June 25, 2018, 06:41:05 AM

Author Topic: MCI MC5 OTR heat  (Read 1780 times)

Offline trucktramp

  • Sr. Member
  • ****
  • Posts: 275
MCI MC5 OTR heat
« on: December 01, 2010, 12:54:29 AM »
My PO's conversion left two metal ducts that run along the wall on the floor.  Are these OTR heat runs or returns?  Should they be removed since they use up about 3-4 inches of space.  I have thought about leaving them and using them as a raceway for electric since the current electric is just about a rough in but if the ducts can be removed easily then out they go.
Dennis Watson
Scotts, Michigan
1966 MCI MC5A
Spicer 4 Speed Manual

Offline bevans6

  • Hero Member
  • *****
  • Posts: 5988
  • 1980 MCI MC-5C
Re: MCI MC5 OTR heat
« Reply #1 on: December 01, 2010, 05:35:33 AM »
I believe they are the hot air ducts, air is ducted along them and up to beneath the windows.  I still have mine, I still use the OTR heat, but many take them out.  They are separate from the dash heat, and you can remove the OTR heat and still  have the dash heat plumbed in.  If you take them out and drive in 40 degree or colder weather, you'll need another solution for heat, dash heat won't keep up and a bus running at 60 mph in near or below freezing temps takes a huge amount of heat input to keep comfortable.

1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Spicer 8844 4 speed Zen meditation device
Tatamagouche, Nova Scotia

Offline robertglines1

  • steam nut
  • Hero Member
  • *****
  • Posts: 4365
Re: MCI MC5 OTR heat
« Reply #2 on: December 01, 2010, 06:33:55 AM »
heat outlet only / return is in floor I believe in sides of tapered isle. At least was that way on 8 I did.even if you take the duct out you still have supply coming thru floor on each side you can use as heat source.usually (supply ) about a 4 inch by 12 inch rectangular hole.  Bob
Bob@Judy  98 XLE prevost with 3 slides --Home done---last one! SW INdiana

Offline Jriddle

  • Hero Member
  • *****
  • Posts: 713
Re: MCI MC5 OTR heat
« Reply #3 on: December 01, 2010, 08:19:54 AM »
I took mine out in my 9. I have the two heater/ac outlets or supplies in the front. They blow a lot of air but only two people to cool or heat. If you remove make sure you have a return vent in the center duct near the back. This will pull the heat or cool air to the back. This vent will also help make your return air thermostat work properly. This thermostat is located mid way in the center return duct and is used to regulate temperature. Mine is not working properly right now because I have not yet cut a vent in the center duct near the back. The heating system still works but I have questionable control of temperature.

Good luck
John Riddle
Wells NV
1984 MC9