"Marvin Wood Double Hung Windows - How to Replace a Broken Sash Tube"

 By Ron Stultz

9 Dec 2013

Summary: key is to remove vinyl track from wood frame and then any repair is do-it-yourself (DIY) "easy".

Background:

If a window is difficult to lift open, you might have a broken sash tube.

If when you lift a window up, you see a string or elastic dangling like shown below, you definitely have a broken sash tube.

You can order sash tubes from Marvin but will have to know the exact length, which is marked on the lower end of the tube and can be read with the sash tube still installed in the vinyl track.

Marvin will also do house call repairs if after reading this you do not want to attempt DIY.

Definitions:

In image above can see window, wood frame, vinyl track and sash tube (grey metal).

For definition, the "sash" is the part of the window that contains a spring and a latch/catch such that the window will go up easily, helped by the spring, and stay in place where ever you want it to stay.

Image above shows 2 sash tubes.

Tubes come in various lengths.

The tubes above are 28 and 30 inches.

Notice that these tubes are both for inner window because of long metal clip at upper end.

Tube for outer window has a much shorter clip.

Image above shows lower portion of sash tube with latch or catch (blue).

Image above shows upper end of sash tube.

Above image shows sash tube catch or latch (removed from defective tube to show detail).

Above shows groove in latch or catch that must be fitted into vinyl track.

Sash failures:

Really, there are only 2 types of sash failures:

In image above, the metal "pulley" that clips on to the bottom of the spring broke.

In image above, metal rivet that holds clip that goes over vinyl track edge broke away.

DIY tools needed:

Needle nose pliers.

Flat blade screwdriver.

Replace broken sash tube:

Remove the both windows from vinyl track. "Marvin Wood Double Hung Windows - How to Till In for Cleaning or Removal"

Remove vinyl track from wood frame. "Marvin Wood Double Hung Windows - How To Remove Vinyl Track"

To remove broken sash tube, slide tube up enough to get hook off upper vinyl edge, if it is even still hooked at the top.

Use a flat blade screw driver to move the metal tube in either direction until it is completely out of the vinyl track.

If your vinyl track is broken out at the top where the sash tube clip goes, you are going to have to repair the vinyl track before installing a new sash tube.

The image below shows a vinyl track where the sash tube clip has broken the vinyl.

Take new sash tube with clip installed at upper end and slide it into channel in vinyl track.

Once you get close to having the entire tube in the vinyl channel, you will have to use pliers or other to properly align the plastic catch into the channel.

I do not have a perfect image of how the catch must sit in vinyl channel but there is a ridge on one side of the channel and an opening in the catch, which must align.

Look at vinyl channel opening, on edge, and you will see ridge.

Look at catch and you will see where ridge in channel must fit in catch.

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Getting the catch properly aligned in the channel takes some doing as you have to hold the tube tight and pull the catch down against the resistance of the spring.

Once you have the catch properly in the channel, you might have to use a flat blade screw driver to get the teeth to unlatch from the side of the vinyl channel. The catch teeth are spring loaded so push down on where the teeth pivot on the catch and the teeth should release.

With the catch teeth released from the side of the vinyl track, slide the sash tube all the way up the vinyl channel until the clip at the top of the tube can be slipped over the vinyl track.

The image above shows the sash tube clip firmly over the center of vinyl sash tube channel at the top.

Now you will need to slide the catch downward enough to allow reinstallation of the window once the vinyl track is back into the window frame.

Take a flat blade screwdriver and insert into where catch is in vinyl channel and pull downward 6 inches or more and then slowly release screw driver.

The teeth of the catch should dig into the vinyl track and stay in position.