Author Topic: MCI 7 extra radiators  (Read 10657 times)

Offline Buffalo SpaceShip

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Re: MCI 7 extra radiators
« Reply #15 on: August 06, 2006, 08:32:39 AM »
You already have a third radiator if you have not removed you bus heat. I use my large bus heat radiator for extra cooling. In the summer I can turn the heater on and I made it so I can exzaust the bus heat to the out side. In the winter I return the heat to the inside. 

I too have used the coach heat on occasion to take some heat off of the engine. But how did you route the heat away from the interior for summertime use?

Brian Brown
4108-216 w/ V730
Longmont, CO

Offline ceieio

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Re: MCI 7 extra radiators
« Reply #16 on: August 06, 2006, 12:33:00 PM »
    That looks like the transmission cooler I installed in our MC-8 (same location). We re-routed the transmission cooler hoses so the transmission fluid goes to the this cooler first, through the OEM cooler, and then returns to the transmission. Since doing this, all temperatures (water, oil, and transmission fluid) run about 10-15 degrees cooler. And that is without turning on the fan. We have not been in any mountains yet see give it a real test.
    Do you pull outside air in, or push inside air out with the fan?  Jack

Jack - It pulls outside air into the engine bay.  I get to test it all the time as I have a first gear pull to get to my house :)  (I can take it at second if I make more of a run at it).  At slow speeds it seems to work OK too. Pulling the hill out of Las Vegas in mild temps (80's) it really helped too.

I wonder about exhusting the air (rather the little fan working against air pressure to draw in and exhaust air) when the load is high.    Pulling the hills in Northern California and Southern Oregon it helps as well.  These are steep and long, with my bus in 2nd gear most of the time, RPM's up so lots of air coming through the blowers.  I can still see an impact on the dash gage when I switch on the fan under these conditions, so it must work OK.  When I get current projects done, I will start thinking about better ducting to see if I can get more benefit.

I think I would like to come up with some louvers or vents that can be opened or closed near the top of the engine doors to exhaust the blower heat directly out of the back of the bus without passing it through the engine bay.  Seems like it would help in hot weather.  I would like to be able to close these in cooler weather to keep the temps in the warmer range.  Not sure if it will have any effect if I do it.  Opinions anyone?

Craig - MC7 Oregon
Craig MC7 - Oregon USA


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Re: MCI 7 extra radiators
« Reply #17 on: August 06, 2006, 01:13:53 PM »

You said you went to new thicker radiators and a smaller pulley. Was this an upgrade to 8V92 sized radiators or something more?  If you were upgrading from a 8V71 or 6V92 system,  did you go to the larger squirrel cage fans?

Offline RJ

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Re: MCI 7 extra radiators
« Reply #18 on: August 06, 2006, 02:46:13 PM »
Marc -  In Ed's response to my list of questions, he answered "NO" to the one about the larger squirrel cage fans.

Obviously, these move more air, so are worth the investment.

Ed -  Get rid of that mudflap hanging off the back bumper - NOW!  Those things trap hot air UNDER the coach, not allowing it to escape.

GMC hung a full-width stiff mudflap across the coach immediately behind the back axle to create a low-pressure area under the powertrain, thereby helping to draw the hot air out of the engine compartment. 

These are a little more of a challenge to fabricate on a T-drive coach, but it would be worth the $$ - which I'm sure would be a lot less than adding another radiator and associated plumbing, etc.

HTH. . .
RJ Long
PD4106-2784 No More
S13406 1978 MC-5C Converted 6V71/MT-644
S14947 1980 MC-5C Shell 6V92/HT-740
Cheney WA

Offline edvanland

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Re: MCI 7 extra radiators
« Reply #19 on: August 06, 2006, 03:24:35 PM »
Meny thanks to all who have responded.  I now know a lot more of what to look for and what to do.  I think the first thing is to figure out the trans cooling better.  I will also take the bus to a Allison Trans man in Phoenix, who did a rebuild on a friend's GMC.  Will let you know latter what I have done and how it works thanks to all your efforts and ideas.
Ed Van
Cornville, AZ

Offline busnut104

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Re: MCI 7 extra radiators
« Reply #20 on: August 06, 2006, 07:58:10 PM »
In the comp. where the heater radiator and fans are located there on both sides fiberglass chutes that deliver the air to the inside of the coach. I made for each side a metal shoot which I can close off the air from going inside and directs to the outside with a metal slide, When I want heat in the coach I have a end cap that I install. YOu would not believe how much hot air with a lot of force comes out of the shoots. If you would like I may be able to post some pictures.