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Topic: Engine fan delete?  (Read 6523 times) previous topic - next topic

Re: Engine fan delete?

Reply #125 –
Quote from: craneman –
I had a '63 Flexible that I was going to convert to a motorhome. I bought it in Portland Ore. It used ford starter motors for the heater blowers and had an oil cooled alternator. Sold it when I found the '81 FT.
Probably an 8V-71 with a 300 amp direct drive, brushless, oil cooled alternator. They were pretty standard on all buses. My ex-Greyhound had one. Big, heavy and probably expensive but trouble free.

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

Re: Engine fan delete?

Reply #126 –
Update: ran this past weekend  to the Sebring races with the small  single car 3200#  trailer  and the engine door modified  .  Towed fine and the temp sits on 195 F with the ambient near 96f .    Open the engine door and temp drops to 190 or less..  Run at 2100 RPM and the temp is stable,  but run up to 2300 and temp rises to 200.  So, clearly not a lot of reserve  cooling .  I need  to reseal the fan shroud a little  and maybe move the sensors around . But  all of the 6 fans come on when hot and they cool the engine quickly when off power.
    Faster, quieter, and for some reason less oil consumption and black smoke under load.    This may be due to better burn at a little hotter chamber temps..  No idea why the oil consumption would drop .  Was about 2 qts per 1000 miles and now maybe 1 .
 Fuel MPG is a solid 10 .7 or more.  Pretty sure it will be 11 if I dont pull something .
  I wil carry the OE fan for any runs up north thru the mountains.    For the flats of Florida  we are good.  80 % success at this point  .  My new to me 440 watt panels should be in  in a week or so so that the AC and engine fans can all run  off the solar batt pack .

Re: Engine fan delete?

Reply #127 –
New door mod from wife's input .
I don't hate it.
Ran down the road with steamers on the back end. Video will be up in a couple of days.
No surprises tho. Linear flow along the side . Pretty dead air behind .

  My  Sim says that there is a high probability that the airflow without any fans, may be into the engine door at medium speed. Not out.

Re: Engine fan delete?

Reply #128 –
Ask NASCAR drivers, that area sucks. Semi's started putting a bubble on the backs of trailers to get better mileage.
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: Engine fan delete?

Reply #130 –
Mike was that with the fans on?
1999 36 ft U270
Build 5465

Re: Engine fan delete?

Reply #131 –
No.
It's really hard to get it hot .  I have the shrouding nice and tight and the fans only run a couple of minutes to cool off .
  I will have to run it for about an hr at 2300 rpm to get the fans on solid.
I thought that they would come on but I was wrong.
  The airflow flows into the rear door at this point . 
There's a fair chance that the fans could blow into the rear door and with a deflector on the side door, the airflow would be consistent and flow into the rear and out the side .
  I think that I can turn my fans around pretty easily. May try it next pass .

Re: Engine fan delete?

Reply #132 –
I had a van that had the rear windows that opened at the bottom.  One time I left them open thinking I'd get some ventilation from the front through to the rear and out.  Didn't happen.  The air would enter at the rear and I would smell gas fumes from the exhaust.   
Freightliner MT55 w 24 ft box
All aluminum.

Re: Engine fan delete?

Reply #133 –
Right
It's working well as is now. I may try to reverse the fans while adding a small deflection panel on the side vent. If I have problems.  I agree , the natural flow is into the rear panel and out the bottom and sides.

Just returned from another 300 mile trip to Sebring running at 200 most of the way. Runs great less black puff on take off and fast.
Now for the annual wedge brake adjustment
And prep for paint

Re: Engine fan delete?

Reply #134 –
During your video what speed were you at? Looks like 35-40. Would be curious what it does at higher speeds
Scott

Re: Engine fan delete?

Reply #136 –
Latest tid bits.  My fans are powered by the solar system and the added 100 Amp delco one wire alternator .  Turns out that the fans must draw about 110 amp at full cool.    Oh yeah. solar works less good at night :)      Ran about 1000 miles over the weekend to Road Atlanta for a race(didnt win)  and averaged a tiny bit over 10mpg . But the return trip was overnight and I had to use the boost  to combine the alternators to power the fans .
  The  removed fan drew a lot of power( 30-50HP?)  and that power has to be replaced by something. It takes a lot of amps .    I will read my amp draw next chance that I get .
  This also explains why my AC and the fans dont make the solar system happy . Fans at 80 ish  amp, AC at 70 amps.
 Still the compromises  to remove the BA fan are worth it to me . 15-20 % better fuel burn( 80-100$ per 1000miles?) , more power, much quieter, less oil consumption  at higher temps. ??  No idea why other than burning off moisture .   
   

Re: Engine fan delete?

Reply #137 –
https://scontent.ftpa1-2.fna.fbcdn.net/v/t39.30808-6/335482602_937946637343869_8711101979077769158_n.jpg?_nc_cat=111&ccb=1-7&_nc_sid=5cd70e&_nc_ohc=fVuXl-D_Q-4AX8edUN6&_nc_oc=AQmVq9LYH6jmXw5rGq7DPHkiRqKC0iFfUgI_7r7n3XHa1yAaJyvHXBy76mGC9LE-ebo&_nc_ht=scontent.ftpa1-2.fna&oh=00_AfAzBLgpFcKSz-wkMTxWTLVCyDoAvkXpYRr0yd0jvvnBmg&oe=641B865F
  We talked about air entering the rear door.  This bus shoves the air in.

Re: Engine fan delete?

Reply #138 –
What a great looking coach! Buick, Hall-Scott or Cummins diesel?

At the start, our FD was mostly 590 and 935 Hall-Scott. Good engine.

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

Re: Engine fan delete?

Reply #139 –
One of those with the straight 8 was on our early motorhome searches. I wound up buying a commuter Flexible with the V-671 in Portland but never finished the conversion before finding our '81 40' FTX sold it to my  cousin and he drove it to Anchorage. 
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: Engine fan delete?

Reply #140 –
Quote from: Protech Racing –
  We talked about air entering the rear door. 
Really makes me curious on what's is actually happening in regards to air pressure and flow direction zones. Im assuming there is a hi pressure zone ahead of the coach and a low pressure behind. Low pressure would assist in pulling air out of the back of the coach at freeway speeds. But you can guess all day long. Proof is in the wind tunnel.

Re: Engine fan delete?

Reply #142 –
Anyone seen the Ford vs Ferrari movie?  How about that tape and yarn trick?  With a rear camera, you may be able to see what it does while on the move.  Worst case, a Go Pro with a suction cup mount.
Keith
2003 U320 38' #6197

Re: Engine fan delete?

Reply #143 –
Mike had that prior at I think was 50-60 mph.

Re: Engine fan delete?

Reply #144 –
Quote from: dsd –
Mike had that prior at I think was 50-60 mph.
Very little flow in any direction at the rear opening at 55.  Kinda dead area.   
          Maybe a roof deflector would gain a little flow . I see most modern DP has some sort of air control at the roof edge. 

Re: Engine fan delete?

Reply #145 –
Quote from: Protech Racing –
Very little flow in any direction at the rear opening at 55.  Kinda dead area.   
          Maybe a roof deflector would gain a little flow . I see most modern DP has some sort of air control at the roof edge. 
I was thinking they were after filling the void behind the coach, IE low pressure area. This would make me guess that the sides/top near the rear are also a low pressure area but higher than the rear. Think about a big hole punched in the normal air pressure, getting pushed/sucked back in. I think the manometers would show a differential between the sides and the rear. If you can use this to naturally draw air across radiator you  would be using the energy already spent in propelling the coach forward. Free cooling, or I should say prepaid cooling being a byproduct of forward movement . Could be a simple solution. Everyone has seen the big flaps behind a 18 wheeler trailer. Same idea I think 🤔 Fun stuff to think about
Scott

Re: Engine fan delete?

Reply #146 –
Latest. The fans work well.
Some glitches with the controllers, that don't seem to be weather resistant  . I carry a spare and may change to a weather tite controller.
My connections on the gm fan pack face upwards and have held water enough to corrode the connection.  Drilled a small drain hole  .
 I still carry the oe fan for karma .
Fuel burn is a solid 1-2 mpg better.

Re: Engine fan delete?

Reply #147 –

Well I wanted to add my two cents. The Bronco engine swap was overheating. FFR 16" dual fans 3000 CFM each. Very well shrouded. 110 OAT. Would overheat while driving either slow or freeway speeds. Yes it's hot out and so was I. No air conditioning. FFR Amperage draw at 28 amps total. Air exit speed from radiator about 8.8 MPH. FFR support was helpful but without a resolution. Radiator is 3.5 inches thick with a 1" condenser in front of it and a pair of oil coolers. Engine and trans. Replaced FFR fans with SPAL 16 inch fans from Summit racing. 188$ each. Next day delivery. 2/3 the CFM rating. Exit air speed increased to 20mph. No longer overheats and temp cycles between 195 and 205 with fans cycling. Will be installing a two speed set up that runs both fans in series for low and parallel for high speed. Hopefully I'll be able to run the AC with this set up. Total amperage draw is 56 amps on high. 56 amp is about 1 HP. Wish I could have installed a direct drive but no room. Being able to cool with 1HP is great IMO but it's a big draw. Add in HVAC components and headlights with windshield wipers and its  big amperage numbers to support.
Amazon.com: Spal 30102082 16" Paddle Blade Puller Fan : Automotive

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Engine fan delete?

Reply #148 –
Good to know. 
Thanks