Solving a problem with the RV8 heater control cable
John Hornabrook (Woodcote Green 1781) from Queensland in
Australia has sent in this useful note on a difficulty which a number
of members downunder have faced with their RV8s. John had the help
of his chum, Greg Tunstall, who describes how the problem was fixed.
problem was an inoperative heater control. The knob turned but did
not turn on the hot water valve in the engine bay. You could see the
cable trying to push the tap but it would not operate the valve properly.
With the cable disconnected (at the tap), the tap could be operated
manually without much effort but the cable was not doing its job.
We had made a decision to fit a remote cable and a suitable tap to
overcome the problem. But after investigating the lack of accessibility
to do this and the availability of the parts, we decided to try and
fix the existing set up.
First we needed
to get access to the control in the dash to see if it could be repaired
or replaced. After stripping out some of the centre console and dismantling
the dash and woodwork around the controls, we were left with a large
plastic control box that has three controls on it. The far right hand
was the heater. We could see the cable from the heater tap entering
a groove in the box. The cable outer had come out and was just moving
along the wire inner every time you moved the control knob. Closer
examination proved that this was the only problem with the box and
it seemed that re-securing the cable
would cure the problem.
The cable was supposed to be secured to the box with a plastic U shaped
clip. We prized it off with a screwdriver, relocated the cable and
attached the clip.
This seemed to do the job perfectly but we were concerned that it
might push the cable off again after refitting it. The best way to
secure it was to undo the clip and put some polyurethane glue/sealer
on the cable at the clip and reattach the clip. Polyurethane is really
rubbery and strong w hen it sets so it should bond it in place securely.
We did all this without removing the box from the dash, just manoeuvring
it to gain access where needed. This is a bit fiddly but works well.
We then screwed the box in place in the dash and went into the engine
bay to the heater tap assembly. Minor adjustment here to the outer
cable clamp had the tap working perfectly.
We would have
liked to remove the cable completely to lubricate it but it would
have been almost impossible because the end of the inner wire is bent
in loops to attach to the tap. I am not sure at the box end because
it is internal and you cannot see it unless you dismantle it ( if
you can ). The last thing to do was to refit the woodwork and console
section etc. This proved to be very fiddly, just getting the woodwork
straight seemed impossible but it all came together well.With
the job completed the last minute test proved it worked well, maybe
a little stiff but not difficult to use and we did not have to buy
a new control box or fit a remote tap and cable.
reserved by the V8 Register