Underdash air leak

[HoosierDaddy]

There are (2) 3/16" "vacuum" hoses coming through the floor near the steering column. One appears to go to a 6" sphere shaped plastic tank just ahead of the accelerator pedal mounted on the front wall. The other is not hooked to anything...it just blows air pressure. Can anybody tell me what it is supposed to hook to??

Thanks,

Dean

[fulltiming]

Dean, I will check on the hose location during the next day or two but that is the vacuum sphere for changing the heater/defroster setting.

[HoosierDaddy]

The temp got up to 45 degrees today!!! I tried to do a little more investigating into the leaking air hose. It doesn't leak unless the coach is aired up AND the ignition switch is to the "on" position. Turn the switch off and leak stops immediately.


Still perplexed!!!
Dean

[fulltiming]

Dean, I did one short investigation under the dash. I found the vacuum sphere and the hoses but you really have to be a contortionist to get back in there to trace the air hoses.

I have been distracted lately by my new grandson BUT within the next 10 days I will be doing some SERIOUS investigation under the dash. I have been traveling in cold weather and would be freezing to death unless I run the generator and the electric heaters. My front propane heater igniting quit a couple of weeks ago so that is no help and my dash blowers blow very little air at idle and virtually none at 70 mph.

I may have multiple problems. I don't think the deflector valve is working since I have air coming out the dash vents in Air, Vent, Heat and Defrost modes. I hear the blowers speed up as I switch the fan from low to medium to high but the air flow is pitiful. I also find that the air intake under the co-pilots seat lets in ton's of cold air when the coach is parked in cold weather. I also suspect that the supplemental water pump in the engine compartment on the drivers side is not working and thus not boosting the flow of water the 40+ feet to the front heater. When I idle, some warm air comes out the dash vents. At 70 mph virtually no air, warm or otherwise comes out.

The long and short is I will be taking a serious look at the workings (or non-workings in my case) of the front chassis heater system shortly and post what I find. I will also find where those air lines go from the vacuum sphere.

Dean, since you leak only occurs when the coach is aired up and the ignition switch is on, you have a leak in a system that is solenoid controlled.

[2dogs]

FullTiming: At least your fans work. On our '87 the recirculating pump is located behind the front bumper on the passenger side. On ours the cold air when parked is because of 2 holes under the heater (just forward of the passenger side front tire). The pump in the driver's side bay is for the bay heater. Behind the heater control on the dash there are several small vacuum lines that control the vent defrost/heat. For your propane heater, ours won't ignite either and we are working on that one ourselves! Try the sail switch. I have the owners manual if you need a copy. And as for Dean's air leak, I would guess at the wipers. See if they work. The connection is above the ball.

[fulltiming]

I had assumed that Dean's wipers were electric since mine are but that would be good thing to verify. I do have a manual for the furnace but I really appreciate the offer.

I will start another thread for my heater issues to avoid highjacking Dean's thread but I will see if I find similar holes near my heater.

Dean, how many hoses do you have coming out of your vacuum sphere? I have one larger hose and a second very short hose that goes to a white plastic T that connects to two slightly smaller hoses. I have 'presumed' that the hose with the T is the vacuum side but I have not verified that yet.

[larryweikart]

Getting in on this in the middle but maybe I can help confuse tne issue. I had similar problems with adequate heating during cold weather. First, my dash air/heat was stuck on defrost and I found the plenum (located in the generator aux fan comp directly below the passenger seat) was stuck (rusty) and, of course, no parts readily available so I had it changed to be stuck on dash air/heat, as I have mounted aux fans on the windshield and would prefer the air/heat coming out of the dash onto me. I also had an issue with too much cold air entering the coach thru the dash area and have pluged all of those with rags. (helped considerably) The biggest leak was discovered inside the fuse panel in front of the passenger seat. My rear propane furnace will not light either so if you find out the fix, I would appreciate knowing. Hope some of this helps. I have a question for fulltiming and hoosier daddy. Do you change your own air filter and, if so, do you have any shortcuts? It takes me forever!

[fulltiming]

Larry, when you asked about the air filter, are you referring to the engine air cleaner? If so, it is somewhat of a bugger to get in and out. There is a clamp at the rear (toward the engine) that has to be removed and two clamps around the filter itself. It took two mechanics at Detroit Diesel to get it off and back on again and then they rotated it 90 degrees from where Newell had it (opening toward the front instead of opening toward the ground) so I am not sure which is right.

Basement A/C Filters
If you are referring to the air filters for the basement airs, I also find that is a big job due to lack of access. Since each coach is different, I am not sure how much using mine as an example will help, but for what it is worth, the easiest is the one in the bedroom where the grill comes off and you can reach right in and change the filter. The worst one is the one under the kitchen sink which requires removing a couple of shelves in the kitchen cabinet under the sink and removing the interior panel that separates the cabinet from the A/C chamber. The one under the coach can be accessed by lifting the coach but it is a very long reach. The one under the refrigerator requires removing the panel on the outside of the coach and going in from the outside.

Dash Heater/AC damper
I will attempt to find the damper. I have had that plenum open before but don't remember seeing the damper. I know that cold air comes back in through the intake vent under the passengers seat when it cold outside and the coach is parked. My heater blowers do put out a little air when stopped through the dash vents but there is an obvious obstruction somewhere. I don't get any air going to the defrosters when I put the AC/Heater control in defrost so I guess my damper is not moving.

Rear Propane Furnace
On your rear propane furnace, if it is like mine (bottom of the closet in the bedroom) access is easy (unfortunately it is the front furnace on mine and access is not good at all). If the fan starts when you lower the thermostat, the three most likely causes of the heater not lighting are 1) sail switch, 2) control board, 3) igniter. In may case, I may have a fan issue and it just isn't turning fast enough to activate the sail switch since it start squalling like crazy but worked, then quit squalling and hasn't lit since.

[larryweikart]

Thanks for the reply Michael. Sorry, I was referring to the air cleaner and it is impossible for me to exchange mine without total removal of both turbo pipes which is a real chore. Thank heavens it is only necessary every 50,000. Thanks for the good advice on the rear furnace, I'll be looking into those items. As for the a/c filters, they have placed all 4 of mine inside in easy to get to locations. Each year they improve. Happy New Year and Happy traveling. Larryjavascript:emoticon(':roll:')

[fulltiming]

Interesting. Do you have the Series 60? My 8V92 has the air filter mounted on the passengers side of the engine where access isn't too bad, just a very close fit. When Newell went to the side radiator with the Series 60, the placement of a lot of things changed.

[larryweikart]

Sorry, I should have thought of that. It's a series 60. Explains a lot of things.