I read several posts about how to improve window performance.

I’m now convinced that if you have replaced the window felts, you will not be happy with the windows speed afterward.

I have replaced the felts twice with the product sold by major parts seller. If I installed the 1-piece design as it comes, then the window will not seat because the top felt is too tight because the frame appears slightly smaller than the sides.

I ended up buying universal felts and mixing and matching and now my felts are 3 pieces per window. I was eventually able to get the windows to move “okay” but not great.

so I came to the forums and read the fixes about cleaning connectors, cleaning switches, lubing linkages etc. after cleaning all the switch contacts and connections in between, and lubing the pivots on linkage, AND enlarging the holes where the window motor/regulator mounts so that I could change the orientation slightly. I had slightly better windows.

So I went back and measured voltages and saw I was still losing voltage across my (cleaned ) switches. So I bought a new old stock switch and it also had a voltage drop. Ugh.

then I stumbled across a Jeep CJ forum where they also struggle with slow windows. AND a Ferrari forum where they struggle with slow windows. And in each forum I discovered a discussion about voltage converters, ie, stepping up the voltage.

I did notice that my windows worked better with engine running and so decided to give it a shot. They have a million varieties, I purchased one that steps up to 13.8v and installed it. It worked pretty good. But I realized that I was still losing voltage across the switch and so I was only getting 12.5/6v going to window. And this was with 13.8 coming in. And so i bought a converter that steps up to 15 v, which means it’s sending a little over 14 to motor, which I’m pretty sure is within limits since alternators can go to 14.7.

install was super easy, I removed the master cut out switch and extended those 2 wires under the console and seat and mounted the converter on the seat mount. Before it took 6 seconds to raise the right rear window (and it wouldn’t fully seat) and now it closes completely and takes 4 seconds to close.

pics

 

Andy
Great fix, do you have a link to the gizmos please! Going forward, silicone spray regularly on the felts helps too.

 

here is the one I bought. and good tip on silicone, i used one of those dry lube products but gonna also try silicone

 

Many thanks, Andy. I had never heard of such things before!

 

in the XJ-6 everything is slow with engine off.
Ask me about the Wipers !

 

Though it's not always convenient, a relay, mechanical or solid state, can be a good way of avoiding the effects of voltage drop at a switch, wiring, and connections.

 

As Jose' said the windshield wipers are slow. Wonder whether it would work on them?

 

I think it is the motor itself. It is the lame slow motor fitted to all XJ-6 Series 1, 2, and 3 cars.

Compare with the wiper motor in my '65 S type, the Lucas DR3, is way faster, but it doesn't have the third, intermittent speed of the XJ-6 motor.

but the Lucas DR3 motor has an adjustment knob that lets you fine tune where you want the wipers to Park exactly.

Both motors connect to the cable almost identically.