Bus Conversions dot Com Bulletin Board
October 31, 2014, 01:06:27 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: 500 Members as of May 5th, 2006.  Smiley  3,499 Members as of October 21, 2012 Cheesy

   Home   Help Forum Rules Search Calendar Login Register BCM Home Page Contact BCM  
Pages: 1 2 [3] 4   Go Down
  Print  
Author Topic: 64 Prevost, NEED (not want) custom cooling!  (Read 4591 times)
zubzub
Hero Member
*****
Offline Offline

Posts: 1164


'53 4104. Roadworthy but rough around the edges.


WWW

Ignore
« Reply #30 on: June 03, 2010, 03:17:23 AM »

Consider a pulley setup if it is possible.  look at a later prevost where a pulley and belt drive a shaft to a miter box that turns a fan.  If you get a thermo fan clutch on the Fan you save horses big time and if you can source some scrap for the miter box this is a simple reliable system....less fancy bet gets it done...remember KIS there are lot's of other things to work on on your bus....(I'm guessing?)   here are a couple of pics  a  of a mid 70's prevost miter box



« Last Edit: June 03, 2010, 03:21:29 AM by zubzub » Logged

RoyJ
Full Member
***
Offline Offline

Posts: 178





Ignore
« Reply #31 on: June 03, 2010, 02:59:55 PM »

That does look a bit like my engine bay. The problem is, I don't have that "outer part" on the bottom main pulley. It ends where the multi-vbelt part stops, and then it's the back bumper. I also have this vertical bar that would get in the way.

This makes no sense at all, how could the factory have fitted any mechanical fan to such a setup? If hydraulic, where was the pump driven off of? I'm guessing the engine may have been swapped in. If I use a hydraulic setup, I'd have to put the pump where that alternator is in that pic.

I'll get some pics posted up soon. Does anyone know if this board has a photo uploading section?
Logged
Just Dallas
Bus Conversion Stuff on a Budget
Hero Member
*****
Offline Offline

Posts: 842



WWW

Ignore
« Reply #32 on: June 03, 2010, 03:03:21 PM »

Removed
« Last Edit: July 14, 2010, 07:10:19 PM by Now Just Dallas » Logged

I'm just an old chunk of coal... but I'm gonna be a diamond someday.
Tim Strommen
Electronics Geek
Sr. Member
****
Offline Offline

Posts: 303



WWW

Ignore
« Reply #33 on: June 03, 2010, 03:29:32 PM »

On my Gillig the PS and fan-drive (and the wheelchair-lift I took out) are from the same pump, in a single loop configuration.

You can do a hydraulic drive from the accessory ports on your block - from my memory there are two (one at the end of each cam shaft). You need a pump and a motor (or two pump/motors), a reservoir, pressure relief valve right after the pump (bypassing to the reservoir - some pumps come with this built-in), and a control valve at the absolute minimum.

You can do an el-cheepo 2-speed control by getting a solenoid valve that has a restrictor fitting in it. For best safety, you should set it up so that the fan will get max-flow with the pump spinning and no power to the solenoid (bypass closed), and let restricted fluid bypass the fan motor only when the solenoid is powered (bypass open) - this way if the solenoid fails or the circuit supplying it fails, the fan will at least be able to cool the engine completely, you'll just have more "hunting" with the thermostats (relatively fail-safe design).

You can fancy it up with a variable-flow control valve to change the speed of the motor using the same principal - they make electronic ones if you are good with that stuff, you can whip up a control circuit that uses the return temperature of the coolant to the block as a speed control stimulus (not the kind we pay for later with taxes).

Any hydraulic shop should have the parts to do this.

-Tim
« Last Edit: June 03, 2010, 03:32:04 PM by Tim Strommen » Logged

Fremont, CA
1984 Gillig Phantom 40/102
DD 6V92TA (MUI, 275HP) - Allison HT740
Conversion Progress: 10% (9-years invested, 30 to go Smiley)
RoyJ
Full Member
***
Offline Offline

Posts: 178





Ignore
« Reply #34 on: June 03, 2010, 06:34:26 PM »

The bus has no power steering, so the hydraulic loop would have to be totally new.

I think for a $10k bus, doing a brand new, custom hydraulic loop would be a little cost prohibitive for me at this point. If I go hydraulic, I'd have to wait for a good salvage unit to show up. The engine does have lots of leftover pullies, so I'm sure I'll find a place for the pump.

I did a little maintenance on my band-aid solution to make sure the bus can atleast get around safely. Took apart all the fans and motors, cleaned out the dirty bearings/bushings with solvent, and lubed with fresh grease / machine oil. Also sanded and repainted the shroud, and put in new double foam seals. To my surprise, the fans pull much harder than before. Don't know how many amps they pull, but the 6 gauge wire was warm at the terminals. The wind generated would pull the rad access door shut from 6" away.

By no means am I giving up in finding a new solution, but it does show the PO put in a some effort to design it as well as he could. They're certainly better than those flex-a-lite stuff.
Logged
zubzub
Hero Member
*****
Offline Offline

Posts: 1164


'53 4104. Roadworthy but rough around the edges.


WWW

Ignore
« Reply #35 on: June 03, 2010, 09:19:15 PM »

here is a thought.  If this bus has worked the way it's set up and has pulled grades etc...has an operating engine temp gauge that you can watch from the cock pit....why change it?  I know everyone says it can't be done but apparently the PO did it.  And it has worked for 20 years, so why change it? 
Logged

RoyJ
Full Member
***
Offline Offline

Posts: 178





Ignore
« Reply #36 on: June 03, 2010, 10:15:51 PM »

here is a thought.  If this bus has worked the way it's set up and has pulled grades etc...has an operating engine temp gauge that you can watch from the cock pit....why change it?  I know everyone says it can't be done but apparently the PO did it.  And it has worked for 20 years, so why change it? 

My origional reason is the radiator's need of replacement, and I have to decide whether or not to stay the same size. If I upsize the radiator (which I realized I can't, no space), then I'd have to get a new fan setup anyway, so might as well start planning for a proper replacement.

So far, I don't have any personal experience driving the bus yet, so I have no idea how well the setup works. I can only relate to what the PO told me (and he admits to relying on the mister on hot days). I'll make sure to do a lot of hot weather hill climb test before the maiden trip.
Logged
zubzub
Hero Member
*****
Offline Offline

Posts: 1164


'53 4104. Roadworthy but rough around the edges.


WWW

Ignore
« Reply #37 on: June 03, 2010, 10:34:40 PM »

Forgot to mention earlier, with a miter box you wouldn't need the extra pulley just run a serpentine belt.  Re the mister s et al, the naysayers will say, look it ruined the rad etc...but the yea sayers will say how much are you really going to use this, and it's not like the rads are going to rot right away.  If you find a transit scrap yard they have some nice smaller rads, and the cool thing about transits is that they are maintained while in service so a retired scrapper can have some nice new rads etc on it.
Logged

DMoedave
Sr. Member
****
Offline Offline

Posts: 322





Ignore
« Reply #38 on: June 04, 2010, 03:45:49 AM »

We have a 6V71 with hyd fan drive off a Carpenter/Thomas transit 6v. It was/is a Webster unit. webster harder to get parts now but we replaced the drive motor with a webster copy. Robert said the hardest part of the repower was the cooling system! Nimco in NJ will have take outs and as Zub says get to a transit yard for ideas. Wonder what the stock engine was in your rig if they repowered with a 6V? Ours originally had a 4-71. good luck
Logged

we love our buses!!! NE Pa or LI NY, or somewhere in between!
TomC
Hero Member
*****
Offline Offline

Posts: 6869





Ignore
« Reply #39 on: June 04, 2010, 07:13:56 AM »

Electric fans for radiators have been discussed extensively.  If they are so good, don't you think OEM's would have been using them since they are easier to set up then a direct drive or a hydraulic drive and they take less horsepower drag?  On big rigs, they had a setup that had 6-8 fans (depending on the radiator shape) and didn't work on a front radiator!  Trying to get an electric motor that will pull like a 32" 8 bladed fan (the equivalent of 30hp) just won't happen.  30hp with a 24v electric motor would have to draw about 950 amps! With our side intake radiators, the only way to go is with either a direct drive or hydraulic motor setup.  We've had too many members try electric and by now have realized that using an electric motor for the radiator is like banging your head against the wall because it feels so good. Good Luck, TomC
Logged

Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.
kyle4501
Hero Member
*****
Offline Offline

Posts: 3145


PD4501 South Carolina




Ignore
« Reply #40 on: June 04, 2010, 07:52:28 AM »

here is a thought.  If this bus has worked the way it's set up and has pulled grades etc...has an operating engine temp gauge that you can watch from the cock pit....why change it?  I know everyone says it can't be done but apparently the PO did it.  And it has worked for 20 years, so why change it? 
That's just it, it didn't work - hence the need for misters. How many commercial vehicles come with a mister system? Misters are a great bandaid to temporarily increase the cooling system capacity, but, misters are not a permanent solution.

The engine isn't always the limiting factor in HP available to move your bus - heat rejection abilities of the radiator can limit things too.

A properly sized radiator won't care what moves the air, as long as it gets enough air moving across it. The smaller the radiator, the more air required = more fan HP.
Sure electric motors can do it & use the batteries to buffer the peak power required from the main engine - BUT - the electric fan will HAVE TO move the required air to keep the temps in line during peak demand. That means the elec motor MUST be capable of that level of horsepower (which is in excess of 20 HP).

SO, for the time being, "Run what 'ya brung" & see how it is. Your useage may be puttering around flat, cool areas & your system will work just fine as is. OR, you may find you need to cover distances quickly (due to limited vacation time) & the hills must be climbed (which creates more heat to be rejected) which mandates more cooling.

Only you can determine what your real needs are.

 
Logged

I know you believe you understand what you think I said, but I am not sure you realize that what you heard is not what I meant. (R.M. Nixon)
luvrbus
Hero Member
*****
Offline Offline

Posts: 12802




Ignore
« Reply #41 on: June 04, 2010, 08:03:21 AM »

I know Mark  (Boomer) is reading this and having a good laugh he is all over Mexico , Northwest and the Southwest using his electric fan setup on a 45 ft 102 wide Eagle never once have I heard of overheating on his bus 


good luck
Logged

Life is short drink the good wine first
kyle4501
Hero Member
*****
Offline Offline

Posts: 3145


PD4501 South Carolina




Ignore
« Reply #42 on: June 04, 2010, 08:34:56 AM »

Yeah, but he isn't using low hp elec fans either, is he?

Not all electric fans are equal. The fans he used are not anything like the typical automotive radiator fans.

Another thing, If I recall, he spent a bit of time developing the total system. Quite a bit of work in the fan shrouds too.
« Last Edit: June 04, 2010, 08:42:37 AM by kyle4501 » Logged

I know you believe you understand what you think I said, but I am not sure you realize that what you heard is not what I meant. (R.M. Nixon)
luvrbus
Hero Member
*****
Offline Offline

Posts: 12802




Ignore
« Reply #43 on: June 04, 2010, 09:00:53 AM »

Yep he did do it right Kyle but some of these guys say it won't work period with electric fans that is point I am trying to get across it will work if done right



good luck
Logged

Life is short drink the good wine first
kyle4501
Hero Member
*****
Offline Offline

Posts: 3145


PD4501 South Carolina




Ignore
« Reply #44 on: June 04, 2010, 11:31:33 AM »

Clifford,
Good to see at least we're still on the same page.  Grin
Logged

I know you believe you understand what you think I said, but I am not sure you realize that what you heard is not what I meant. (R.M. Nixon)
Pages: 1 2 [3] 4   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!