Heater & Air Vent Controls

[tucsonwis]

We have a Maule MXT-7-180 and the heater control knob (valve) has a tendancy to open automatically during flight (must be caused by the air pressure on the valve). It is a pain in the neck to continually close this valve. Has anyone else experienced this problem? Any suggestions on resolving it? In addition, the fresh air control knobs (valves) have a tendancy to close during flight. Strange!!!!!!!!!!!!!!!!!! Looking to improve our temperature comfort in the bird. Any help would be appreciated.

[Maule 9V]

If the M-7 is made like my M-5 then the friction of the metal slide or valve is the only part of the system that will hold the adjustment where you put it. In my plane the problem is one of keeping it clean and lubricated so it works smoothly. But perhaps the slide portion can be tightened slightly by gently crimping the edges of the slide with pliers (very slightly). I have never tired this.

[maules.com]

The shaft attached to the knob has a groove in it.
The ferrule in the panel which the shaft slides in has a tongue which locates in the groove.
To prevent creep in or out the ferule should be turned in the panel and re-tightened so that it binds with the shaft.
To operate the control the operater must first turn the knob slightly to align the groove freely from the tongue, then position where it is wanted and release the twist action. It will then stay in place.

[Maule 9V]

Thanks, Jeremy. It's always good to learn from you.

[Hottshot]

Thanks, Jeremy. It's always good to learn from you.

.


I second that one!!

[maules.com]

Oily side down, Bug side to the front.

[tucsonwis]

Thanks for the quick responses to my heater control issue. I will try the recommendations.

[Lowflybye]

While your at it...disable the parking brake cable cable at the master cylinder attach point. You will never use it and it could possibly save you from a propstrike...trust me.

[maules.com]

Lowflyby, re the brakes. If they are adjusted properly, they will not lock however many are not set correctly. In my post at Bcp it is very important to check the brakes TWICE in a row before landing. Only the 2nd brake press can tell you if there is a lockup, in which case pilot or copilot can attempt to release it Before landing. If it is broken or unreleasable for some reason the Maule can be landed on grass or dirt (alongside the runway, or divert to a better place) with locked brakes and NO noseover and kept straight. The wheels will slide as long as full up elevater is applied and judicious amounts of air are blown over the elevator from the prop at touchdown. Flaps should be raised at first wheel touch of course.
Lack of proper maintainance and inspections can allow the maladjustment to happen, but the pilot has no reason not to know about it prior to landing.

[a64pilot]

While your at it...disable the parking brake cable cable at the master cylinder attach point. You will never use it and it could possibly save you from a propstrike...trust me.

I think the only thing that could be done would be to remove the tabs from the cylinders themselves. Doing either puts you not in complience with the type certificate data sheet wouldn't it?

[tucsonwis]

Howdy...................

After trying different "fixes" for my heater/fresh air control issue, I called the Maule factory and they made the following suggestion; Place a set of plyers around the control cable about a foot behind the instrument panel and put a slight "kink" into it. The "kink" should be placed in the cable with the control pulled all the way out. I performed this procedure on the 4 cables that control the cabin heat and fresh air and the "friction" on the cable increased enough to hold the controls in place during flight. Thanks for all of the replies.