on your coach? 

How do you know it running at low under a load in warm weather?

At idle some may well be on the idle speed.

My VPMS would occasionally show a 2 mpg jump in rmpg which showed the fan speed finally went to idle for a few miles.

2 mpg is quite a lot of power consumed.  Matches the power consumption quotes from source engineering and Brett here.

No off normally.  Just low speed then ramp up to high
"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: 8.3 and 34' Performance

Reply #47
Look at the top of the valve.. if you have a flat looking washer with the allen head.. open it up. if you see another allen head inside or even if you dont, stick the allen inside the valve and see if it  seats into another allen screw... see if it turns. If it does then it will adjust.. DO NOT TRY THIS WITH THE ENGINE RUNNING!! IT WILL SHOOT OIL EVERYWHERE!!

DO TRY THIS WITH THE ENGINE ON!!! DO NOT!!!

Contents are under pressure when the engine is running.
Clockwise or counter clockwise to raise the set point? Any idea how many turns to raise it ~15 degrees?

Re: 8.3 and 34' Performance

Reply #48
Where do you have axle ratio changed?  From what gearing to what gearing?  How much cost?

Larry