Possible solution to slow windows?

[dnb]

My Griff has been suffering from slow windows for a while now. I thought this was perfectly normal until the driver's side finally gave up and stopped working entirely.

It turned out that the glass had jumped out of the back channel due to the felt insert sliding out.
I found that when I put everything back together the window seemed to be jamming on something, so I removed everything from the door so I could assemble it on the bench.

I then discovered that the front channel was completely the wrong shape for the glass! It wasn't distorted in any particular place - instead it was simply far too curved for the glass, so it loaded the mechanism almost to the point of jamming when the window was around half way down.

I have high hopes I will have a speedy window when I get the door back together on Friday.

[Barreti]

How have you altered the shape of the front channel then dnb? Its a thick lump of metal to be bending and isn't it supposed to line up and seal against the windscreen?

[450Nick]

I'd be intrigued to hear what you do as I've got the same problem.

So far, I've pulled off both door cards, removed both bits of window glass and lubed EVERYTHING. I've opened up the motors and sprayed a bit of lube in there, sprayed contact cleaner on all connections and reconnected everything (checking for good voltage in all the major bits), replaced the seals at the bottom of the window glass and checked all window runners for anything loose. I then did the windows back up tight on their mounts and I noticed a cause of the problem...

The cradle that holds the bottom of the window has worn so that there is some slight rotational play as it sits on its guides. This allows the window glass to twist back and forth along a plane slightly and cannot be eliminated by tighening any bolts. It looks the the mechanism is either worn or was crap in the first place. The effect of this is that when the motor tries to push the window up, it tilts very slightly and drags both corners on the front and rear channel felts. Pushing the top back corner of the glass down (or pulling the top front corner up) during operation just about doubles the speed of the window, even though you are not actually assisting the motor. So really that mechanism just needs to be tighter in my case. I'm sure the curvature of the channels is too much as well though. I don't really want to replace the entire mechanism though as it isn't cheap, and I'd need to do both!

[Reeso]

I think most owners have this problem. I use silicon spray on the channels. This does make things a lot better as it allows the glass to move with less friction. Still not great, but miles better!

[steve-V8s]

The mechanical arrangement may be less than ideal but another factor is the thin wires TVR used. Try measuring the voltage across the battery and the voltage across the motor on mine there is a fair of volt drop somewhere.

[450Nick]

steve-V8s said:

The mechanical arrangement may be less than ideal but another factor is the thin wires TVR used. Try measuring the voltage across the battery and the voltage across the motor on mine there is a fair of volt drop somewhere.

Yeah tried that, I have a good 12v across the motor, so its getting plenty of power. I've heard of people having this problem though hence why I used lots of contact cleaner to be sure.

[clive f]

have been working on the same problem, completely stripped the doors out and found that the front channel curve is okay, and yes this lines the glass up with the seal behind the windscreen pillar, however the rear channel is formed in too tight a radius, after much bashing with a mallet between 2 blocks of wood it did improve things, but I wonder if the motors aren`t up to the job, plus the fact that the runners need to be a very accurately aligned, but more importantly rigidly mounted, something that is not really achievable in a fibreglass door that flexes al over the place.

if you remove the rubber seals the windows flys up and down at warp factor 10, with the seals in just sit and wait

basically a st design that we have to live with.

[JonathanT]

out of interest, how are the front metal channels fixed to the door. My driver's side is a bit wobbly and gets sucked out at speed leaving me with a horrible wistle in the resulting gap. Maybe I need to jam it tighter into the roof?

[spend]

clive f said:

if you remove the rubber seals the windows flys up and down at warp factor 10, with the seals in just sit and wait

basically a st design that we have to live with.

Sounds like you answered your own question to me, ie degradation of the seals. Find new seals that are flexible with little resistance?

[Bluebottle]

I seem to remember Modwise doing a write up on this issue a while back, said that the issue was that whilst 12v was getting to the motors, the wires were too thin for the motor to draw enough current?

[clive f]

spend said:

clive f said:

if you remove the rubber seals the windows flys up and down at warp factor 10, with the seals in just sit and wait

basically a st design that we have to live with.

Sounds like you answered your own question to me, ie degradation of the seals. Find new seals that are flexible with little resistance?

hi Dave, the reason for the strip down was to fit new seals in the first place, the outer one to stop the water running down into the door,its been driving me nuts, they now open and close and seal where they should, but having a look at thicker wiring may be a good idea.

[dnb]

Mine has had the wiring upgraded. Naturally this did not solve the mechanical problem and I still had slow windows.

The back channel on my car was the correct shape.

I am now wondering if it is the glass shape that is different on everyone's car or the channels that are different...

I also wonder if a couple of "interestingly shaped" strips of metal could be made such that they would hold the two channels in position relative to each other. As an assmbly, the window could then be aligned to the rest of the car.

[spend]

clive f said:

spend said:

clive f said:

if you remove the rubber seals the windows flys up and down at warp factor 10, with the seals in just sit and wait

basically a st design that we have to live with.

Sounds like you answered your own question to me, ie degradation of the seals. Find new seals that are flexible with little resistance?

hi Dave, the reason for the strip down was to fit new seals in the first place, the outer one to stop the water running down into the door,its been driving me nuts, they now open and close and seal where they should, but having a look at thicker wiring may be a good idea.

I was suggesting trying to improve the runner seals, something that has less stiction. I think that has been well proved as 'the fix' over the years by continual liberal application of silicone spray?

The curvature is a bit misleading IMHO, it just makes the glass vertical when parked and angled slightly when closed. So the glass is mainly held at top & bottom in the runners IYSWIM. That in itself puts greater material requirements on the runner seal material over one that is straight? There must be some modern cars with pillarless windows designed to angle in against the seal at the roof which may use a better runner material?

[dnb]

The Subaru Impreza has pillarless windows.

The runners in its doors conform to the shape of the glass properly, so it works!

[spend]

dnb said:

The Subaru Impreza has pillarless windows.

The runners in its doors conform to the shape of the glass properly, so it works!

So 2 edges of the glass are unsupported when the door is opened? I've not seen a Subaru like that, but then again I don't tend to give them a second look (normally too busy pissing myself at the silly exhausts)

[dnb]

Yes - both edges are unsupported when the door is open.

Mine has equal length manifolds so doesn't make a silly noise any more

[Full Throttle]

http://www.electricwindowsdirect.co.uk/contact/

Best price for new TVR Griff window mechs by far, just thought i'd let you guys know!

[LordGrover]

dnb said:

Mine has had the wiring upgraded. Naturally this did not solve the mechanical problem and I still had slow windows.

The back channel on my car was the correct shape.

I am now wondering if it is the glass shape that is different on everyone's car or the channels that are different...

I also wonder if a couple of "interestingly shaped" strips of metal could be made such that they would hold the two channels in position relative to each other. As an assmbly, the window could then be aligned to the rest of the car.

Do you have a dimensioned sketch dnb?
There's all manner of extrusions available off the shelf that may do the job?

[dnb]

Not got as far as dimensions yet - need to test it out inside a door first.
I will most likely involve you in the very near future Grover

[SonicHedgeHog]

I've got the modwise kit. Fastest windows in the west.