Problem with flaps in heater box

Jim in france

New member
Hi everyone,

I joined the forum in the hope of getting some advice on a problem I have with my motorhome which is left hand drive based on Sprinter 313cdi. Year of vehicle 2001 but its only done 36,000 miles.

The selector on the dash to adjust where the blown air comes out was very stiff and it got to a point where I couldn't move it. I have removed the heater control panel and lubricated the moving parts but this did not help. I disconnected the cable which operates the yellow cam on the back of the heater box and found I could then move the heater control 360 degrees. The yellow cam on the rear of the heater box is very stiff to move so its the cam of the flaps within the box which are the problem!!

I have read here that it is a big bad job to change the heater box and perhaps beyond my capability.

Is there anyway I can get to the inside of the heater box to try and fix this?? The heater is working just fine so there is no need to replace the matrix. When I move the yellow cam (with a lot of effort) then the blown air comes out on the windscreen or my feet so the flaps are doing their job. Its just so very stiff that the cable cannot cope with it. I have lubricated the yellow cam from the outside but this has made no difference. I have removed the bottom of the heater box in the engine bay but cannot get my hand into it far enough to be able to feel what is going on or to spray some lubricant into it. I have left the cam disconnected for now with it selected to heat my feet but I would prefer to fix it properly so I have all the options available. ie feet/screen and all the choices in-between. Any help or advice would be most welcome. Thanks Jim
 
Last edited:

ECU

2006 T1n 118 Sprinter
The entire heater box is one part. I've never tried to get into it. I've not read of any problems like yours. Could it be dirt inside?
There is a filter box under the hood and maybe you can reach in through that a bit. It is up at the top.
There is a service manual I found for the 2006 in the manuals section that could give you some clues.
 

Jim in france

New member
The entire heater box is one part. I've never tried to get into it. I've not read of any problems like yours. Could it be dirt inside?
There is a filter box under the hood and maybe you can reach in through that a bit. It is up at the top.
There is a service manual I found for the 2006 in the manuals section that could give you some clues.
Thanks ECU, I tried reaching in through the filter box but need the hands the size of a 2 year old child to get in there:) I have the 2006 manual but cannot find any information on the flaps which control the floor vents. Someone posted some great pics of how the top flaps work but I cannot find anything about the bottom flaps. They must be stuck in the closed position as there is nothing coming out of the floor vents. I am not keen on stripping out the cab but if I could gain access by cutting a hole in the box situated under the bonnet I would gladly do this. Mr Google doesnt help, cannot find any info on there:-( Anybody got some decent pics?? PS......I dont have air-con on my vehicle.
 

ECU

2006 T1n 118 Sprinter
When set to split up/down you still can feel quite a bit of air coming out the vents.
Even at best, the air prefers to exit the dash vents and top vents. Manually shut them all to push the air either to defrost or floor.
 

220629

Well-known member
I agree that accessing the assembly would be more effort than I would be willing to do.
... I have lubricated the yellow cam from the outside but this has made no difference. I have removed the bottom of the heater box in the engine bay but cannot get my hand into it far enough to be able to feel what is going on or to spray some lubricant into it. ...
Were I in your situation I would use a step drill to drill a hole in the plastic case. A properly located hole should allow you to use the WD40 red straw to spritz lubricant into the flap area. WD40 or an equal will add some smell for a time, but the smell should dissipate in a short time. The lubrication hole can be resealed using tape or putty.

vic
 

Top Bottom