TR4/4A Tach and Speed inner gaskets

I have my dash apart and was cleaning the inside of the Speedo and Tach Glass. I noticed the inner glass gasket is cracked and falling apart.

Has anyone tried just a generic gasket about the same size from McMaster-Car?

I hear some gauge companies sell them at crazy prices but......

https://www.mcmaster.com/#5288t291/=12r75i1

wonder if this would work? $8 for 25, if it does I'll have some spares.

IMO something that hard is going to make it really tough to get the bezel back on. You need something that can compress under the meager force you can apply.

I found some very soft tubing that worked well for me. Sorry, I don't have the details handy.

I use a black strip caulk by 3M and roll it with my hands into an "o ring". It can be trimmed with a razor blade after installing the glass and bezel.

Maybe similar to what Brinkerhoff used, I just got some "rope caulk" at the local hardware store to replace a missing taillight seal on another car, basically a putty on a roll somewhere between 1/8" and 1/4" in diameter, it can be combined to make thicker, or rolled and stretched to make thinner. Tacky but not gooey, it would be easy to make into a compressible seal for the instruments I would think, stays soft and malleable. Wish I had tried it sooner seems like a viable option for many gasket and sealing issues where not exposed to engine heat or fluids. Only a few bucks.

I've used that 3m caulk rope on taillights. That is not something I want on the inside of my gauges. I'll keep looking for a softer gasket or try some smaller tubing like TR3 driver suggested

I got some 3mm and 4mm sponge seal from eBay, exactly the right thing for the job. Comes from UK, but very quick.
You don't want caulk!

As Randall said, you really don't want anything rigid like the backup ring at McMaster.

I have used window screen spline from the home center. There are several different sizes to pick from. Lowes and Home Depot don't always carry the same sizes and that gives you even more to pick from. The spline is tubular and compliant so it will fit between the glass and bezel.

You can also buy foam cord from various U.S. and U.K. sources. I have purchased it from Auto Electrical Spares in the U.K. A link is below but this is just for one size. I believe they have a couple of different diameters.
https://www.autoelectricalspares.co...rd-seal-x-1-meter-for-smiths-bezel-1294-p.asp

Auto Electrical Spares also sells some of the bezels and glass which might help you justify ordering from Europe.

dklawson said:

As Randall said, you really don't want anything rigid like the backup ring at McMaster.

I have used window screen spline from the home center. There are several different sizes to pick from. Lowes and Home Depot don't always carry the same sizes and that gives you even more to pick from. The spline is tubular and compliant so it will fit between the glass and bezel.

You can also buy foam cord from various U.S. and U.K. sources. I have purchased it from Auto Electrical Spares in the U.K. A link is below but this is just for one size. I believe they have a couple of different diameters.
https://www.autoelectricalspares.co...rd-seal-x-1-meter-for-smiths-bezel-1294-p.asp

Auto Electrical Spares also sells some of the bezels and glass which might help you justify ordering from Europe.

Click to expand...

That's who I used. Good shop!

found it,

Looks like it's made for this

https://www.ebay.com/itm/NEW-3mm-Sp...ash=item463c812020:g:kIUAAOxyQj9RLTP6&vxp=mtr

That looks like it...a very soft foam that you cut to length. Better price than nisongers too!

Zitch said:

found it, Looks like it's made for this

https://www.ebay.com/itm/NEW-3mm-Sp...ash=item463c812020:g:kIUAAOxyQj9RLTP6&vxp=mtr

Click to expand...

It is. That eBay link is to the eBay store for Auto Electrical Spares... the company I mentioned and provided links to.

As I wrote above, they also sell a 4mm size, which fits better on larger instruments.

However there are 2 gaskets on the glass. One toward the bezel and one toward the metal inner ring that looks like a paper gasket.

The gasket that was in the V of the chrome bezel has crumbled away and looked to be a caulk of some type. The other inner paper gasket is intact.



OK I see you can where you can use the caulk now or the 4mm foam.

But that inner paper gasket between the inner bezel and the glass is that available or does one have to cut out of paper gasket?

I made the rings from heavy construction paper and a circle cutter.

I echo the advice for Auto Electrical. I just ordered the flat o-rings that go between gauge and panel, as well as some foam cord to go between bezel and glass. (Note, the o-ring from Moss actually works decently well between bezel and glass for the speedo and tach, but does require some "futzing" to get it in place, as the or-ring diameter is a little too small.) The Moss o-rings are supposed to go between gauge and dashboard, but I found them to be quite thick, and make the gauge stand proud. I'll see how the Auto Electrical parts compare, and will report back.

I also ordered two of the "shovel" clamps to hold on the speedo and tach that were missing when I disassembled the dash. Expensive - $15 each, plus shipping! (Sourced from Anglo Parts, https://www.angloparts.com - no financial interest, etc.) I could not find these supplied anywhere else, except on ebay, at similar prices.