Troubles Installing 914 Rear Windpw

[RSOHC]

I am having trouble installing the rear glass of a 914 so that it does not leak.
I am using 8 mm (5/16 inch) butyl on a paper roll.
I have followed the guidelines published by Automobile Atlanta.
Any tips on installing the rear glass would be appreciated.

Lauran

[Dave at Pelican Parts]

What troubles are you having?

I removed all of the trim around the window, plus the back pad. I don't know how much of that was strictly necessary, but it made access much less annoying. I left the seats in, and grabbed some beach towels that I rolled up.

Cleaning the old sealant out of the channel was the most annoying part of the exercise.

I heated up the rear window (left it in the sun for a while) to make sure the butyl would stick well. I used gloves to keep my skin oils from getting on stuff.

The butyl on a roll was easy, you could use the paper to press the other side of the stuff into the channel. I wasn't sure it was sticky enough, so I used a hair dryer to warm it up a bit. I stuck the two spacers in the bottom after that.

Then I slid the window into place, and slid the seats back as far as they would go, with the rolled-up towels between the headrest and the window. This held the window in place reasonably well near the bottom. I used a block of wood and a large clamp to hold the top of the window, to make sure there was decent contact with the sealant there.

--DD

[RSOHC]

Dave,

Did you warm up the butyl before or after it was attached to the car body?
Is the butyl installed as one piece?
What kind of clamp did you use?
What are the dimensions of the piece of wood?
Did you use any primer on the glass or the body of the car?

[RSOHC]

Dave,
Is the top taken off to install the clamp?

[RSOHC]

My problem is that in some locations on the bottom of the glass the butyl did not stick to the glass.

[Dave at Pelican Parts]

I installed the butyl as one piece.

The clamp was a bar clamp that I had. The piece of wood was something I had in the garage, probably a 2x4 that was a couple of feet long. The clamp went over the Targa bar, so yes the roof was off--which gave me more room to work on things.

I think I warmed up the butyl both before sticking it to the channel in the body, and after.

If yours isn't sticking at the bottom, try using a hair dryer on the glass in that area. There's a decent chance that will soften it to the point it will stick. Make sure there is contact between the glass and the butyl as well.

--DD

[RSOHC]

what is the size of the butyl. 1/4 inch, 5/16 inch or 3/8 inch?
Please describe the dimensions of the bar clamp and the brand of the clamp if possible.
Will a Jorgensen Bar Clamp with a 3 inch throat depth and a 12 inch opening work?

[dr914]

make sure the window fits the hole squarely. We have seen some that have had the roll bar tweeked in the past and the glass does not fit, and we have also seen some with a deflected firewall so that the glass does not fit

[Dave at Pelican Parts]

I do not have access to the clamp at the present time. It was "big enough" that I could hook it over the Targa bar and use wood to spread out the loads. If you have several chunks of 2x4 sitting around, you should be able to come up with something.

I think the butyl used was 5/16" width.

I don't remember the details that well now, it was quite a few years ago.

--DD

[Tobra]

There were two littl rubber bits on my rear window on the bottom edge, lifted window off the metal a few mm

[RSOHC]

From the inside of the cabin, from the top of the firewall there is a ridge, a valley, and then a ridge.
For my first effort, I put the butyl in the valley.
I think that maybe I should have put the butyl on the first ridge from the top.
Where should the butyl be placed?
Lauran

[RSOHC]

Tobra,

I found one rubber auto glass height setting block in place when I originally removed the rear window. It is 2.354" long, 0.270 " tall, and 0.131" thick. There is no groove in the block. I though that the purpose of the block was to hold the glass in position so that it did not side downward under the force of gravity.

Lauran

[RSOHC]

I have removed the seats, lateral pad and two vertical pads of the roll bar bolster, sprayed on paint primer and color in the working area, cleaned the glass, applied glass primer to the contact areas on the glass and body of the car, placed two glass height setting blocks to support the bottom of the glass. I need some direction on where to place the butyl on the lower portion of the car body before I start installing the glass.

Lauran

[RSOHC]

George from Automobile Atlanta has told me to place the butyl in the valley.

[Dave at Pelican Parts]

I placed it in the valley as well.

--DD

[RSOHC]

914 rear glass installation procedure
(1) do installation on a warm day with gloves and a razor blade
install work lights for good visibility
(2) fit wood blocks and clamps to hold top of window with towels on roll bar
(3) fit glass to car and glue in place glass setting blocks
(4) clean both sides of glass
(5) clean edge of glass with reducer
(6) install suction cups dipped in water on glass
(7) clean area on car with grease reducer
(8) warm primer with heat gun
(9) warm car area with heat gun
(10) install primer on car
(11) install primer to glass using finger as guide
(12) warm butyl with heat gun and install butyl in valley of car starting on top
(13) warm edge of glass with heat gun and install glass in car
(14) warm glass area in contact with butyl
(15) push on glass with hands to set butyl to glass
(16) install clamps to hold glass in place
(17) install seats with beach towels to hold glass in place

[RSOHC]

glass setting blocks are from 914rubber

[RSOHC]

My second effort to install the rear window without water leaks failed. Here are the steps I followed.

(1) I pre-fit the glass in the car and did not see any deviation in the firewall that would impact the installation of the glass in the car.
(2) Two glass setting blocks were glued to the car to hold in place the bottom of the glass after the glass installation.
(3) I cleaned the contact area with reducer but did not clean the contact area with hot water and a little dish washing soap before installing glass primer to the contact area of the glass.
(4) I cleaned the contact area on the car with wax and grease remover and applied glass primer. Painters green tape and paper was used to protect the area outside the area to be primed.
(5) The above work was done the day before the glass was installed.
(6) The roll of butyl was placed between two heating pads and the temperature was set to 135 degrees F.
(7) The glass was installed when the outside temperature was 75 degrees F.
(8) The glass was placed on the top of a rubber garbage can which was placed in the sun.
(9) I cleaned the contact perimeter of the car with wax and grease remover and placed the 5/16 inch butyl around the contact perimeter on the car starting at the top. I believe that I should have washed the contact area of the car with hot water and a small amount of dish washing soap before installing the butyl. The butyl was installed in the valley on the car along the bottom contact area.
(10) The glass was installed by two people with the aide of two suction cups.
(11) I pressed on the glass with the palm of my hand in an effort in increase the contact between the glass and the perimeter of the car.
(12) The next day I water tested the installation and there were many leaks along the bottom portion of the glass.

I am now in the process of removing the glass and butyl so that I can try again.
I am thinking about using 3/8 inch butyl on my next installation effort.
I believe that I need to wash any areas where reducer is used or wax and grease remover is used before the glass is installed.

Any feed back and comments on how I should do my next installation effort are welcome.

[RSOHC]

After cleaning the glass with reducer or a glass cleaner, I will be washing the glass with hot water and a dab of dish washing soap (Dawn or Ivory soap). This will be followed by washing the glass with clean water. I will also be washing the area in the car with hot water and a dab of dish washing soap and rising with clean water.

Lauran

[RSOHC]

I am ready to try my third installation. Should I use 5/16" butyl or 3/8" butyl.

Lauran